碳基荧光材料的制备、发光机理及水相应用
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摘要
碳在自然界中有很多存在形式，包括石墨、金刚石、碳纳米管等。碳材料是一种环境友好类的材料，近年来得到人们越来越广泛的关注。宏观的碳材料通常缺少合适的带隙，因此碳材料本身很难开发成为一种理想的发光材料。我们目前所讲的荧光材料通常是指无机荧光材料，如碱土金属和稀土元素；有机荧光材料，如有机小分子发光材料、高分子发光材料及有机配合物发光材料；另外还有金属半导体纳米晶或纳米簇。通过调控碳材料的尺寸和表面化学性质，可以制备新型的碳基荧光材料。本论文中，我们从最典型的荧光碳材料碳点(石墨烯量子点、碳纳米点、聚合物点)出发，详细地开展了这类材料的合成方法学，物化性质、荧光机理及新颖应用方面的工作。从关键创新点来讲，本论文在荧光碳材料领域的贡献如下：率先进行石墨烯量子点的溶液相纳米法合成，并首次了报道细胞成像应用，率先用超快光谱的手段研究石墨烯量子点的发光机理；制备了当时量子产率最高的碳纳米点，并明确提出了分子态荧光机理；提出了非共轭聚合物点的概念，并详细研究交联增强聚合物点荧光行为。具体来讲，本论文的工作归纳为如下三个方面。
首先，从化学结构相对简单可控的石墨烯量子点为起始点，作为模型体系来理解这类材料的发光机理。用溶剂热裂解氧化石墨烯制备边缘接枝氮的水溶性石墨烯量子点。在接下来的工作中我们着重探索了石墨烯量子点的表面化学调控及发光中心归属等难题。通过柱层析的办法分离得到氧化程度梯度变化的石墨烯量子点，发光峰位从蓝光到绿光可调。通过化学接枝烷基胺或还原的方式改变绿色荧光石墨烯量子点的表面化学组成，实现发光从缺陷态(分子态)绿色荧光到本征态的蓝色荧光的转变。通过瞬态吸收等超快光谱研究，我们归属了绿色荧光石墨烯量子点有两个相对独立的分子态和一个寿命较短的本征态发光中心。由于石墨烯量子点的优良的稳定性、良好的生物相容性、较好的发光性能，我们拓展了其单光子、双光子生物成像，生物传感器和太阳能电池领域等应用。
其次，当用石墨烯量子点体系深入地理解了这类材料的发光机理之后，我们选用小分子或聚合物自下而上的办法批量制备具有荧光性质的碳材料。我们选用富含羟羧基和氨基的小分子作为碳源，通过水热的办法制备荧光碳纳米点。分别调控了不同碳化分子类型，碳化温度和时间等因素，理解化学组成对形成碳纳米点种类的影响。并通过优化条件得到了发光效率达80%的荧光碳纳米点。进一步，选用了结构不同、具有代表性的三种碳点(都具有绿色荧光发射)作为研究对象，通过瞬态光物理过程的研究，了解到连接在碳核表面的羰基、羧基或酰胺键是这类材料典型的绿色发光中心。此外，利用碳纳米点较高的荧光量子产率和较低的生物毒性，我们开发了碳纳米点荧光墨水、纳米图案化、纳米复合物、离子检测及细胞成像方面的应用。进一步地，我们选用几种具有代表性的碳纳米点，研究了尺寸、发光效率和表面电势对细胞成像的详细影响。
最后，我们进一步拓展开发了一种新颖的碳点材料——聚合物点，这类材料不但具有碳材料的荧光性能，还保持着聚合物易加工的性能，更加具有实际应用意义。我们选用具有可脱水基团的线性聚合物，如聚乙烯醇、多糖、聚乙烯亚胺等，进行适度脱水碳化或团聚制备荧光聚合物点。所制备的聚合物点具有单一发光中心，细胞毒性较低，可应用于细胞成像等领域。另外，采用沉淀组装有机合成的稠苯类石墨烯量子点的办法制备具有荧光性能的聚合物点，详细地研究了这类材料的发光行为。进一步地，我们还研究了模型体系聚乙烯亚胺中交联增强荧光行为：聚合物点中的交联可以降低发光中心的振动、转动弛豫消耗的激发态电子无辐射跃迁，从而增强荧光性质。最后我们拓展了荧光聚合物点在纳米复合物制备方面的应用：由于聚合物点不但含有荧光性质的发光中心，还有键连的化学基团，因此具有高分子易加工的特性。
总之，从石墨烯量子点理解碳材料发光机理，到碳纳米点和聚合物点的批量制备和应用，我们在本论文中遵循着理论探索和实际应用相结合的研究思路。为荧光碳材料的种类拓展、多样合成、明确发光机理及新颖水相应用方面做出了里程碑式的工作。
There are many forms of carbon existing in nature, including graphite, diamond,carbon nanotube and so on. Carbon material is a kind of environmentally friendlymaterials, which has draw incresing attention in recent years. Macroscopic carbonmaterials often lack the appropriate band gap, which are difficult to be developed asideal fluorescent materials. The fluorescent materials often contain inorganicfluorescent material, such as alkaline earth metals and rare earth elements; organicfluorescent materials, such as small organic molecules, polymer as well ascoordination compounds. Besides, the semiconductor nanocrystals or nano clustersare rising kind of fluorescent materials. By regulating the size and surface chemistry,the carbon can be developed to be a new type of fluorescent material. In this paper,we are focusing on the carbon dots (graphene quantum dots (GQDs), carbon nanodots(CNDs), polymer dots (PDs)), the most typical fluorescent carbon materials. Thesynthesis methods, physical and chemical properties, fluorescence mechanism andnovel applications on carbon dots were investigated in detail. There were severalcritical points of innovation in this paper: taked the lead in nano-solution phasesynthesis to GQDs as well as cell imaging applications, used ultrafast spectroscopy tostudy photoluminescent (PL) mechanism of GQDs for the first time; prepared the PLCNDs with the highest quantum yield and developed the molecule state PLmechanism; proposed the concept of non-conjugated polymer dots, and investigatedthe enhanced PL in crosslinking PDs. Specifically, there were three aspectsintroducing in detail in the following paragraphes.
Firstly, we take the GQDs with relatively simple chemical structure as a modelsystem to understand the PL mechanism. The solvothermally GQDs from grapheneoxide possessed edge grafted nitrogen and water solubility. In the following work, wefocused on regulating surface chemistry and figuring out the PL center of the GQDs.Using column chromatography separation, the GQDs with tunable oxidation degreeand PL emission (blue to green) were prepared. By alkyl amines grafting or reducing,the surface chemistry of the GQDs were tuned, and the defect state (molecular state)PL changed to intrinsic state PL. By ultrafast transient absorption spectroscopystudying, we attributed the green PL of the GQDs to two relatively independentmolecule states and an intrinsic state with short fluorescent life. Due to the excellentstability, good biocompatibility, outstanding PL properties of the GQDs, we exploitedtheir applications in single-photon, two-photon biological imaging, biosensors andhybrid solar cells.
Secondly, when the PL mechanism of the fluorescent carbon materials wasunderstanded in depth using the GQDs system, the bottom-up approach with small molecules or polymers was adopted to prepare carbon materials in large scale. Thesmall molecules with abundant carboxyl/hydroxyl and amino groups were used toprepare CNDs by hydrothermal routes. By regulating the types of molecules,temperature and time of carbonization, we can understand the impact of chemicalcomposition on the formation of CNDs. By optimizing the synthesis conditions, thehighly PL CNDs with quantum yield as high as80%were obtained. Furthermore,three typical CDs were chose to investigate the origin of the green PL by studing thephotophysical processes: the C=O groups (carbonyl, carboxyl or amide) connected onthe carbon core were proved to be the PL centers. In addition, due to the highquantum yield, low toxicity of CNDs, the fluorescent ink on macroscopic andmicrocosmic surface, nano-composites, ion detection and cell imaging were exploited.Further, using four representative CNDs, the size, quantum yield and the surfacepotential of CNDs were investigated how to affect the cell imaging applications.
Finally, we further developed novel kinds of CDs, named PDs. The PDspossessed both the fluorescent properties of carbon materials, and performance ofpolymers, which is significant for practical applications. The nonconjugated linearpolymers with easy dehydration groups were selected to form the PDs by moderatelycarbonizing, such as polyvinyl alcohol, polysaccharides, polyethylene imine. Theprepared PDs have single PL emission center, low cytotoxicity, which were applied incell imaging fields. Moreover, by precipitation assembling organic synthesized GQDs,the other kind of PDs were obtained. The PL mechanism was also exploited. Further,we investigated the PL behavior of crosslinked PDs system: polymer crosslinking caneffectively reduce the vibration and rotation of nonradiative relaxation consumption,thereby enhancing the fluorescence properties. At the end, the functionalnanocomposites were prepared using the fluorescent PDs: benefited from the PDs, thenanocomposites contained not only the PL emission center, but also the connectedpolymer chains.
In conclusion, from understanding PL mechanism of GQDs to producing CNDsand PDs in large scale, we followed the connection between theory and practicalapplication in this paper. The expanding the types, diverse synthesis, clear PLmechanism and novel aqueous applications of fluorescent carbon materials wereachieved in the present paper.
首先，从化学结构相对简单可控的石墨烯量子点为起始点，作为模型体系来理解这类材料的发光机理。用溶剂热裂解氧化石墨烯制备边缘接枝氮的水溶性石墨烯量子点。在接下来的工作中我们着重探索了石墨烯量子点的表面化学调控及发光中心归属等难题。通过柱层析的办法分离得到氧化程度梯度变化的石墨烯量子点，发光峰位从蓝光到绿光可调。通过化学接枝烷基胺或还原的方式改变绿色荧光石墨烯量子点的表面化学组成，实现发光从缺陷态(分子态)绿色荧光到本征态的蓝色荧光的转变。通过瞬态吸收等超快光谱研究，我们归属了绿色荧光石墨烯量子点有两个相对独立的分子态和一个寿命较短的本征态发光中心。由于石墨烯量子点的优良的稳定性、良好的生物相容性、较好的发光性能，我们拓展了其单光子、双光子生物成像，生物传感器和太阳能电池领域等应用。
其次，当用石墨烯量子点体系深入地理解了这类材料的发光机理之后，我们选用小分子或聚合物自下而上的办法批量制备具有荧光性质的碳材料。我们选用富含羟羧基和氨基的小分子作为碳源，通过水热的办法制备荧光碳纳米点。分别调控了不同碳化分子类型，碳化温度和时间等因素，理解化学组成对形成碳纳米点种类的影响。并通过优化条件得到了发光效率达80%的荧光碳纳米点。进一步，选用了结构不同、具有代表性的三种碳点(都具有绿色荧光发射)作为研究对象，通过瞬态光物理过程的研究，了解到连接在碳核表面的羰基、羧基或酰胺键是这类材料典型的绿色发光中心。此外，利用碳纳米点较高的荧光量子产率和较低的生物毒性，我们开发了碳纳米点荧光墨水、纳米图案化、纳米复合物、离子检测及细胞成像方面的应用。进一步地，我们选用几种具有代表性的碳纳米点，研究了尺寸、发光效率和表面电势对细胞成像的详细影响。
最后，我们进一步拓展开发了一种新颖的碳点材料——聚合物点，这类材料不但具有碳材料的荧光性能，还保持着聚合物易加工的性能，更加具有实际应用意义。我们选用具有可脱水基团的线性聚合物，如聚乙烯醇、多糖、聚乙烯亚胺等，进行适度脱水碳化或团聚制备荧光聚合物点。所制备的聚合物点具有单一发光中心，细胞毒性较低，可应用于细胞成像等领域。另外，采用沉淀组装有机合成的稠苯类石墨烯量子点的办法制备具有荧光性能的聚合物点，详细地研究了这类材料的发光行为。进一步地，我们还研究了模型体系聚乙烯亚胺中交联增强荧光行为：聚合物点中的交联可以降低发光中心的振动、转动弛豫消耗的激发态电子无辐射跃迁，从而增强荧光性质。最后我们拓展了荧光聚合物点在纳米复合物制备方面的应用：由于聚合物点不但含有荧光性质的发光中心，还有键连的化学基团，因此具有高分子易加工的特性。
总之，从石墨烯量子点理解碳材料发光机理，到碳纳米点和聚合物点的批量制备和应用，我们在本论文中遵循着理论探索和实际应用相结合的研究思路。为荧光碳材料的种类拓展、多样合成、明确发光机理及新颖水相应用方面做出了里程碑式的工作。
There are many forms of carbon existing in nature, including graphite, diamond,carbon nanotube and so on. Carbon material is a kind of environmentally friendlymaterials, which has draw incresing attention in recent years. Macroscopic carbonmaterials often lack the appropriate band gap, which are difficult to be developed asideal fluorescent materials. The fluorescent materials often contain inorganicfluorescent material, such as alkaline earth metals and rare earth elements; organicfluorescent materials, such as small organic molecules, polymer as well ascoordination compounds. Besides, the semiconductor nanocrystals or nano clustersare rising kind of fluorescent materials. By regulating the size and surface chemistry,the carbon can be developed to be a new type of fluorescent material. In this paper,we are focusing on the carbon dots (graphene quantum dots (GQDs), carbon nanodots(CNDs), polymer dots (PDs)), the most typical fluorescent carbon materials. Thesynthesis methods, physical and chemical properties, fluorescence mechanism andnovel applications on carbon dots were investigated in detail. There were severalcritical points of innovation in this paper: taked the lead in nano-solution phasesynthesis to GQDs as well as cell imaging applications, used ultrafast spectroscopy tostudy photoluminescent (PL) mechanism of GQDs for the first time; prepared the PLCNDs with the highest quantum yield and developed the molecule state PLmechanism; proposed the concept of non-conjugated polymer dots, and investigatedthe enhanced PL in crosslinking PDs. Specifically, there were three aspectsintroducing in detail in the following paragraphes.
Firstly, we take the GQDs with relatively simple chemical structure as a modelsystem to understand the PL mechanism. The solvothermally GQDs from grapheneoxide possessed edge grafted nitrogen and water solubility. In the following work, wefocused on regulating surface chemistry and figuring out the PL center of the GQDs.Using column chromatography separation, the GQDs with tunable oxidation degreeand PL emission (blue to green) were prepared. By alkyl amines grafting or reducing,the surface chemistry of the GQDs were tuned, and the defect state (molecular state)PL changed to intrinsic state PL. By ultrafast transient absorption spectroscopystudying, we attributed the green PL of the GQDs to two relatively independentmolecule states and an intrinsic state with short fluorescent life. Due to the excellentstability, good biocompatibility, outstanding PL properties of the GQDs, we exploitedtheir applications in single-photon, two-photon biological imaging, biosensors andhybrid solar cells.
