超盐环境下含氮碳气凝胶的制备及其在超级电容器中的应用
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摘要
多孔碳材料因其优异的导电性和稳定性,以及成本低廉等优点而成为当今的研究热点之一。以苯酚、甲醛和三聚氰胺为原料,利用高浓度氯化锌来提供超盐环境,经溶剂热反应后,在氮气中800℃下热解制得了含氮碳气凝胶(NCA)。扫描电子显微镜、拉曼光谱、X射线光电子能谱和氮气吸附等表征结果表明,该含氮碳气凝胶具有分级多孔蜂窝状结构,其比表面积高达729.6 m~2/g。采用三电极测试体系测试了含氮碳气凝胶的电化学性能,结果表明,在三电极体系中,以0.5 mol/L H_2SO_4作为电解液,含氮碳气凝胶在电流密度为1 A/g时比电容达到350.7 F/g;在电流密度为20 A/g时,经过10000次充放电后,含氮碳气凝胶的电容保持率仍高达97.8%。在双电极体系中,含氮碳气凝胶在800 W/kg的功率密度下,能量密度可达26.8 (W·h)/kg。上述结果表明,该含氮碳气凝胶是一种非常理想的超级电容器电极材料。
Porous carbon materials have become one research hotspot due to their excellent electrical conductivity,superior stability and low cost. Using phenol, formaldehyde and melamine as raw materials, a high concentration of zinc chloride was used to provide a super-salt environment. After solvothermal reaction, a nitrogen-containing carbon aerogel(NCA) was obtained by pyrolysis at 800℃ in nitrogen. Scanning electron microscope(SEM), Raman and Brunauer-Emmett-Teller(BET) results demonstrate that the NCA sample has hierarchically honeycomb-like structure and its specific surface area reaches 729.6 m~2/g. The as-prepared NCA, when tested in three-electrode system as supercapacitor electrode, exhibits a high specific capacitance of 350.7 F/g at 1 A/g and outstanding cycling stability with 97.8 % of the initial capacitance retained after 10000 cycles at 20 A/g in 0.5 mol/L H_2SO_4.Moreover, symmetric supercapacitor based on the NCA electrodes could deliver an impressively high energy density of 26.8(W·h)/kg at a power density of 800 W/kg. Therefore, NCA is one promising material that can be used in supercapacitors.
Porous carbon materials have become one research hotspot due to their excellent electrical conductivity,superior stability and low cost. Using phenol, formaldehyde and melamine as raw materials, a high concentration of zinc chloride was used to provide a super-salt environment. After solvothermal reaction, a nitrogen-containing carbon aerogel(NCA) was obtained by pyrolysis at 800℃ in nitrogen. Scanning electron microscope(SEM), Raman and Brunauer-Emmett-Teller(BET) results demonstrate that the NCA sample has hierarchically honeycomb-like structure and its specific surface area reaches 729.6 m~2/g. The as-prepared NCA, when tested in three-electrode system as supercapacitor electrode, exhibits a high specific capacitance of 350.7 F/g at 1 A/g and outstanding cycling stability with 97.8 % of the initial capacitance retained after 10000 cycles at 20 A/g in 0.5 mol/L H_2SO_4.Moreover, symmetric supercapacitor based on the NCA electrodes could deliver an impressively high energy density of 26.8(W·h)/kg at a power density of 800 W/kg. Therefore, NCA is one promising material that can be used in supercapacitors.
引文
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[42]Fan X M,Yu C,Yang J,et al.Hydrothermal synthesis and activation of graphene-incorporated nitrogen-rich carbon composite for high-performance supercapacitors[J].Carbon,2014,70:130-141.
[43]Chen H,Zhou M,Wang Z,et al.Rich nitrogen-doped ordered mesoporous phenolic resin-based carbon for supercapacitors[J].Electrochimica Acta,2