Secondly, when the PL mechanism of the fluorescent carbon materials wasunderstanded in depth using the GQDs system, the bottom-up approach with small molecules or polymers was adopted to prepare carbon materials in large scale. Thesmall molecules with abundant carboxyl/hydroxyl and amino groups were used toprepare CNDs by hydrothermal routes. By regulating the types of molecules,temperature and time of carbonization, we can understand the impact of chemicalcomposition on the formation of CNDs. By optimizing the synthesis conditions, thehighly PL CNDs with quantum yield as high as80%were obtained. Furthermore,three typical CDs were chose to investigate the origin of the green PL by studing thephotophysical processes: the C=O groups (carbonyl, carboxyl or amide) connected onthe carbon core were proved to be the PL centers. In addition, due to the highquantum yield, low toxicity of CNDs, the fluorescent ink on macroscopic andmicrocosmic surface, nano-composites, ion detection and cell imaging were exploited.Further, using four representative CNDs, the size, quantum yield and the surfacepotential of CNDs were investigated how to affect the cell imaging applications.
Finally, we further developed novel kinds of CDs, named PDs. The PDspossessed both the fluorescent properties of carbon materials, and performance ofpolymers, which is significant for practical applications. The nonconjugated linearpolymers with easy dehydration groups were selected to form the PDs by moderatelycarbonizing, such as polyvinyl alcohol, polysaccharides, polyethylene imine. Theprepared PDs have single PL emission center, low cytotoxicity, which were applied incell imaging fields. Moreover, by precipitation assembling organic synthesized GQDs,the other kind of PDs were obtained. The PL mechanism was also exploited. Further,we investigated the PL behavior of crosslinked PDs system: polymer crosslinking caneffectively reduce the vibration and rotation of nonradiative relaxation consumption,thereby enhancing the fluorescence properties. At the end, the functionalnanocomposites were prepared using the fluorescent PDs: benefited from the PDs, thenanocomposites contained not only the PL emission center, but also the connectedpolymer chains.
In conclusion, from understanding PL mechanism of GQDs to producing CNDsand PDs in large scale, we followed the connection between theory and practicalapplication in this paper. The expanding the types, diverse synthesis, clear PLmechanism and novel aqueous applications of fluorescent carbon materials wereachieved in the present paper.
引文
[1] BAKER S N, BAKER G A. Luminescent carbon nanodots: emergent nanolights [J].Angew Chem Int Ed,2010,49:6726-6744.
[2] LI H, KANG Z, LIU Y, et al. Carbon nanodots: synthesis, properties and applications [J].Journal of Materials Chemistry,2012,22:24230-24253.
[3] WELSHER K, LIU Z, SHERLOCK S P, et al. A route to brightly fluorescent carbonnanotubes for near-infrared imaging in mice [J]. Nat Nanotechnol,2009,4:773-780.
[4] LI H, ZHANG Y, LUO Y, et al. Nano-C60: a novel, effective, fluorescent sensing platformfor biomolecular detection [J]. Small,2011,7:1562-1568.
[5] GAO M X, LIU C F, WU Z L, et al. A surfactant-assisted redox hydrothermal route toprepare highly photoluminescent carbon quantum dots with aggregation-induced emissionenhancement properties [J]. Chem Commun,2013,49:8015.
[6] YU S J, KANG M W, CHANG H C, et al. Bright fluorescent nanodiamonds: nophotobleaching and low cytotoxicity [J]. J Am Chem Soc,2005,127:17604-17605.
[7] CHANG I P, HWANG K C, CHIANG C S. Preparation of fluorescent magneticnanodiamonds and cellular imaging [J]. J Am Chem Soc,2008,130:15476-15481.
[8] MOCHALIN V N, SHENDEROVA O, HO D, et al. The properties and applications ofnanodiamonds [J]. Nat Nanotechnol,2012,7:11-23.
[9] GOKUS T, NAIR R R, BONETTI A, et al. Making graphene luminescent by oxygenplasma treatment [J]. ACS Nano,2009,3:3963-3968.
[10] DONG Y, SHAO J, CHEN C, et al. Blue luminescent graphene quantum dots andgraphene oxide prepared by tuning the carbonization degree of citric acid [J]. Carbon,2012,50:4738-4743.
[11] MEI Q, ZHANG Z. Photoluminescent graphene oxide ink to print sensors ontomicroporous membranes for versatile visualization bioassays [J]. Angew Chem Int Ed,2012,51:5602-5606.
[12] QIAN J, WANG D, CAI F H, et al. Observation of multiphoton-induced fluorescencefrom graphene oxide nanoparticles and applications in in vivo functional bioimaging [J].Angew Chem Int Ed,2012,51:10570-10575.
[13] WANG D, WANG L, DONG X, et al. Chemically tailoring graphene oxides intofluorescent nanosheets for Fe3+ion detection [J]. Carbon,2012,50:2147-2154.
[14] FENG L, YANG X, SHI X, et al. Polyethylene glycol and polyethylenimine dual-functionalized nano-graphene oxide for photothermally enhanced gene delivery [J]. Small,2013,9:1989-1997.
[15] GAN Z, XIONG S, WU X, et al. Mechanism of Photoluminescence from ChemicallyDerived Graphene Oxide: Role of Chemical Reduction [J]. Advanced Optical Materials,2013,1:926-932.
[16] LI J L, TANG B, YUAN B, et al. A review of optical imaging and therapy usingnanosized graphene and graphene oxide [J]. Biomaterials,2013,34:9519-9534.
[17] ZHANG X, WANG S, LIU M, et al. Size tunable fluorescent nano-graphite oxides:preparation and cell imaging applications [J]. Phys Chem Chem Phys,2013,15:19013-19018.
[18] CAO L, MEZIANI M J, SAHU S, et al. Photoluminescence properties of grapheneversus other carbon nanomaterials [J]. Acc Chem Res,2013,46:171-180.
[19] SHEN J, ZHU Y, YANG X, et al. Graphene quantum dots: emergent nanolights forbioimaging, sensors, catalysis and photovoltaic devices [J]. Chem Commun,2012,48:3686-3699.
[20] ZHANG Z, ZHANG J, CHEN N, et al. Graphene quantum dots: an emerging materialfor energy-related applications and beyond [J]. Energy&Environmental Science,2012,5:8869.
[21] LI L-S, YAN X. Colloidal Graphene Quantum Dots [J]. The Journal of PhysicalChemistry Letters,2010,1:2572-2576.
[22] LI L, WU G, YANG G, et al. Focusing on luminescent graphene quantum dots: currentstatus and future perspectives [J]. Nanoscale,2013,5:4015-4039.
[23] BACON M, BRADLEY S J, NANN T. Graphene Quantum Dots [J]. Particle&ParticleSystems Characterization,2014,31:415-428.
[24] LIN L, RONG M, LUO F, et al. Luminescent graphene quantum dots as new fluorescentmaterials for environmental and biological applications [J]. TrAC Trends in AnalyticalChemistry,2014,54:83-102.
[25] ZHOU X, GUO S, ZHANG J. Solution-processable graphene quantum dots [J].Chemphyschem,2013,14:2627-2640.
[26] XU X, RAY R, GU Y, et al. Electrophoretic analysis and purification of fluorescentsingle-walled carbon nanotube fragments [J]. J Am Chem Soc,2004,126:12736-12737.
[27] PONOMARENKO L A, SCHEDIN F, KATSNELSON M I, et al. Chaotic Dirac billiardin graphene quantum dots [J]. Science,2008,320:356-358.
[28] PAN D, ZHANG J, LI Z, et al. Hydrothermal route for cutting graphene sheets into blue-luminescent graphene quantum dots [J]. Adv Mater,2010,22:734-738.
[29] SHEN J, ZHU Y, CHEN C, et al. Facile preparation and upconversion luminescence ofgraphene quantum dots [J]. Chem Commun,2011,47:2580-2582.
[30] ZHAO J, CHEN G, ZHU L, et al. Graphene quantum dots-based platform for thefabrication of electrochemical biosensors [J]. Electrochemistry Communications,2011,13:31-33.
[31] LI Y, HU Y, ZHAO Y, et al. An electrochemical avenue to green-luminescent graphenequantum dots as potential electron-acceptors for photovoltaics [J]. Adv Mater,2011,23:776-780.
[32] ZHU S, ZHANG J, QIAO C, et al. Strongly green-photoluminescent graphene quantumdots for bioimaging applications [J]. Chem Commun,2011,47:6858-6860.
[33] LIU R, WU D, FENG X, et al. Bottom-up fabrication of photoluminescent graphenequantum dots with uniform morphology [J]. J Am Chem Soc,2011,133:15221-15223.
[34] LEE J, KIM K, PARK W I, et al. Uniform graphene quantum dots patterned from self-assembled silica nanodots [J]. Nano Lett,2012,12:6078-6083.
[35] PENG J, GAO W, GUPTA B K, et al. Graphene quantum dots derived from carbonfibers [J]. Nano Lett,2012,12:844-849.
[36] DONG Y, CHEN C, ZHENG X, et al. One-step and high yield simultaneous preparationof single-and multi-layer graphene quantum dots from CX-72carbon black [J]. Journal ofMaterials Chemistry,2012,22:8764.
[37] LIN L, ZHANG S. Creating high yield water soluble luminescent graphene quantum dotsvia exfoliating and disintegrating carbon nanotubes and graphite flakes [J]. Chem Commun,2012,48:10177-10179.
[38] LI L-L, JI J, FEI R, et al. A Facile Microwave Avenue to Electrochemiluminescent Two-Color Graphene Quantum Dots [J]. Advanced Functional Materials,2012,22:2971-2979.
[39] ZHOU X, ZHANG Y, WANG C, et al. Photo-Fenton reaction of graphene oxide: a newstrategy to prepare graphene quantum dots for DNA cleavage [J]. ACS Nano,2012,6:6592-6599.
[40] DONG Y, LI G, ZHOU N, et al. Graphene quantum dot as a green and facile sensor forfree chlorine in drinking water [J]. Anal Chem,2012,84:8378-8382.
[41] SUN Y P, ZHOU B, LIN Y, et al. Quantum-sized carbon dots for bright and colorfulphotoluminescence [J]. J Am Chem Soc,2006,128:7756-7757.
[42] CAO L, WANG X, MEZIANI M J, et al. Carbon dots for multiphoton bioimaging [J]. JAm Chem Soc,2007,129:11318-11319.
[43] LIU H, YE T, MAO C. Fluorescent carbon nanoparticles derived from candle soot [J].Angew Chem Int Ed,2007,46:6473-6475.
[44] ZHOU J, BOOKER C, LI R, et al. An electrochemical avenue to blue luminescentnanocrystals from multiwalled carbon nanotubes (MWCNTs)[J]. J Am Chem Soc,2007,129:744-745.
[45] ZHAO Q L, ZHANG Z L, HUANG B H, et al. Facile preparation of low cytotoxicityfluorescent carbon nanocrystals by electrooxidation of graphite [J]. Chem Commun,2008,44:5116-5118.
[46] LI H, HE X, KANG Z, et al. Water-soluble fluorescent carbon quantum dots andphotocatalyst design [J]. Angew Chem Int Ed,2010,49:4430-4434.
[47] HU S-L, NIU K-Y, SUN J, et al. One-step synthesis of fluorescent carbon nanoparticlesby laser irradiation [J]. Journal of Materials Chemistry,2009,19:484.
[48] LIU R, WU D, LIU S, et al. An aqueous route to multicolor photoluminescent carbondots using silica spheres as carriers [J]. Angew Chem Int Ed,2009,48:4598-4601.
[49] RAY S C, SAHA A, JANA N R, et al. Fluorescent Carbon Nanoparticles: Synthesis,Characterization, and Bioimaging Application [J]. Journal Of Physical Chemistry C,2009,113:18546-18551.
[50] QIAO Z A, WANG Y, GAO Y, et al. Commercially activated carbon as the source forproducing multicolor photoluminescent carbon dots by chemical oxidation [J]. ChemCommun,2010,46:8812-8814.
[51] E Y F, BAI L L, FAN L Z, et al. Electrochemically generated fluorescent fullerene[60]nanoparticles as a new and viable bioimaging platform [J]. Journal of Materials Chemistry,2011,21:819-823.
[52] WANG F, XIE Z, ZHANG H, et al. Highly Luminescent Organosilane-FunctionalizedCarbon Dots [J]. Advanced Functional Materials,2011,21:1027-1031.
[53] YANG Z C, WANG M, YONG A M, et al. Intrinsically fluorescent carbon dots withtunable emission derived from hydrothermal treatment of glucose in the presence ofmonopotassium phosphate [J]. Chem Commun,2011,47:11615-11617.
[54] CHANDRA S, MITRA S, LAHA D, et al. Fabrication of multi-structure nanocarbonsfrom carbon xerogel: a unique scaffold towards bio-imaging [J]. Chem Commun,2011,47:8587-8589.
[55] LIU C, ZHANG P, ZHAI X, et al. Nano-carrier for gene delivery and bioimaging basedon carbon dots with PEI-passivation enhanced fluorescence [J]. Biomaterials,2012,33:3604-3613.
[56] HSU P C, CHANG H T. Synthesis of high-quality carbon nanodots from hydrophiliccompounds: role of functional groups [J]. Chem Commun,2012,48:3984-3986.
[57] SONG Y C, SHI W, CHEN W, et al. Fluorescent carbon nanodots conjugated with folicacid for distinguishing folate-receptor-positive cancer cells from normal cells [J]. Journal ofMaterials Chemistry,2012,22:12568-12573.
[58] LAI C W, HSIAO Y H, PENG Y K, et al. Facile synthesis of highly emissive carbondots from pyrolysis of glycerol; gram scale production of carbon dots/SiO2for cell imagingand drug release [J]. Journal of Materials Chemistry,2012,22:14403-14409.
[59] ZHAI X, ZHANG P, LIU C, et al. Highly luminescent carbon nanodots by microwave-assisted pyrolysis [J]. Chem Commun,2012,48:7955-7957.
[60] ZHANG Z, HAO J H, ZHANG J, et al. Protein as the source for synthesizing fluorescentcarbon dots by a one-pot hydrothermal route [J]. RSC Advances,2012,2:8599-8601.
[61] CHEN B, LI F, LI S, et al. Large scale synthesis of photoluminescent carbon nanodotsand their application for bioimaging [J]. Nanoscale,2013,5:1967-1971.
[62] ZHU S, MENG Q, WANG L, et al. Highly photoluminescent carbon dots for multicolorpatterning, sensors, and bioimaging [J]. Angew Chem Int Ed,2013,52:3953-3957.
[63] BHUNIA S K, SAHA A, MAITY A R, et al. Carbon nanoparticle-based fluorescentbioimaging probes [J]. Sci Rep,2013,3:1473.
[64] SAHU S, BEHERA B, MAITI T K, et al. Simple one-step synthesis of highlyluminescent carbon dots from orange juice: application as excellent bio-imaging agents [J].Chem Commun,2012,48:8835-8837.
[65] SUN D, BAN R, ZHANG P H, et al. Hair fiber as a precursor for synthesizing of sulfur-and nitrogen-co-doped carbon dots with tunable luminescence properties [J]. Carbon,2013,64:424-434.
[66] WANG W, LI Y M, CHENG L, et al. Water-soluble and phosphorus-containing carbondots with strong green fluorescence for cell labeling [J]. Journal of Materials Chemistry B,2014,2:46-48.
[67] HUANG H, XU Y, TANG C-J, et al. Facile and green synthesis of photoluminescentcarbon nanoparticles for cellular imaging [J]. New Journal of Chemistry,2014,38:784.
[68] WU C, CHIU D T. Highly fluorescent semiconducting polymer dots for biology andmedicine [J]. Angew Chem Int Ed,2013,52:3086-3109.
[69] ZHANG X, YU J, RONG Y, et al. High-intensity near-IR fluorescence insemiconducting polymer dots achieved by cascade FRET strategy [J]. Chemical Science,2013,4:2143.
[70] LIU S, TIAN J, WANG L, et al. Hydrothermal treatment of grass: a low-cost, greenroute to nitrogen-doped, carbon-rich, photoluminescent polymer nanodots as an effectivefluorescent sensing platform for label-free detection of Cu(II) ions [J]. Adv Mater,2012,24:2037-2041.
[71] ZHU S, ZHANG J, WANG L, et al. A general route to make non-conjugated linearpolymers luminescent [J]. Chem Commun,2012,48:10889-10891.
[72] LAI T, ZHENG E, CHEN L, et al. Hybrid carbon source for producing nitrogen-dopedpolymer nanodots: one-pot hydrothermal synthesis, fluorescence enhancement and highlyselective detection of Fe(III)[J]. Nanoscale,2013,5:8015-8021.
[73] FAN R-J, SUN Q, ZHANG L, et al. Photoluminescent carbon dots directly derived frompolyethylene glycol and their application for cellular imaging [J]. Carbon,2014,10.1016/j.carbon.2014.01.016.
[74] GU J, WANG W, ZHANG Q, et al. Synthesis of fluorescent carbon nanoparticles frompolyacrylamide for fast cellular endocytosis [J]. RSC Advances,2013,3:15589.
[75] LI W, ZHANG Z, KONG B, et al. Simple and green synthesis of nitrogen-dopedphotoluminescent carbonaceous nanospheres for bioimaging [J]. Angew Chem Int Ed,2013,52:8151-8155.
[76] YANG Y, CUI J, ZHENG M, et al. One-step synthesis of amino-functionalizedfluorescent carbon nanoparticles by hydrothermal carbonization of chitosan [J]. ChemCommun,2012,48:380-382.
[77] SUN Y, CAO W, LI S, et al. Ultrabright and multicolorful fluorescence of amphiphilicpolyethyleneimine polymer dots for efficiently combined imaging and therapy [J]. Sci Rep,2013,3:3036.
[78] DING D, GOH C C, FENG G, et al. Ultrabright organic dots with aggregation-inducedemission characteristics for real-time two-photon intravital vasculature imaging [J]. AdvMater,2013,10.1002/adma.201301938.
[79] LI K, QIN W, DING D, et al. Photostable fluorescent organic dots with aggregation-induced emission (AIE dots) for noninvasive long-term cell tracing [J]. Sci Rep,2013,3:1150.
[80] ZHANG X, WANG S, XU L, et al. Biocompatible polydopamine fluorescent organicnanoparticles: facile preparation and cell imaging [J]. Nanoscale,2012,4:5581-5584.
[81] QIAO Z A, HUO Q, CHI M, et al. A "ship-in-a-bottle" approach to synthesis of polymerdots@silica or polymer dots@carbon core-shell nanospheres [J]. Adv Mater,2012,24:6017-6021.
[82] GUO C X, XIE J, WANG B, et al. A new class of fluorescent-dots: long luminescentlifetime bio-dots self-assembled from DNA at low temperatures [J]. Sci Rep,2013,3:2957.
[83] GAN Z X, XIONG S J, WU X L, et al. Mechanism of Photoluminescence fromChemically Derived Graphene Oxide: Role of Chemical Reduction [J]. Advanced OpticalMaterials,2013,1:926-932.
[84] BAO L, ZHANG Z L, TIAN Z Q, et al. Electrochemical tuning of luminescent carbonnanodots: from preparation to luminescence mechanism [J]. Adv Mater,2011,23:5801-5806.
[85] PAN D, ZHANG J, LI Z, et al. Observation of pH-, solvent-, spin-, and excitation-dependent blue photoluminescence from carbon nanoparticles [J]. Chem Commun,2010,46:3681-3683.
[86] ZHANG Y, GONCALVES H, DA SILVA J C, et al. Metal-enhanced photoluminescencefrom carbon nanodots [J]. Chem Commun,2011,47:5313-5315.
[87] YU P, WEN X, TOH Y-R, et al. Temperature-Dependent Fluorescence in Carbon Dots[J]. The Journal of Physical Chemistry C,2012,116:25552-25557.
[88] WANG L, ZHU S-J, WANG H-Y, et al. Unraveling bright molecule-like state and darkintrinsic state in green-fluorescence graphene quantum dots via ultrafast spectroscopy [J].Advanced Optical Materials,2013,1:264-271.
[89] EDA G, LIN Y Y, MATTEVI C, et al. Blue photoluminescence from chemically derivedgraphene oxide [J]. Adv Mater,2010,22:505-509.
[90] SHANG J, MA L, LI J, et al. The origin of fluorescence from graphene oxide [J]. SciRep,2012,2:792.
[91] WANG L, WANG H Y, WANG Y, et al. Direct observation of quantum-confinedgraphene-like states and novel hybrid states in graphene oxide by transient spectroscopy [J].Adv Mater,2013,25:6539-6545.
[92] KIM S, HWANG S W, KIM M K, et al. Anomalous behaviors of visible luminescencefrom graphene quantum dots: interplay between size and shape [J]. ACS Nano,2012,6:8203-8208.
[93] XU Q, ZHOU Q, HUA Z, et al. Single-particle spectroscopic measurements offluorescent graphene quantum dots [J]. ACS Nano,2013,7:10654-10661.
[94] TETSUKA H, ASAHI R, NAGOYA A, et al. Optically tunable amino-functionalizedgraphene quantum dots [J]. Adv Mater,2012,24:5333-5338.
[95] JIN S H, KIM DA H, JUN G H, et al. Tuning the photoluminescence of graphenequantum dots through the charge transfer effect of functional groups [J]. ACS Nano,2013,7:1239-1245.
[96] ZHU S, ZHANG J, TANG S, et al. Surface chemistry routes to modulate thephotoluminescence of graphene quantum dots: from fuorescence mechanism to up-conversionbioimaging applications [J]. Advanced Functional Materials,2012,22:4732-4740.
[97] ZHENG H, WANG Q, LONG Y, et al. Enhancing the luminescence of carbon dots witha reduction pathway [J]. Chem Commun,2011,47:10650-10652.
[98] LIU F, JANG M H, HA H D, et al. Facile synthetic method for pristine graphenequantum dots and graphene oxide quantum dots: origin of blue and green luminescence [J].Adv Mater,2013,25:3657-3662.
[99] LINGAM K, PODILA R, QIAN H, et al. Evidence for edge-state photoluminescence ingraphene quantum dots [J]. Advanced Functional Materials,2013,23:5062-5065.
[100] WANG X, CAO L, LU F, et al. Photoinduced electron transfers with carbon dots [J].Chem Commun,2009,10.1039/b906252a:3774-3776.
[101] YANG S T, WANG X, WANG H, et al. Carbon dots as nontoxic and high-performancefluorescence imaging agents [J]. J Phys Chem C Nanomater Interfaces,2009,113:18110-18114.
[102] WEN X, YU P, TOH Y-R, et al. Intrinsic and extrinsic fluorescence in carbon nanodots:ultrafast time-resolved fluorescence and carrier dynamics [J]. Advanced Optical Materials,2013,1:173-178.
[103] BOURLINOS A B, STASSINOPOULOS A, ANGLOS D, et al. Surface functionalizedcarbogenic quantum dots [J]. Small,2008,4:455-458.
[104] VINCI J C, FERRER I M, SEEDHOUSE S J, et al. Hidden properties of carbon dotsrevealed after HPLC fractionation [J]. The Journal of Physical Chemistry Letters,2013,4:239-243.
[105] TAN D, ZHOU S, SHIMOTSUMA Y, et al. Effect of UV irradiation onphotoluminescence of carbon dots [J]. Optical Materials Express,2014,4:213.
[106] CHEN S, LIU J W, CHEN M L, et al. Unusual emission transformation of graphenequantum dots induced by self-assembled aggregation [J]. Chem Commun,2012,48:7637-7639.
[107] YANG F, ZHAO M, ZHENG B, et al. Influence of pH on the fluorescence properties ofgraphene quantum dots using ozonation pre-oxide hydrothermal synthesis [J]. Journal ofMaterials Chemistry,2012,22:25471.
[108] WANG L, ZHU S J, WANG H Y, et al. Common origin of green luminescence incarbon nanodots and graphene quantum dots [J]. ACS Nano,2014,8:2541-2547.
[109] DAS S K, LIU Y, YEOM S, et al. Single-particle fluorescence intensity fluctuations ofcarbon nanodots [J]. Nano Lett,2014,14:620-625.
[110] BOURLINOS A B, STASSINOPOULOS A, ANGLOS D, et al. PhotoluminescentCarbogenic Dots [J]. Chemistry of Materials,2008,20:4539-4541.
[111] BOURLINOS A B, GEORGAKILAS V, ZBORIL R, et al. Pyrolytic formation andphotoluminescence properties of a new layered carbonaceous material with graphite oxide-mimicking characteristics [J]. Carbon,2009,47:519-526.
[112] ZHENG L, CHI Y, DONG Y, et al. Electrochemiluminescence of water-soluble carbonnanocrystals released electrochemically from graphite [J]. J Am Chem Soc,2009,131:4564-4565.
[113] ZHOU J, ZHOU X, LI R, et al. Electronic structure and luminescence center of blueluminescent carbon nanocrystals [J]. Chemical Physics Letters,2009,474:320-324.
[114] ZHU H, WANG X, LI Y, et al. Microwave synthesis of fluorescent carbonnanoparticles with electrochemiluminescence properties [J]. Chem Commun,2009,10.1039/b907612c:5118-5120.
[115] MAO X J, ZHENG H Z, LONG Y J, et al. Study on the fluorescence characteristics ofcarbon dots [J]. Spectrochim Acta A Mol Biomol Spectrosc,2010,75:553-557.
[116] WANG F, XIE Z, ZHANG H, et al. Highly Luminescent Organosilane-FunctionalizedCarbon Dots [J]. Advanced Functional Materials,2011,21:1027-1031.
[117] HOLA K, BOURLINOS A B, KOZAK O, et al. Photoluminescence effects of graphiticcore size and surface functional groups in carbon dots: COO induced red-shift emission [J].Carbon,2014,70:279-286.
[118] KRYSMANN M J, KELARAKIS A, DALLAS P, et al. Formation mechanism ofcarbogenic nanoparticles with dual photoluminescence emission [J]. J Am Chem Soc,2012,134:747-750.
[119] LIN Z, XUE W, CHEN H, et al. Peroxynitrous-acid-induced chemiluminescence offluorescent carbon dots for nitrite sensing [J]. Anal Chem,2011,83:8245-8251.
[120] LI C, ZHU Y, ZHANG X, et al. Metal-enhanced fluorescence of carbon dots adsorbedAg@SiO2core-shell nanoparticles [J]. RSC Advances,2012,2:1765.
[121] DONG Y, PANG H, YANG H B, et al. Carbon-based dots co-doped with nitrogen andsulfur for high quantum yield and excitation-independent emission [J]. Angew Chem Int Ed,2013,52:7800-7804.
[122] LI F, LIU C, YANG J, et al. Mg/N double doping strategy to fabricate extremely highluminescent carbon dots for bioimaging [J]. RSC Advances,2014,4:3201.
[123] RAN X, SUN H, PU F, et al. Ag nanoparticle-decorated graphene quantum dots forlabel-free, rapid and sensitive detection of Ag+and biothiols [J]. Chem Commun,2013,49:1079-1081.
[124] QU Z B, ZHOU X, GU L, et al. Boronic acid functionalized graphene quantum dots asa fluorescent probe for selective and sensitive glucose determination in microdialysate [J].Chem Commun,2013,49:9830-9832.
[125] CHANDRA S, PATRA P, PATHAN S H, et al. Luminescent S-doped carbon dots: anemergent architecture for multimodal applications [J]. Journal of Materials Chemistry B,2013,1:2375.
[126] KWON W, LIM J, LEE J, et al. Sulfur-incorporated carbon quantum dots with a stronglong-wavelength absorption band [J]. Journal of Materials Chemistry C,2013,1:2002.
[127] QU D, ZHENG M, DU P, et al. Highly luminescent S, N co-doped graphene quantumdots with broad visible absorption bands for visible light photocatalysts [J]. Nanoscale,2013,5:12272-12277.
[128] LIU S, YU B, ZHANG T. Nitrogen-doped carbon nanodots as a reducing agent tosynthesize Ag nanoparticles for non-enzymatic hydrogen peroxide detection [J]. RSCAdvances,2014,4:544.
[129] NIU J, GAO H, WANG L, et al. Facile synthesis and optical properties of nitrogen-doped carbon dots [J]. New Journal of Chemistry,2014,38:1522-1527.
[130] YANG Z, XU M, LIU Y, et al. Nitrogen-doped, carbon-rich, highly photoluminescentcarbon dots from ammonium citrate [J]. Nanoscale,2014,6:1890-1895.
[131] LI Y, ZHAO Y, CHENG H, et al. Nitrogen-doped graphene quantum dots with oxygen-rich functional groups [J]. J Am Chem Soc,2012,134:15-18.
[132] HU C, LIU Y, YANG Y, et al. One-step preparation of nitrogen-doped graphenequantum dots from oxidized debris of graphene oxide [J]. Journal of Materials Chemistry B,2013,1:39.
[133] GUPTA V, CHAUDHARY N, SRIVASTAVA R, et al. Luminscent graphene quantumdots for organic photovoltaic devices [J]. J Am Chem Soc,2011,133:9960-9963.
[134] DUTTA M, SARKAR S, GHOSH T, et al. ZnO/graphene quantum dot solid-state solarcell [J]. The Journal of Physical Chemistry C,2012,116:20127-20131.
[135] CHEN L, GUO C X, ZHANG Q, et al. Graphene quantum-dot-doped polypyrrolecounter electrode for high-performance dye-sensitized solar cells [J]. ACS Appl MaterInterfaces,2013,5:2047-2052.
[136] MIRTCHEV P, HENDERSON E J, SOHEILNIA N, et al. Solution phase synthesis ofcarbon quantum dots as sensitizers for nanocrystalline TiO2solar cells [J]. Journal ofMaterials Chemistry,2012,22:1265.
[137] TANG L, JI R, CAO X, et al. Deep ultraviolet photoluminescence of water-soluble self-passivated graphene quantum dots [J]. ACS Nano,2012,6:5102-5110.
[138] KWON W, DO S, LEE J, et al. Freestanding Luminescent Films of Nitrogen-RichCarbon Nanodots toward Large-Scale Phosphor-Based White-Light-Emitting Devices [J].Chemistry of Materials,2013,25:1893-1899.
[139] WANG F, CHEN Y H, LIU C Y, et al. White light-emitting devices based on carbondots' electroluminescence [J]. Chem Commun,2011,47:3502-3504.
[140] ZHANG X, ZHANG Y, WANG Y, et al. Color-switchable electroluminescence ofcarbon dot light-emitting diodes [J]. ACS Nano,2013,7:11234-11241.
[141] SHEN J, ZHU Y, YANG X, et al. One-pot hydrothermal synthesis of graphenequantum dots surface-passivated by polyethylene glycol and their photoelectric conversionunder near-infrared light [J]. New Journal of Chemistry,2012,36:97.
[142] CHOI H, KO S-J, CHOI Y, et al. Versatile surface plasmon resonance of carbon-dot-supported silver nanoparticles in polymer optoelectronic devices [J]. Nature Photonics,2013,7:732-738.
[143] SON D I, KWON B W, PARK D H, et al. Emissive ZnO-graphene quantum dots forwhite-light-emitting diodes [J]. Nat Nanotechnol,2012,7:465-471.
[144] CHENG S H, WENG T M, LU M L, et al. All carbon-based photodetectors: an eminentintegration of graphite quantum dots and two dimensional graphene [J]. Sci Rep,2013,3:2694.
[145] KOU L, LI F, CHEN W, et al. Synthesis of blue light-emitting graphene quantum dotsand their application in flexible nonvolatile memory [J]. Organic Electronics,2013,14:1447-1451.
[146] LEE E, RYU J, JANG J. Fabrication of graphene quantum dots via size-selectiveprecipitation and their application in upconversion-based DSSCs [J]. Chem Commun,2013,49:9995-9997.
[147] LIU W-W, FENG Y-Q, YAN X-B, et al. Superior Micro-Supercapacitors Based onGraphene Quantum Dots [J]. Advanced Functional Materials,2013,23:4111-4122.
[148] LIU W, YAN X, CHEN J, et al. Novel and high-performance asymmetric micro-supercapacitors based on graphene quantum dots and polyaniline nanofibers [J]. Nanoscale,2013,5:6053-6062.
[149] ZHUO S, SHAO M, LEE S T. Upconversion and downconversion fluorescent graphenequantum dots: ultrasonic preparation and photocatalysis [J]. ACS Nano,2012,6:1059-1064.
[150] ZHENG M, XIE Z, QU D, et al. On-off-on fluorescent carbon dot nanosensor forrecognition of chromium(VI) and ascorbic acid based on the inner filter effect [J]. ACS ApplMater Interfaces,2013,5:13242-13247.
[151] LIN Z, XUE W, CHEN H, et al. Classical oxidant induced chemiluminescence offluorescent carbon dots [J]. Chem Commun,2012,48:1051-1053.
[152] LU W, QIN X, LIU S, et al. Economical, green synthesis of fluorescent carbonnanoparticles and their use as probes for sensitive and selective detection of mercury(II) ions[J]. Anal Chem,2012,84:5351-5357.
[153] ZHAO H X, LIU L Q, LIU Z D, et al. Highly selective detection of phosphate in verycomplicated matrixes with an off-on fluorescent probe of europium-adjusted carbon dots [J].Chem Commun,2011,47:2604-2606.
[154] WEI W, XU C, REN J, et al. Sensing metal ions with ion selectivity of a crown etherand fluorescence resonance energy transfer between carbon dots and graphene [J]. ChemCommun,2012,48:1284-1286.
[155] ZHU A, DING C, TIAN Y. A two-photon ratiometric fluorescence probe for cupricions in live cells and tissues [J]. Sci Rep,2013,3:2933.
[156] KONG B, ZHU A, DING C, et al. Carbon dot-based inorganic-organic nanosystem fortwo-photon imaging and biosensing of pH variation in living cells and tissues [J]. Adv Mater,2012,24:5844-5848.
[157] ZHU A, QU Q, SHAO X, et al. Carbon-dot-based dual-emission nanohybrid produces aratiometric fluorescent sensor for in vivo imaging of cellular copper ions [J]. Angew ChemInt Ed,2012,51:7185-7189.
[158] SREEPRASAD T S, RODRIGUEZ A A, COLSTON J, et al. Electron-tunnelingmodulation in percolating network of graphene quantum dots: fabrication, phenomenologicalunderstanding, and humidity/pressure sensing applications [J]. Nano Lett,2013,13:1757-1763.
[159] ZHAO H, CHANG Y, LIU M, et al. A universal immunosensing strategy based onregulation of the interaction between graphene and graphene quantum dots [J]. ChemCommun,2013,49:234-236.
[160] BAI J M, ZHANG L, LIANG R P, et al. Graphene quantum dots combined witheuropium ions as photoluminescent probes for phosphate sensing [J]. Chemistry,2013,19:3822-3826.
[161] HUANG H, LIAO L, XU X, et al. The electron-transfer based interaction betweentransition metal ions and photoluminescent graphene quantum dots (GQDs): a platform formetal ion sensing [J]. Talanta,2013,117:152-157.
[162] LIU J J, ZHANG X L, CONG Z X, et al. Glutathione-functionalized graphene quantumdots as selective fluorescent probes for phosphate-containing metabolites [J]. Nanoscale,2013,5:1810-1815.
[163] LU J, YAN M, GE L, et al. Electrochemiluminescence of blue-luminescent graphenequantum dots and its application in ultrasensitive aptasensor for adenosine triphosphatedetection [J]. Biosens Bioelectron,2013,47:271-277.
[164] SUN H, GAO N, WU L, et al. Highly photoluminescent amino-functionalized graphenequantum dots used for sensing copper ions [J]. Chemistry,2013,19:13362-13368.
[165] WANG X, CHEN L, SU X, et al. Electrochemical immunosensor with graphenequantum dots and apoferritin-encapsulated Cu nanoparticles double-assisted signalamplification for detection of avian leukosis virus subgroup J [J]. Biosens Bioelectron,2013,47:171-177.
[166] ZHOU L, GENG J, LIU B. Graphene quantum dots from polycyclic aromatichydrocarbon for bioimaging and sensing of Fe3+and hydrogen peroxide [J]. Particle&Particle Systems Characterization,2013,30:1086-1092.
[167] ANANTHANARAYANAN A, WANG X, ROUTH P, et al. Facile synthesis ofgraphene quantum dots from3D graphene and their application for Fe3+sensing [J]. AdvancedFunctional Materials,2014,24:3021-3026.
[168] WANG F, GU Z, LEI W, et al. Graphene quantum dots as a fluorescent sensingplatform for highly efficient detection of copper(II)ions [J]. Sensors and Actuators B:Chemical,2014,190:516-522.
[169] WU Z, LI W, CHEN J, et al. A graphene quantum dot-based method for the highlysensitive and selective fluorescence turn on detection of biothiols [J]. Talanta,2014,119:538-543.
[170] LIU J, LI J, JIANG Y, et al. Combination of pi-pi stacking and electrostatic repulsionbetween carboxylic carbon nanoparticles and fluorescent oligonucleotides for rapid andsensitive detection of thrombin [J]. Chem Commun,2011,47:11321-11323.
[171] YIN B, DENG J, PENG X, et al. Green synthesis of carbon dots with down-and up-conversion fluorescent properties for sensitive detection of hypochlorite with a dual-readoutassay [J]. Analyst,2013,138:6551-6557.
[172] QIN X, LU W, ASIRI A M, et al. Green, low-cost synthesis of photoluminescentcarbon dots by hydrothermal treatment of willow bark and their application as an effectivephotocatalyst for fabricating Au nanoparticles–reduced graphene oxide nanocomposites forglucose detection [J]. Catalysis Science&Technology,2013,3:1027.
[173] WANG Q, LIU X, ZHANG L, et al. Microwave-assisted synthesis of carbon nanodotsthrough an eggshell membrane and their fluorescent application [J]. Analyst,2012,137:5392-5397.
[174] HUANG H, LV J J, ZHOU D L, et al. One-pot green synthesis of nitrogen-dopedcarbon nanoparticles as fluorescent probes for mercury ions [J]. RSC Advances,2013,3:21691-21696.
[175] JIA X, LI J, WANG E. One-pot green synthesis of optically pH-sensitive carbon dotswith upconversion luminescence [J]. Nanoscale,2012,4:5572-5575.
[176] QU S, CHEN H, ZHENG X, et al. Ratiometric fluorescent nanosensor based on watersoluble carbon nanodots with multiple sensing capacities [J]. Nanoscale,2013,5:5514-5518.
[177] FAN L, HU Y, WANG X, et al. Fluorescence resonance energy transfer quenching atthe surface of graphene quantum dots for ultrasensitive detection of TNT [J]. Talanta,2012,101:192-197.
[178] GUO Y, WANG Z, SHAO H, et al. Hydrothermal synthesis of highly fluorescentcarbon nanoparticles from sodium citrate and their use for the detection of mercury ions [J].Carbon,2013,52:583-589.
[179] ZHANG Y-L, WANG L, ZHANG H-C, et al. Graphitic carbon quantum dots as afluorescent sensing platform for highly efficient detection of Fe3+ions [J]. RSC Advances,2013,3:3733.
[180] ZHANG C, LIU Y, XIONG X Q, et al. Three-dimensional nanographene based ontriptycene: synthesis and its application in fluorescence imaging [J]. Org Lett,2012,14:5912-5915.
[181] ZHANG M, BAI L, SHANG W, et al. Facile synthesis of water-soluble, highlyfluorescent graphene quantum dots as a robust biological label for stem cells [J]. Journal ofMaterials Chemistry,2012,22:7461.
[182] ABDULLAH AL N, LEE J E, IN I, et al. Target delivery and cell imaging usinghyaluronic acid-functionalized graphene quantum dots [J]. Mol Pharm,2013,10:3736-3744.
[183] CHEN X, ZHOU X, HAN T, et al. Stabilization and induction of oligonucleotide i-motif structure via graphene quantum dots [J]. ACS Nano,2013,7:531-537.
[184] DENG L, LIU L, ZHU C, et al. Hybrid gold nanocube@silica@graphene-quantum-dotsuperstructures: synthesis and specific cell surface protein imaging applications [J]. ChemCommun,2013,49:2503-2505.
[185] WU C, WANG C, HAN T, et al. Insight into the cellular internalization andcytotoxicity of graphene quantum dots [J]. Adv Healthc Mater,2013,2:1613-1619.
[186] WU X, TIAN F, WANG W, et al. Fabrication of highly fluorescent graphene quantumdots using L-glutamic acid for imaging and sensing [J]. J Mater Chem C Mater Opt ElectronDevices,2013,1:4676-4684.
[187] YANG K, FENG L, SHI X, et al. Nano-graphene in biomedicine: theranosticapplications [J]. Chem Soc Rev,2013,42:530-547.
[188] ZHENG X T, THAN A, ANANTHANARAYA A, et al. Graphene quantum dots asuniversal fluorophores and their use in revealing regulated trafficking of insulin receptors inadipocytes [J]. ACS Nano,2013,7:6278-6286.
[189] TAO H, YANG K, MA Z, et al. In Vivo NIR Fluorescence imaging, biodistribution,and toxicology of photoluminescent carbon dots produced from carbon nanotubes andgraphite [J]. Small,2011,10.1002/smll.201101706.
[190] KUMAR V, TOFFOLI G, RIZZOLIO F. Fluorescent carbon nanoparticles in medicinefor cancer therapy [J]. ACS Medicinal Chemistry Letters,2013,4:1012-1013.
[191] WANG W, LI Y, CHENG L, et al. Water-soluble and phosphorus-containing carbondots with strong green fluorescence for cell labeling [J]. Journal of Materials Chemistry B,2014,2:46.
[192] YAN F, ZOU Y, WANG M, et al. Highly photoluminescent carbon dots-basedfluorescent chemosensors for sensitive and selective detection of mercury ions andapplication of imaging in living cells [J]. Sensors and Actuators B: Chemical,2014,192:488-495.
[193] LIU Y, WU P. Graphene quantum dot hybrids as efficient metal-free electrocatalyst forthe oxygen reduction reaction [J]. ACS Appl Mater Interfaces,2013,5:3362-3369.
[194] TANG J, KONG B, WU H, et al. Carbon nanodots featuring efficient FRET for real-time monitoring of drug delivery and two-photon imaging [J]. Adv Mater,2013,25:6569-6574.
[195] HUANG X, ZHANG F, ZHU L, et al. Effect of injection routes on the biodistribution,clearance, and tumor uptake of carbon dots [J]. ACS Nano,2013,7:5684-5693.
[196] WU L, LUDERER M, YANG X, et al. Surface passivation of carbon nanoparticles withbranched macromolecules influences near infrared bioimaging [J]. Theranostics,2013,3:677-686.
[197] LUO P G, SAHU S, YANG S-T, et al. Carbon “quantum” dots for optical bioimaging[J]. Journal of Materials Chemistry B,2013,1:2116.
[198] XU H, LI Q, WANG L, et al. Nanoscale optical probes for cellular imaging [J]. ChemSoc Rev,2014,10.1039/c3cs60309a.
[199] CHEN M, YIN M. Design and development of fluorescent nanostructures forbioimaging [J]. Progress in Polymer Science,2014,39:365-395.
[200] XIE Z, WANG F, LIU C Y. Organic-inorganic hybrid functional carbon dot gel glasses[J]. Adv Mater,2012,24:1716-1721.
[201] CHENG H, ZHAO Y, FAN Y, et al. Graphene-quantum-dot assembled nanotubes: anew platform for efficient Raman enhancement [J]. ACS Nano,2012,6:2237-2244.
[202] DING Y, CHENG H, ZHOU C, et al. Functional microspheres of graphene quantumdots [J]. Nanotechnology,2012,23:255605.
[203] ZHANG G, ZHANG H, ZHANG X, et al. Embedding graphene nanoparticles intopoly(N,N′-dimethylacrylamine) to prepare transparent nanocomposite films with highrefractive index [J]. Journal of Materials Chemistry,2012,22:21218.
[204] QU S, WANG X, LU Q, et al. A biocompatible fluorescent ink based on water-solubleluminescent carbon nanodots [J]. Angew Chem Int Ed,2012,51:12215-12218.
[205] WANG X, CAO L, YANG S T, et al. Bandgap-like strong fluorescence infunctionalized carbon nanoparticles [J]. Angew Chem Int Ed,2010,49:5310-5314.
[206] ZHU S, ZHANG J, LIU X, et al. Graphene quantum dots with controllable surfaceoxidation, tunable fluorescence and up-conversion emission [J]. RSC Advances,2012,2:2717.
[207] LIU Q, GUO B, RAO Z, et al. Strong two-photon-induced fluorescence fromphotostable, biocompatible nitrogen-doped graphene quantum dots for cellular and deep-tissue imaging [J]. Nano Lett,2013,13:2436-2441.
[208] SUN Y, WANG S, LI C, et al. Large scale preparation of graphene quantum dots fromgraphite with tunable fluorescence properties [J]. Phys Chem Chem Phys,2013,15:9907-9913.
[209] YE R, XIANG C, LIN J, et al. Coal as an abundant source of graphene quantum dots [J].Nat Commun,2013,4:2943.
[210] GAN Z, WU X, ZHOU G, et al. Is There real upconversion photoluminescence fromgraphene quantum dots?[J]. Advanced Optical Materials,2013,1:554-558.
[211] LUO P, JI Z, LI C, et al. Aryl-modified graphene quantum dots with enhancedphotoluminescence and improved pH tolerance [J]. Nanoscale,2013,5:7361-7367.
[212] LI X, LAU S P, TANG L, et al. Multicolour light emission from chlorine-dopedgraphene quantum dots [J]. Journal of Materials Chemistry C,2013,1:7308.
[213] XUE Q, HUANG H, WANG L, et al. Nearly monodisperse graphene quantum dotsfabricated by amine-assisted cutting and ultrafiltration [J]. Nanoscale,2013,5:12098-12103.
[214] SUN H, WU L, GAO N, et al. Improvement of photoluminescence of graphenequantum dots with a biocompatible photochemical reduction pathway and its bioimagingapplication [J]. ACS Appl Mater Interfaces,2013,5:1174-1179.
[215] QIAN Z, MA J, SHAN X, et al. Surface functionalization of graphene quantum dotswith small organic molecules from photoluminescence modulation to bioimaging applications:an experimental and theoretical investigation [J]. RSC Advances,2013,3:14571.
[216] PAN D, GUO L, ZHANG J, et al. Cutting sp2clusters in graphene sheets into colloidalgraphene quantum dots with strong green fluorescence [J]. Journal of Materials Chemistry,2012,22:3314.
[217] JIANG F, CHEN D, LI R, et al. Eco-friendly synthesis of size-controllable amine-functionalized graphene quantum dots with antimycoplasma properties [J]. Nanoscale,2013,5:1137-1142.
[218] SONG Y, ZHU S, XIANG S, et al. Investigation into the fluorescence quenchingbehaviors and applications of carbon dots [J]. Nanoscale,2014,10.1039/c4nr00029c.
[219] QIAO Z-A, WANG Y, GAO Y, et al. Commercially activated carbon as the source forproducing multicolor photoluminescent carbon dots by chemical oxidation [J]. ChemCommun,2010,46:8812-8814.
[220] IYER V S, WEHMEIER M, BRAND J D, et al. From Hexa-peri-hexabenzocoroneneto“Superacenes”[J]. Angew Chem Int Ed,1997,36:1604-1607.
[221] ITO S, WEHMEIER M, BRAND J D, et al. Synthesis and Self-Assembly ofFunctionalized Hexa-peri-hexabenzocoronenes [J]. Chemistry,2000,6:4327-4342.
[222] TOMOVIC Z, WATSON M D, MULLEN K. Superphenalene-based columnar liquidcrystals [J]. Angew Chem Int Ed,2004,43:755-758.
[223] SAMOR P, SEVERIN N, SIMPSON C D, et al. Epitaxial composite layers of electrondonors and acceptors from very large polycyclic aromatic hydrocarbons [J]. J Am Chem Soc,2002,124:9454-9457.
[224] SIMPSON C D, BRAND J D, BERRESHEIM A J, et al. Synthesis of a Giant222Carbon Graphite Sheet [J]. Chemistry-A European Journal,2002,8:1424-1429.
[225] ZHU S, ZHANG J, SONG Y, et al. Fluorescent Nanocomposite Based on PVAPolymer Dots [J]. Acta Chimica Sinica,2012,70:2311.
[226] ZHANG H, LIU Y, YAO D, et al. Hybridization of inorganic nanoparticles andpolymers to create regular and reversible self-assembly architectures [J]. Chem Soc Rev,2012,41:6066-6088.
[227] SUN H, ZHANG F, WEI H, et al. The effects of composition and surface chemistry onthe toxicity of quantum dots [J]. Journal of Materials Chemistry B,2013,1:6485.
[228] YAN X, CUI X, LI L S. Synthesis of large, stable colloidal graphene quantum dots withtunable size [J]. J Am Chem Soc,2010,132:5944-5945.
[229] YAMAGUCHI R, ITO S, LEE B S, et al. Functionalization of hexa-peri-hexabenzocoronenes: investigation of the substituent effects on a superbenzene [J]. ChemAsian J,2013,8:178-190.
[230] MUELLER M L, YAN X, DRAGNEA B, et al. Slow hot-carrier relaxation in colloidalgraphene quantum dots [J]. Nano Lett,2011,11:56-60.
[231] Lü C, YANG B. High refractive index organic–inorganic nanocomposites: design,synthesis and application [J]. Journal of Materials Chemistry,2009,19:2884.
[232] WANG Y, LI Y, YAN Y, et al. Luminescent carbon dots in a new magnesiumaluminophosphate zeolite [J]. Chem Commun,2013,49:9006-9008.
[233] WEN X, YU P, TOH Y-R, et al. Near-infrared enhanced carbon nanodots by thermallyassisted growth [J]. Applied Physics Letters,2012,101:163107.
[234] LI M, WU W, REN W, et al. Synthesis and upconversion luminescence of N-dopedgraphene quantum dots [J]. Applied Physics Letters,2012,101:103107.
[235] FAN L, ZHU M, LEE X, et al. Direct synthesis of graphene quantum dots by chemicalvapor deposition [J]. Particle&Particle Systems Characterization,2013,30:764-769.
[236] TANG L, JI R, LI X, et al. Size-Dependent structural and optical characteristics ofglucose-derived graphene quantum dots [J]. Particle&Particle Systems Characterization,2013,30:523-531.
[237] ZHANG X, XIE X, WANG H, et al. Enhanced photoresponsive ultrathin graphitic-phase C3N4nanosheets for bioimaging [J]. J Am Chem Soc,2013,135:18-21.
[238] LU Y, ZHANG L, LIN H. The Use of a Microreactor for Rapid Screening of theReaction Conditions and Investigation of the Photoluminescence Mechanism of Carbon Dots[J]. Chemistry-A European Journal,2014,10.1002/chem.201304358.
[239] YANG Y, WU D, HAN S, et al. Bottom-up fabrication of photoluminescent carbondots with uniform morphology via a soft-hard template approach [J]. Chem Commun,2013,49:4920-4922.
[240] ZONG J, ZHU Y, YANG X, et al. Synthesis of photoluminescent carbogenic dots usingmesoporous silica spheres as nanoreactors [J]. Chem Commun,2011,47:764-766.
[2] LI H, KANG Z, LIU Y, et al. Carbon nanodots: synthesis, properties and applications [J].Journal of Materials Chemistry,2012,22:24230-24253.
[3] WELSHER K, LIU Z, SHERLOCK S P, et al. A route to brightly fluorescent carbonnanotubes for near-infrared imaging in mice [J]. Nat Nanotechnol,2009,4:773-780.
[4] LI H, ZHANG Y, LUO Y, et al. Nano-C60: a novel, effective, fluorescent sensing platformfor biomolecular detection [J]. Small,2011,7:1562-1568.
[5] GAO M X, LIU C F, WU Z L, et al. A surfactant-assisted redox hydrothermal route toprepare highly photoluminescent carbon quantum dots with aggregation-induced emissionenhancement properties [J]. Chem Commun,2013,49:8015.
[6] YU S J, KANG M W, CHANG H C, et al. Bright fluorescent nanodiamonds: nophotobleaching and low cytotoxicity [J]. J Am Chem Soc,2005,127:17604-17605.
[7] CHANG I P, HWANG K C, CHIANG C S. Preparation of fluorescent magneticnanodiamonds and cellular imaging [J]. J Am Chem Soc,2008,130:15476-15481.
[8] MOCHALIN V N, SHENDEROVA O, HO D, et al. The properties and applications ofnanodiamonds [J]. Nat Nanotechnol,2012,7:11-23.
[9] GOKUS T, NAIR R R, BONETTI A, et al. Making graphene luminescent by oxygenplasma treatment [J]. ACS Nano,2009,3:3963-3968.
[10] DONG Y, SHAO J, CHEN C, et al. Blue luminescent graphene quantum dots andgraphene oxide prepared by tuning the carbonization degree of citric acid [J]. Carbon,2012,50:4738-4743.
[11] MEI Q, ZHANG Z. Photoluminescent graphene oxide ink to print sensors ontomicroporous membranes for versatile visualization bioassays [J]. Angew Chem Int Ed,2012,51:5602-5606.
[12] QIAN J, WANG D, CAI F H, et al. Observation of multiphoton-induced fluorescencefrom graphene oxide nanoparticles and applications in in vivo functional bioimaging [J].Angew Chem Int Ed,2012,51:10570-10575.
[13] WANG D, WANG L, DONG X, et al. Chemically tailoring graphene oxides intofluorescent nanosheets for Fe3+ion detection [J]. Carbon,2012,50:2147-2154.
[14] FENG L, YANG X, SHI X, et al. Polyethylene glycol and polyethylenimine dual-functionalized nano-graphene oxide for photothermally enhanced gene delivery [J]. Small,2013,9:1989-1997.
[15] GAN Z, XIONG S, WU X, et al. Mechanism of Photoluminescence from ChemicallyDerived Graphene Oxide: Role of Chemical Reduction [J]. Advanced Optical Materials,2013,1:926-932.
[16] LI J L, TANG B, YUAN B, et al. A review of optical imaging and therapy usingnanosized graphene and graphene oxide [J]. Biomaterials,2013,34:9519-9534.
[17] ZHANG X, WANG S, LIU M, et al. Size tunable fluorescent nano-graphite oxides:preparation and cell imaging applications [J]. Phys Chem Chem Phys,2013,15:19013-19018.
[18] CAO L, MEZIANI M J, SAHU S, et al. Photoluminescence properties of grapheneversus other carbon nanomaterials [J]. Acc Chem Res,2013,46:171-180.
[19] SHEN J, ZHU Y, YANG X, et al. Graphene quantum dots: emergent nanolights forbioimaging, sensors, catalysis and photovoltaic devices [J]. Chem Commun,2012,48:3686-3699.
[20] ZHANG Z, ZHANG J, CHEN N, et al. Graphene quantum dots: an emerging materialfor energy-related applications and beyond [J]. Energy&Environmental Science,2012,5:8869.
[21] LI L-S, YAN X. Colloidal Graphene Quantum Dots [J]. The Journal of PhysicalChemistry Letters,2010,1:2572-2576.
[22] LI L, WU G, YANG G, et al. Focusing on luminescent graphene quantum dots: currentstatus and future perspectives [J]. Nanoscale,2013,5:4015-4039.
[23] BACON M, BRADLEY S J, NANN T. Graphene Quantum Dots [J]. Particle&ParticleSystems Characterization,2014,31:415-428.
[24] LIN L, RONG M, LUO F, et al. Luminescent graphene quantum dots as new fluorescentmaterials for environmental and biological applications [J]. TrAC Trends in AnalyticalChemistry,2014,54:83-102.
[25] ZHOU X, GUO S, ZHANG J. Solution-processable graphene quantum dots [J].Chemphyschem,2013,14:2627-2640.
[26] XU X, RAY R, GU Y, et al. Electrophoretic analysis and purification of fluorescentsingle-walled carbon nanotube fragments [J]. J Am Chem Soc,2004,126:12736-12737.
[27] PONOMARENKO L A, SCHEDIN F, KATSNELSON M I, et al. Chaotic Dirac billiardin graphene quantum dots [J]. Science,2008,320:356-358.
[28] PAN D, ZHANG J, LI Z, et al. Hydrothermal route for cutting graphene sheets into blue-luminescent graphene quantum dots [J]. Adv Mater,2010,22:734-738.
[29] SHEN J, ZHU Y, CHEN C, et al. Facile preparation and upconversion luminescence ofgraphene quantum dots [J]. Chem Commun,2011,47:2580-2582.
[30] ZHAO J, CHEN G, ZHU L, et al. Graphene quantum dots-based platform for thefabrication of electrochemical biosensors [J]. Electrochemistry Communications,2011,13:31-33.
[31] LI Y, HU Y, ZHAO Y, et al. An electrochemical avenue to green-luminescent graphenequantum dots as potential electron-acceptors for photovoltaics [J]. Adv Mater,2011,23:776-780.
[32] ZHU S, ZHANG J, QIAO C, et al. Strongly green-photoluminescent graphene quantumdots for bioimaging applications [J]. Chem Commun,2011,47:6858-6860.
[33] LIU R, WU D, FENG X, et al. Bottom-up fabrication of photoluminescent graphenequantum dots with uniform morphology [J]. J Am Chem Soc,2011,133:15221-15223.
[34] LEE J, KIM K, PARK W I, et al. Uniform graphene quantum dots patterned from self-assembled silica nanodots [J]. Nano Lett,2012,12:6078-6083.
[35] PENG J, GAO W, GUPTA B K, et al. Graphene quantum dots derived from carbonfibers [J]. Nano Lett,2012,12:844-849.
[36] DONG Y, CHEN C, ZHENG X, et al. One-step and high yield simultaneous preparationof single-and multi-layer graphene quantum dots from CX-72carbon black [J]. Journal ofMaterials Chemistry,2012,22:8764.
[37] LIN L, ZHANG S. Creating high yield water soluble luminescent graphene quantum dotsvia exfoliating and disintegrating carbon nanotubes and graphite flakes [J]. Chem Commun,2012,48:10177-10179.
[38] LI L-L, JI J, FEI R, et al. A Facile Microwave Avenue to Electrochemiluminescent Two-Color Graphene Quantum Dots [J]. Advanced Functional Materials,2012,22:2971-2979.
[39] ZHOU X, ZHANG Y, WANG C, et al. Photo-Fenton reaction of graphene oxide: a newstrategy to prepare graphene quantum dots for DNA cleavage [J]. ACS Nano,2012,6:6592-6599.
[40] DONG Y, LI G, ZHOU N, et al. Graphene quantum dot as a green and facile sensor forfree chlorine in drinking water [J]. Anal Chem,2012,84:8378-8382.
[41] SUN Y P, ZHOU B, LIN Y, et al. Quantum-sized carbon dots for bright and colorfulphotoluminescence [J]. J Am Chem Soc,2006,128:7756-7757.
[42] CAO L, WANG X, MEZIANI M J, et al. Carbon dots for multiphoton bioimaging [J]. JAm Chem Soc,2007,129:11318-11319.
[43] LIU H, YE T, MAO C. Fluorescent carbon nanoparticles derived from candle soot [J].Angew Chem Int Ed,2007,46:6473-6475.
[44] ZHOU J, BOOKER C, LI R, et al. An electrochemical avenue to blue luminescentnanocrystals from multiwalled carbon nanotubes (MWCNTs)[J]. J Am Chem Soc,2007,129:744-745.
[45] ZHAO Q L, ZHANG Z L, HUANG B H, et al. Facile preparation of low cytotoxicityfluorescent carbon nanocrystals by electrooxidation of graphite [J]. Chem Commun,2008,44:5116-5118.
[46] LI H, HE X, KANG Z, et al. Water-soluble fluorescent carbon quantum dots andphotocatalyst design [J]. Angew Chem Int Ed,2010,49:4430-4434.
[47] HU S-L, NIU K-Y, SUN J, et al. One-step synthesis of fluorescent carbon nanoparticlesby laser irradiation [J]. Journal of Materials Chemistry,2009,19:484.
[48] LIU R, WU D, LIU S, et al. An aqueous route to multicolor photoluminescent carbondots using silica spheres as carriers [J]. Angew Chem Int Ed,2009,48:4598-4601.
[49] RAY S C, SAHA A, JANA N R, et al. Fluorescent Carbon Nanoparticles: Synthesis,Characterization, and Bioimaging Application [J]. Journal Of Physical Chemistry C,2009,113:18546-18551.
[50] QIAO Z A, WANG Y, GAO Y, et al. Commercially activated carbon as the source forproducing multicolor photoluminescent carbon dots by chemical oxidation [J]. ChemCommun,2010,46:8812-8814.
[51] E Y F, BAI L L, FAN L Z, et al. Electrochemically generated fluorescent fullerene[60]nanoparticles as a new and viable bioimaging platform [J]. Journal of Materials Chemistry,2011,21:819-823.
[52] WANG F, XIE Z, ZHANG H, et al. Highly Luminescent Organosilane-FunctionalizedCarbon Dots [J]. Advanced Functional Materials,2011,21:1027-1031.
[53] YANG Z C, WANG M, YONG A M, et al. Intrinsically fluorescent carbon dots withtunable emission derived from hydrothermal treatment of glucose in the presence ofmonopotassium phosphate [J]. Chem Commun,2011,47:11615-11617.
[54] CHANDRA S, MITRA S, LAHA D, et al. Fabrication of multi-structure nanocarbonsfrom carbon xerogel: a unique scaffold towards bio-imaging [J]. Chem Commun,2011,47:8587-8589.
[55] LIU C, ZHANG P, ZHAI X, et al. Nano-carrier for gene delivery and bioimaging basedon carbon dots with PEI-passivation enhanced fluorescence [J]. Biomaterials,2012,33:3604-3613.
[56] HSU P C, CHANG H T. Synthesis of high-quality carbon nanodots from hydrophiliccompounds: role of functional groups [J]. Chem Commun,2012,48:3984-3986.
[57] SONG Y C, SHI W, CHEN W, et al. Fluorescent carbon nanodots conjugated with folicacid for distinguishing folate-receptor-positive cancer cells from normal cells [J]. Journal ofMaterials Chemistry,2012,22:12568-12573.
[58] LAI C W, HSIAO Y H, PENG Y K, et al. Facile synthesis of highly emissive carbondots from pyrolysis of glycerol; gram scale production of carbon dots/SiO2for cell imagingand drug release [J]. Journal of Materials Chemistry,2012,22:14403-14409.
[59] ZHAI X, ZHANG P, LIU C, et al. Highly luminescent carbon nanodots by microwave-assisted pyrolysis [J]. Chem Commun,2012,48:7955-7957.
[60] ZHANG Z, HAO J H, ZHANG J, et al. Protein as the source for synthesizing fluorescentcarbon dots by a one-pot hydrothermal route [J]. RSC Advances,2012,2:8599-8601.
[61] CHEN B, LI F, LI S, et al. Large scale synthesis of photoluminescent carbon nanodotsand their application for bioimaging [J]. Nanoscale,2013,5:1967-1971.
[62] ZHU S, MENG Q, WANG L, et al. Highly photoluminescent carbon dots for multicolorpatterning, sensors, and bioimaging [J]. Angew Chem Int Ed,2013,52:3953-3957.
[63] BHUNIA S K, SAHA A, MAITY A R, et al. Carbon nanoparticle-based fluorescentbioimaging probes [J]. Sci Rep,2013,3:1473.
[64] SAHU S, BEHERA B, MAITI T K, et al. Simple one-step synthesis of highlyluminescent carbon dots from orange juice: application as excellent bio-imaging agents [J].Chem Commun,2012,48:8835-8837.
[65] SUN D, BAN R, ZHANG P H, et al. Hair fiber as a precursor for synthesizing of sulfur-and nitrogen-co-doped carbon dots with tunable luminescence properties [J]. Carbon,2013,64:424-434.
[66] WANG W, LI Y M, CHENG L, et al. Water-soluble and phosphorus-containing carbondots with strong green fluorescence for cell labeling [J]. Journal of Materials Chemistry B,2014,2:46-48.
[67] HUANG H, XU Y, TANG C-J, et al. Facile and green synthesis of photoluminescentcarbon nanoparticles for cellular imaging [J]. New Journal of Chemistry,2014,38:784.
[68] WU C, CHIU D T. Highly fluorescent semiconducting polymer dots for biology andmedicine [J]. Angew Chem Int Ed,2013,52:3086-3109.
[69] ZHANG X, YU J, RONG Y, et al. High-intensity near-IR fluorescence insemiconducting polymer dots achieved by cascade FRET strategy [J]. Chemical Science,2013,4:2143.
[70] LIU S, TIAN J, WANG L, et al. Hydrothermal treatment of grass: a low-cost, greenroute to nitrogen-doped, carbon-rich, photoluminescent polymer nanodots as an effectivefluorescent sensing platform for label-free detection of Cu(II) ions [J]. Adv Mater,2012,24:2037-2041.
[71] ZHU S, ZHANG J, WANG L, et al. A general route to make non-conjugated linearpolymers luminescent [J]. Chem Commun,2012,48:10889-10891.
[72] LAI T, ZHENG E, CHEN L, et al. Hybrid carbon source for producing nitrogen-dopedpolymer nanodots: one-pot hydrothermal synthesis, fluorescence enhancement and highlyselective detection of Fe(III)[J]. Nanoscale,2013,5:8015-8021.
[73] FAN R-J, SUN Q, ZHANG L, et al. Photoluminescent carbon dots directly derived frompolyethylene glycol and their application for cellular imaging [J]. Carbon,2014,10.1016/j.carbon.2014.01.016.
[74] GU J, WANG W, ZHANG Q, et al. Synthesis of fluorescent carbon nanoparticles frompolyacrylamide for fast cellular endocytosis [J]. RSC Advances,2013,3:15589.
[75] LI W, ZHANG Z, KONG B, et al. Simple and green synthesis of nitrogen-dopedphotoluminescent carbonaceous nanospheres for bioimaging [J]. Angew Chem Int Ed,2013,52:8151-8155.
[76] YANG Y, CUI J, ZHENG M, et al. One-step synthesis of amino-functionalizedfluorescent carbon nanoparticles by hydrothermal carbonization of chitosan [J]. ChemCommun,2012,48:380-382.
[77] SUN Y, CAO W, LI S, et al. Ultrabright and multicolorful fluorescence of amphiphilicpolyethyleneimine polymer dots for efficiently combined imaging and therapy [J]. Sci Rep,2013,3:3036.
[78] DING D, GOH C C, FENG G, et al. Ultrabright organic dots with aggregation-inducedemission characteristics for real-time two-photon intravital vasculature imaging [J]. AdvMater,2013,10.1002/adma.201301938.
[79] LI K, QIN W, DING D, et al. Photostable fluorescent organic dots with aggregation-induced emission (AIE dots) for noninvasive long-term cell tracing [J]. Sci Rep,2013,3:1150.
[80] ZHANG X, WANG S, XU L, et al. Biocompatible polydopamine fluorescent organicnanoparticles: facile preparation and cell imaging [J]. Nanoscale,2012,4:5581-5584.
[81] QIAO Z A, HUO Q, CHI M, et al. A "ship-in-a-bottle" approach to synthesis of polymerdots@silica or polymer dots@carbon core-shell nanospheres [J]. Adv Mater,2012,24:6017-6021.
[82] GUO C X, XIE J, WANG B, et al. A new class of fluorescent-dots: long luminescentlifetime bio-dots self-assembled from DNA at low temperatures [J]. Sci Rep,2013,3:2957.
[83] GAN Z X, XIONG S J, WU X L, et al. Mechanism of Photoluminescence fromChemically Derived Graphene Oxide: Role of Chemical Reduction [J]. Advanced OpticalMaterials,2013,1:926-932.
[84] BAO L, ZHANG Z L, TIAN Z Q, et al. Electrochemical tuning of luminescent carbonnanodots: from preparation to luminescence mechanism [J]. Adv Mater,2011,23:5801-5806.
[85] PAN D, ZHANG J, LI Z, et al. Observation of pH-, solvent-, spin-, and excitation-dependent blue photoluminescence from carbon nanoparticles [J]. Chem Commun,2010,46:3681-3683.
[86] ZHANG Y, GONCALVES H, DA SILVA J C, et al. Metal-enhanced photoluminescencefrom carbon nanodots [J]. Chem Commun,2011,47:5313-5315.
[87] YU P, WEN X, TOH Y-R, et al. Temperature-Dependent Fluorescence in Carbon Dots[J]. The Journal of Physical Chemistry C,2012,116:25552-25557.
[88] WANG L, ZHU S-J, WANG H-Y, et al. Unraveling bright molecule-like state and darkintrinsic state in green-fluorescence graphene quantum dots via ultrafast spectroscopy [J].Advanced Optical Materials,2013,1:264-271.
[89] EDA G, LIN Y Y, MATTEVI C, et al. Blue photoluminescence from chemically derivedgraphene oxide [J]. Adv Mater,2010,22:505-509.
[90] SHANG J, MA L, LI J, et al. The origin of fluorescence from graphene oxide [J]. SciRep,2012,2:792.
[91] WANG L, WANG H Y, WANG Y, et al. Direct observation of quantum-confinedgraphene-like states and novel hybrid states in graphene oxide by transient spectroscopy [J].Adv Mater,2013,25:6539-6545.
[92] KIM S, HWANG S W, KIM M K, et al. Anomalous behaviors of visible luminescencefrom graphene quantum dots: interplay between size and shape [J]. ACS Nano,2012,6:8203-8208.
[93] XU Q, ZHOU Q, HUA Z, et al. Single-particle spectroscopic measurements offluorescent graphene quantum dots [J]. ACS Nano,2013,7:10654-10661.
[94] TETSUKA H, ASAHI R, NAGOYA A, et al. Optically tunable amino-functionalizedgraphene quantum dots [J]. Adv Mater,2012,24:5333-5338.
[95] JIN S H, KIM DA H, JUN G H, et al. Tuning the photoluminescence of graphenequantum dots through the charge transfer effect of functional groups [J]. ACS Nano,2013,7:1239-1245.
[96] ZHU S, ZHANG J, TANG S, et al. Surface chemistry routes to modulate thephotoluminescence of graphene quantum dots: from fuorescence mechanism to up-conversionbioimaging applications [J]. Advanced Functional Materials,2012,22:4732-4740.
[97] ZHENG H, WANG Q, LONG Y, et al. Enhancing the luminescence of carbon dots witha reduction pathway [J]. Chem Commun,2011,47:10650-10652.
[98] LIU F, JANG M H, HA H D, et al. Facile synthetic method for pristine graphenequantum dots and graphene oxide quantum dots: origin of blue and green luminescence [J].Adv Mater,2013,25:3657-3662.
[99] LINGAM K, PODILA R, QIAN H, et al. Evidence for edge-state photoluminescence ingraphene quantum dots [J]. Advanced Functional Materials,2013,23:5062-5065.
[100] WANG X, CAO L, LU F, et al. Photoinduced electron transfers with carbon dots [J].Chem Commun,2009,10.1039/b906252a:3774-3776.
[101] YANG S T, WANG X, WANG H, et al. Carbon dots as nontoxic and high-performancefluorescence imaging agents [J]. J Phys Chem C Nanomater Interfaces,2009,113:18110-18114.
[102] WEN X, YU P, TOH Y-R, et al. Intrinsic and extrinsic fluorescence in carbon nanodots:ultrafast time-resolved fluorescence and carrier dynamics [J]. Advanced Optical Materials,2013,1:173-178.
[103] BOURLINOS A B, STASSINOPOULOS A, ANGLOS D, et al. Surface functionalizedcarbogenic quantum dots [J]. Small,2008,4:455-458.
[104] VINCI J C, FERRER I M, SEEDHOUSE S J, et al. Hidden properties of carbon dotsrevealed after HPLC fractionation [J]. The Journal of Physical Chemistry Letters,2013,4:239-243.
[105] TAN D, ZHOU S, SHIMOTSUMA Y, et al. Effect of UV irradiation onphotoluminescence of carbon dots [J]. Optical Materials Express,2014,4:213.
[106] CHEN S, LIU J W, CHEN M L, et al. Unusual emission transformation of graphenequantum dots induced by self-assembled aggregation [J]. Chem Commun,2012,48:7637-7639.
[107] YANG F, ZHAO M, ZHENG B, et al. Influence of pH on the fluorescence properties ofgraphene quantum dots using ozonation pre-oxide hydrothermal synthesis [J]. Journal ofMaterials Chemistry,2012,22:25471.
[108] WANG L, ZHU S J, WANG H Y, et al. Common origin of green luminescence incarbon nanodots and graphene quantum dots [J]. ACS Nano,2014,8:2541-2547.
[109] DAS S K, LIU Y, YEOM S, et al. Single-particle fluorescence intensity fluctuations ofcarbon nanodots [J]. Nano Lett,2014,14:620-625.
[110] BOURLINOS A B, STASSINOPOULOS A, ANGLOS D, et al. PhotoluminescentCarbogenic Dots [J]. Chemistry of Materials,2008,20:4539-4541.
[111] BOURLINOS A B, GEORGAKILAS V, ZBORIL R, et al. Pyrolytic formation andphotoluminescence properties of a new layered carbonaceous material with graphite oxide-mimicking characteristics [J]. Carbon,2009,47:519-526.
[112] ZHENG L, CHI Y, DONG Y, et al. Electrochemiluminescence of water-soluble carbonnanocrystals released electrochemically from graphite [J]. J Am Chem Soc,2009,131:4564-4565.
[113] ZHOU J, ZHOU X, LI R, et al. Electronic structure and luminescence center of blueluminescent carbon nanocrystals [J]. Chemical Physics Letters,2009,474:320-324.
[114] ZHU H, WANG X, LI Y, et al. Microwave synthesis of fluorescent carbonnanoparticles with electrochemiluminescence properties [J]. Chem Commun,2009,10.1039/b907612c:5118-5120.
[115] MAO X J, ZHENG H Z, LONG Y J, et al. Study on the fluorescence characteristics ofcarbon dots [J]. Spectrochim Acta A Mol Biomol Spectrosc,2010,75:553-557.
[116] WANG F, XIE Z, ZHANG H, et al. Highly Luminescent Organosilane-FunctionalizedCarbon Dots [J]. Advanced Functional Materials,2011,21:1027-1031.
[117] HOLA K, BOURLINOS A B, KOZAK O, et al. Photoluminescence effects of graphiticcore size and surface functional groups in carbon dots: COO induced red-shift emission [J].Carbon,2014,70:279-286.
[118] KRYSMANN M J, KELARAKIS A, DALLAS P, et al. Formation mechanism ofcarbogenic nanoparticles with dual photoluminescence emission [J]. J Am Chem Soc,2012,134:747-750.
[119] LIN Z, XUE W, CHEN H, et al. Peroxynitrous-acid-induced chemiluminescence offluorescent carbon dots for nitrite sensing [J]. Anal Chem,2011,83:8245-8251.
[120] LI C, ZHU Y, ZHANG X, et al. Metal-enhanced fluorescence of carbon dots adsorbedAg@SiO2core-shell nanoparticles [J]. RSC Advances,2012,2:1765.
[121] DONG Y, PANG H, YANG H B, et al. Carbon-based dots co-doped with nitrogen andsulfur for high quantum yield and excitation-independent emission [J]. Angew Chem Int Ed,2013,52:7800-7804.
[122] LI F, LIU C, YANG J, et al. Mg/N double doping strategy to fabricate extremely highluminescent carbon dots for bioimaging [J]. RSC Advances,2014,4:3201.
[123] RAN X, SUN H, PU F, et al. Ag nanoparticle-decorated graphene quantum dots forlabel-free, rapid and sensitive detection of Ag+and biothiols [J]. Chem Commun,2013,49:1079-1081.
[124] QU Z B, ZHOU X, GU L, et al. Boronic acid functionalized graphene quantum dots asa fluorescent probe for selective and sensitive glucose determination in microdialysate [J].Chem Commun,2013,49:9830-9832.
[125] CHANDRA S, PATRA P, PATHAN S H, et al. Luminescent S-doped carbon dots: anemergent architecture for multimodal applications [J]. Journal of Materials Chemistry B,2013,1:2375.
[126] KWON W, LIM J, LEE J, et al. Sulfur-incorporated carbon quantum dots with a stronglong-wavelength absorption band [J]. Journal of Materials Chemistry C,2013,1:2002.
[127] QU D, ZHENG M, DU P, et al. Highly luminescent S, N co-doped graphene quantumdots with broad visible absorption bands for visible light photocatalysts [J]. Nanoscale,2013,5:12272-12277.
[128] LIU S, YU B, ZHANG T. Nitrogen-doped carbon nanodots as a reducing agent tosynthesize Ag nanoparticles for non-enzymatic hydrogen peroxide detection [J]. RSCAdvances,2014,4:544.
[129] NIU J, GAO H, WANG L, et al. Facile synthesis and optical properties of nitrogen-doped carbon dots [J]. New Journal of Chemistry,2014,38:1522-1527.
[130] YANG Z, XU M, LIU Y, et al. Nitrogen-doped, carbon-rich, highly photoluminescentcarbon dots from ammonium citrate [J]. Nanoscale,2014,6:1890-1895.
[131] LI Y, ZHAO Y, CHENG H, et al. Nitrogen-doped graphene quantum dots with oxygen-rich functional groups [J]. J Am Chem Soc,2012,134:15-18.
[132] HU C, LIU Y, YANG Y, et al. One-step preparation of nitrogen-doped graphenequantum dots from oxidized debris of graphene oxide [J]. Journal of Materials Chemistry B,2013,1:39.
[133] GUPTA V, CHAUDHARY N, SRIVASTAVA R, et al. Luminscent graphene quantumdots for organic photovoltaic devices [J]. J Am Chem Soc,2011,133:9960-9963.
[134] DUTTA M, SARKAR S, GHOSH T, et al. ZnO/graphene quantum dot solid-state solarcell [J]. The Journal of Physical Chemistry C,2012,116:20127-20131.
[135] CHEN L, GUO C X, ZHANG Q, et al. Graphene quantum-dot-doped polypyrrolecounter electrode for high-performance dye-sensitized solar cells [J]. ACS Appl MaterInterfaces,2013,5:2047-2052.
[136] MIRTCHEV P, HENDERSON E J, SOHEILNIA N, et al. Solution phase synthesis ofcarbon quantum dots as sensitizers for nanocrystalline TiO2solar cells [J]. Journal ofMaterials Chemistry,2012,22:1265.
[137] TANG L, JI R, CAO X, et al. Deep ultraviolet photoluminescence of water-soluble self-passivated graphene quantum dots [J]. ACS Nano,2012,6:5102-5110.
[138] KWON W, DO S, LEE J, et al. Freestanding Luminescent Films of Nitrogen-RichCarbon Nanodots toward Large-Scale Phosphor-Based White-Light-Emitting Devices [J].Chemistry of Materials,2013,25:1893-1899.
[139] WANG F, CHEN Y H, LIU C Y, et al. White light-emitting devices based on carbondots' electroluminescence [J]. Chem Commun,2011,47:3502-3504.
[140] ZHANG X, ZHANG Y, WANG Y, et al. Color-switchable electroluminescence ofcarbon dot light-emitting diodes [J]. ACS Nano,2013,7:11234-11241.
[141] SHEN J, ZHU Y, YANG X, et al. One-pot hydrothermal synthesis of graphenequantum dots surface-passivated by polyethylene glycol and their photoelectric conversionunder near-infrared light [J]. New Journal of Chemistry,2012,36:97.
[142] CHOI H, KO S-J, CHOI Y, et al. Versatile surface plasmon resonance of carbon-dot-supported silver nanoparticles in polymer optoelectronic devices [J]. Nature Photonics,2013,7:732-738.
[143] SON D I, KWON B W, PARK D H, et al. Emissive ZnO-graphene quantum dots forwhite-light-emitting diodes [J]. Nat Nanotechnol,2012,7:465-471.
[144] CHENG S H, WENG T M, LU M L, et al. All carbon-based photodetectors: an eminentintegration of graphite quantum dots and two dimensional graphene [J]. Sci Rep,2013,3:2694.
[145] KOU L, LI F, CHEN W, et al. Synthesis of blue light-emitting graphene quantum dotsand their application in flexible nonvolatile memory [J]. Organic Electronics,2013,14:1447-1451.
[146] LEE E, RYU J, JANG J. Fabrication of graphene quantum dots via size-selectiveprecipitation and their application in upconversion-based DSSCs [J]. Chem Commun,2013,49:9995-9997.
[147] LIU W-W, FENG Y-Q, YAN X-B, et al. Superior Micro-Supercapacitors Based onGraphene Quantum Dots [J]. Advanced Functional Materials,2013,23:4111-4122.
[148] LIU W, YAN X, CHEN J, et al. Novel and high-performance asymmetric micro-supercapacitors based on graphene quantum dots and polyaniline nanofibers [J]. Nanoscale,2013,5:6053-6062.
[149] ZHUO S, SHAO M, LEE S T. Upconversion and downconversion fluorescent graphenequantum dots: ultrasonic preparation and photocatalysis [J]. ACS Nano,2012,6:1059-1064.
[150] ZHENG M, XIE Z, QU D, et al. On-off-on fluorescent carbon dot nanosensor forrecognition of chromium(VI) and ascorbic acid based on the inner filter effect [J]. ACS ApplMater Interfaces,2013,5:13242-13247.
[151] LIN Z, XUE W, CHEN H, et al. Classical oxidant induced chemiluminescence offluorescent carbon dots [J]. Chem Commun,2012,48:1051-1053.
[152] LU W, QIN X, LIU S, et al. Economical, green synthesis of fluorescent carbonnanoparticles and their use as probes for sensitive and selective detection of mercury(II) ions[J]. Anal Chem,2012,84:5351-5357.
[153] ZHAO H X, LIU L Q, LIU Z D, et al. Highly selective detection of phosphate in verycomplicated matrixes with an off-on fluorescent probe of europium-adjusted carbon dots [J].Chem Commun,2011,47:2604-2606.
[154] WEI W, XU C, REN J, et al. Sensing metal ions with ion selectivity of a crown etherand fluorescence resonance energy transfer between carbon dots and graphene [J]. ChemCommun,2012,48:1284-1286.
[155] ZHU A, DING C, TIAN Y. A two-photon ratiometric fluorescence probe for cupricions in live cells and tissues [J]. Sci Rep,2013,3:2933.
[156] KONG B, ZHU A, DING C, et al. Carbon dot-based inorganic-organic nanosystem fortwo-photon imaging and biosensing of pH variation in living cells and tissues [J]. Adv Mater,2012,24:5844-5848.
[157] ZHU A, QU Q, SHAO X, et al. Carbon-dot-based dual-emission nanohybrid produces aratiometric fluorescent sensor for in vivo imaging of cellular copper ions [J]. Angew ChemInt Ed,2012,51:7185-7189.
[158] SREEPRASAD T S, RODRIGUEZ A A, COLSTON J, et al. Electron-tunnelingmodulation in percolating network of graphene quantum dots: fabrication, phenomenologicalunderstanding, and humidity/pressure sensing applications [J]. Nano Lett,2013,13:1757-1763.
[159] ZHAO H, CHANG Y, LIU M, et al. A universal immunosensing strategy based onregulation of the interaction between graphene and graphene quantum dots [J]. ChemCommun,2013,49:234-236.
[160] BAI J M, ZHANG L, LIANG R P, et al. Graphene quantum dots combined witheuropium ions as photoluminescent probes for phosphate sensing [J]. Chemistry,2013,19:3822-3826.
[161] HUANG H, LIAO L, XU X, et al. The electron-transfer based interaction betweentransition metal ions and photoluminescent graphene quantum dots (GQDs): a platform formetal ion sensing [J]. Talanta,2013,117:152-157.
[162] LIU J J, ZHANG X L, CONG Z X, et al. Glutathione-functionalized graphene quantumdots as selective fluorescent probes for phosphate-containing metabolites [J]. Nanoscale,2013,5:1810-1815.
[163] LU J, YAN M, GE L, et al. Electrochemiluminescence of blue-luminescent graphenequantum dots and its application in ultrasensitive aptasensor for adenosine triphosphatedetection [J]. Biosens Bioelectron,2013,47:271-277.
[164] SUN H, GAO N, WU L, et al. Highly photoluminescent amino-functionalized graphenequantum dots used for sensing copper ions [J]. Chemistry,2013,19:13362-13368.
[165] WANG X, CHEN L, SU X, et al. Electrochemical immunosensor with graphenequantum dots and apoferritin-encapsulated Cu nanoparticles double-assisted signalamplification for detection of avian leukosis virus subgroup J [J]. Biosens Bioelectron,2013,47:171-177.
[166] ZHOU L, GENG J, LIU B. Graphene quantum dots from polycyclic aromatichydrocarbon for bioimaging and sensing of Fe3+and hydrogen peroxide [J]. Particle&Particle Systems Characterization,2013,30:1086-1092.
[167] ANANTHANARAYANAN A, WANG X, ROUTH P, et al. Facile synthesis ofgraphene quantum dots from3D graphene and their application for Fe3+sensing [J]. AdvancedFunctional Materials,2014,24:3021-3026.
[168] WANG F, GU Z, LEI W, et al. Graphene quantum dots as a fluorescent sensingplatform for highly efficient detection of copper(II)ions [J]. Sensors and Actuators B:Chemical,2014,190:516-522.
[169] WU Z, LI W, CHEN J, et al. A graphene quantum dot-based method for the highlysensitive and selective fluorescence turn on detection of biothiols [J]. Talanta,2014,119:538-543.
[170] LIU J, LI J, JIANG Y, et al. Combination of pi-pi stacking and electrostatic repulsionbetween carboxylic carbon nanoparticles and fluorescent oligonucleotides for rapid andsensitive detection of thrombin [J]. Chem Commun,2011,47:11321-11323.
[171] YIN B, DENG J, PENG X, et al. Green synthesis of carbon dots with down-and up-conversion fluorescent properties for sensitive detection of hypochlorite with a dual-readoutassay [J]. Analyst,2013,138:6551-6557.
[172] QIN X, LU W, ASIRI A M, et al. Green, low-cost synthesis of photoluminescentcarbon dots by hydrothermal treatment of willow bark and their application as an effectivephotocatalyst for fabricating Au nanoparticles–reduced graphene oxide nanocomposites forglucose detection [J]. Catalysis Science&Technology,2013,3:1027.
[173] WANG Q, LIU X, ZHANG L, et al. Microwave-assisted synthesis of carbon nanodotsthrough an eggshell membrane and their fluorescent application [J]. Analyst,2012,137:5392-5397.
[174] HUANG H, LV J J, ZHOU D L, et al. One-pot green synthesis of nitrogen-dopedcarbon nanoparticles as fluorescent probes for mercury ions [J]. RSC Advances,2013,3:21691-21696.
[175] JIA X, LI J, WANG E. One-pot green synthesis of optically pH-sensitive carbon dotswith upconversion luminescence [J]. Nanoscale,2012,4:5572-5575.
[176] QU S, CHEN H, ZHENG X, et al. Ratiometric fluorescent nanosensor based on watersoluble carbon nanodots with multiple sensing capacities [J]. Nanoscale,2013,5:5514-5518.
[177] FAN L, HU Y, WANG X, et al. Fluorescence resonance energy transfer quenching atthe surface of graphene quantum dots for ultrasensitive detection of TNT [J]. Talanta,2012,101:192-197.
[178] GUO Y, WANG Z, SHAO H, et al. Hydrothermal synthesis of highly fluorescentcarbon nanoparticles from sodium citrate and their use for the detection of mercury ions [J].Carbon,2013,52:583-589.
[179] ZHANG Y-L, WANG L, ZHANG H-C, et al. Graphitic carbon quantum dots as afluorescent sensing platform for highly efficient detection of Fe3+ions [J]. RSC Advances,2013,3:3733.
[180] ZHANG C, LIU Y, XIONG X Q, et al. Three-dimensional nanographene based ontriptycene: synthesis and its application in fluorescence imaging [J]. Org Lett,2012,14:5912-5915.
[181] ZHANG M, BAI L, SHANG W, et al. Facile synthesis of water-soluble, highlyfluorescent graphene quantum dots as a robust biological label for stem cells [J]. Journal ofMaterials Chemistry,2012,22:7461.
[182] ABDULLAH AL N, LEE J E, IN I, et al. Target delivery and cell imaging usinghyaluronic acid-functionalized graphene quantum dots [J]. Mol Pharm,2013,10:3736-3744.
[183] CHEN X, ZHOU X, HAN T, et al. Stabilization and induction of oligonucleotide i-motif structure via graphene quantum dots [J]. ACS Nano,2013,7:531-537.
[184] DENG L, LIU L, ZHU C, et al. Hybrid gold nanocube@silica@graphene-quantum-dotsuperstructures: synthesis and specific cell surface protein imaging applications [J]. ChemCommun,2013,49:2503-2505.
[185] WU C, WANG C, HAN T, et al. Insight into the cellular internalization andcytotoxicity of graphene quantum dots [J]. Adv Healthc Mater,2013,2:1613-1619.
[186] WU X, TIAN F, WANG W, et al. Fabrication of highly fluorescent graphene quantumdots using L-glutamic acid for imaging and sensing [J]. J Mater Chem C Mater Opt ElectronDevices,2013,1:4676-4684.
[187] YANG K, FENG L, SHI X, et al. Nano-graphene in biomedicine: theranosticapplications [J]. Chem Soc Rev,2013,42:530-547.
[188] ZHENG X T, THAN A, ANANTHANARAYA A, et al. Graphene quantum dots asuniversal fluorophores and their use in revealing regulated trafficking of insulin receptors inadipocytes [J]. ACS Nano,2013,7:6278-6286.
[189] TAO H, YANG K, MA Z, et al. In Vivo NIR Fluorescence imaging, biodistribution,and toxicology of photoluminescent carbon dots produced from carbon nanotubes andgraphite [J]. Small,2011,10.1002/smll.201101706.
[190] KUMAR V, TOFFOLI G, RIZZOLIO F. Fluorescent carbon nanoparticles in medicinefor cancer therapy [J]. ACS Medicinal Chemistry Letters,2013,4:1012-1013.
[191] WANG W, LI Y, CHENG L, et al. Water-soluble and phosphorus-containing carbondots with strong green fluorescence for cell labeling [J]. Journal of Materials Chemistry B,2014,2:46.
[192] YAN F, ZOU Y, WANG M, et al. Highly photoluminescent carbon dots-basedfluorescent chemosensors for sensitive and selective detection of mercury ions andapplication of imaging in living cells [J]. Sensors and Actuators B: Chemical,2014,192:488-495.
[193] LIU Y, WU P. Graphene quantum dot hybrids as efficient metal-free electrocatalyst forthe oxygen reduction reaction [J]. ACS Appl Mater Interfaces,2013,5:3362-3369.
[194] TANG J, KONG B, WU H, et al. Carbon nanodots featuring efficient FRET for real-time monitoring of drug delivery and two-photon imaging [J]. Adv Mater,2013,25:6569-6574.
[195] HUANG X, ZHANG F, ZHU L, et al. Effect of injection routes on the biodistribution,clearance, and tumor uptake of carbon dots [J]. ACS Nano,2013,7:5684-5693.
[196] WU L, LUDERER M, YANG X, et al. Surface passivation of carbon nanoparticles withbranched macromolecules influences near infrared bioimaging [J]. Theranostics,2013,3:677-686.
[197] LUO P G, SAHU S, YANG S-T, et al. Carbon “quantum” dots for optical bioimaging[J]. Journal of Materials Chemistry B,2013,1:2116.
[198] XU H, LI Q, WANG L, et al. Nanoscale optical probes for cellular imaging [J]. ChemSoc Rev,2014,10.1039/c3cs60309a.
[199] CHEN M, YIN M. Design and development of fluorescent nanostructures forbioimaging [J]. Progress in Polymer Science,2014,39:365-395.
[200] XIE Z, WANG F, LIU C Y. Organic-inorganic hybrid functional carbon dot gel glasses[J]. Adv Mater,2012,24:1716-1721.
[201] CHENG H, ZHAO Y, FAN Y, et al. Graphene-quantum-dot assembled nanotubes: anew platform for efficient Raman enhancement [J]. ACS Nano,2012,6:2237-2244.
[202] DING Y, CHENG H, ZHOU C, et al. Functional microspheres of graphene quantumdots [J]. Nanotechnology,2012,23:255605.
[203] ZHANG G, ZHANG H, ZHANG X, et al. Embedding graphene nanoparticles intopoly(N,N′-dimethylacrylamine) to prepare transparent nanocomposite films with highrefractive index [J]. Journal of Materials Chemistry,2012,22:21218.
[204] QU S, WANG X, LU Q, et al. A biocompatible fluorescent ink based on water-solubleluminescent carbon nanodots [J]. Angew Chem Int Ed,2012,51:12215-12218.
[205] WANG X, CAO L, YANG S T, et al. Bandgap-like strong fluorescence infunctionalized carbon nanoparticles [J]. Angew Chem Int Ed,2010,49:5310-5314.
[206] ZHU S, ZHANG J, LIU X, et al. Graphene quantum dots with controllable surfaceoxidation, tunable fluorescence and up-conversion emission [J]. RSC Advances,2012,2:2717.
[207] LIU Q, GUO B, RAO Z, et al. Strong two-photon-induced fluorescence fromphotostable, biocompatible nitrogen-doped graphene quantum dots for cellular and deep-tissue imaging [J]. Nano Lett,2013,13:2436-2441.
[208] SUN Y, WANG S, LI C, et al. Large scale preparation of graphene quantum dots fromgraphite with tunable fluorescence properties [J]. Phys Chem Chem Phys,2013,15:9907-9913.
[209] YE R, XIANG C, LIN J, et al. Coal as an abundant source of graphene quantum dots [J].Nat Commun,2013,4:2943.
[210] GAN Z, WU X, ZHOU G, et al. Is There real upconversion photoluminescence fromgraphene quantum dots?[J]. Advanced Optical Materials,2013,1:554-558.
[211] LUO P, JI Z, LI C, et al. Aryl-modified graphene quantum dots with enhancedphotoluminescence and improved pH tolerance [J]. Nanoscale,2013,5:7361-7367.
[212] LI X, LAU S P, TANG L, et al. Multicolour light emission from chlorine-dopedgraphene quantum dots [J]. Journal of Materials Chemistry C,2013,1:7308.
[213] XUE Q, HUANG H, WANG L, et al. Nearly monodisperse graphene quantum dotsfabricated by amine-assisted cutting and ultrafiltration [J]. Nanoscale,2013,5:12098-12103.
[214] SUN H, WU L, GAO N, et al. Improvement of photoluminescence of graphenequantum dots with a biocompatible photochemical reduction pathway and its bioimagingapplication [J]. ACS Appl Mater Interfaces,2013,5:1174-1179.
[215] QIAN Z, MA J, SHAN X, et al. Surface functionalization of graphene quantum dotswith small organic molecules from photoluminescence modulation to bioimaging applications:an experimental and theoretical investigation [J]. RSC Advances,2013,3:14571.
[216] PAN D, GUO L, ZHANG J, et al. Cutting sp2clusters in graphene sheets into colloidalgraphene quantum dots with strong green fluorescence [J]. Journal of Materials Chemistry,2012,22:3314.
[217] JIANG F, CHEN D, LI R, et al. Eco-friendly synthesis of size-controllable amine-functionalized graphene quantum dots with antimycoplasma properties [J]. Nanoscale,2013,5:1137-1142.
[218] SONG Y, ZHU S, XIANG S, et al. Investigation into the fluorescence quenchingbehaviors and applications of carbon dots [J]. Nanoscale,2014,10.1039/c4nr00029c.
[219] QIAO Z-A, WANG Y, GAO Y, et al. Commercially activated carbon as the source forproducing multicolor photoluminescent carbon dots by chemical oxidation [J]. ChemCommun,2010,46:8812-8814.
[220] IYER V S, WEHMEIER M, BRAND J D, et al. From Hexa-peri-hexabenzocoroneneto“Superacenes”[J]. Angew Chem Int Ed,1997,36:1604-1607.
[221] ITO S, WEHMEIER M, BRAND J D, et al. Synthesis and Self-Assembly ofFunctionalized Hexa-peri-hexabenzocoronenes [J]. Chemistry,2000,6:4327-4342.
[222] TOMOVIC Z, WATSON M D, MULLEN K. Superphenalene-based columnar liquidcrystals [J]. Angew Chem Int Ed,2004,43:755-758.
[223] SAMOR P, SEVERIN N, SIMPSON C D, et al. Epitaxial composite layers of electrondonors and acceptors from very large polycyclic aromatic hydrocarbons [J]. J Am Chem Soc,2002,124:9454-9457.
[224] SIMPSON C D, BRAND J D, BERRESHEIM A J, et al. Synthesis of a Giant222Carbon Graphite Sheet [J]. Chemistry-A European Journal,2002,8:1424-1429.
[225] ZHU S, ZHANG J, SONG Y, et al. Fluorescent Nanocomposite Based on PVAPolymer Dots [J]. Acta Chimica Sinica,2012,70:2311.
[226] ZHANG H, LIU Y, YAO D, et al. Hybridization of inorganic nanoparticles andpolymers to create regular and reversible self-assembly architectures [J]. Chem Soc Rev,2012,41:6066-6088.
[227] SUN H, ZHANG F, WEI H, et al. The effects of composition and surface chemistry onthe toxicity of quantum dots [J]. Journal of Materials Chemistry B,2013,1:6485.
[228] YAN X, CUI X, LI L S. Synthesis of large, stable colloidal graphene quantum dots withtunable size [J]. J Am Chem Soc,2010,132:5944-5945.
[229] YAMAGUCHI R, ITO S, LEE B S, et al. Functionalization of hexa-peri-hexabenzocoronenes: investigation of the substituent effects on a superbenzene [J]. ChemAsian J,2013,8:178-190.
[230] MUELLER M L, YAN X, DRAGNEA B, et al. Slow hot-carrier relaxation in colloidalgraphene quantum dots [J]. Nano Lett,2011,11:56-60.
[231] Lü C, YANG B. High refractive index organic–inorganic nanocomposites: design,synthesis and application [J]. Journal of Materials Chemistry,2009,19:2884.
[232] WANG Y, LI Y, YAN Y, et al. Luminescent carbon dots in a new magnesiumaluminophosphate zeolite [J]. Chem Commun,2013,49:9006-9008.
[233] WEN X, YU P, TOH Y-R, et al. Near-infrared enhanced carbon nanodots by thermallyassisted growth [J]. Applied Physics Letters,2012,101:163107.
[234] LI M, WU W, REN W, et al. Synthesis and upconversion luminescence of N-dopedgraphene quantum dots [J]. Applied Physics Letters,2012,101:103107.
[235] FAN L, ZHU M, LEE X, et al. Direct synthesis of graphene quantum dots by chemicalvapor deposition [J]. Particle&Particle Systems Characterization,2013,30:764-769.
[236] TANG L, JI R, LI X, et al. Size-Dependent structural and optical characteristics ofglucose-derived graphene quantum dots [J]. Particle&Particle Systems Characterization,2013,30:523-531.
[237] ZHANG X, XIE X, WANG H, et al. Enhanced photoresponsive ultrathin graphitic-phase C3N4nanosheets for bioimaging [J]. J Am Chem Soc,2013,135:18-21.
[238] LU Y, ZHANG L, LIN H. The Use of a Microreactor for Rapid Screening of theReaction Conditions and Investigation of the Photoluminescence Mechanism of Carbon Dots[J]. Chemistry-A European Journal,2014,10.1002/chem.201304358.
[239] YANG Y, WU D, HAN S, et al. Bottom-up fabrication of photoluminescent carbondots with uniform morphology via a soft-hard template approach [J]. Chem Commun,2013,49:4920-4922.
[240] ZONG J, ZHU Y, YANG X, et al. Synthesis of photoluminescent carbogenic dots usingmesoporous silica spheres as nanoreactors [J]. Chem Commun,2011,47:764-766.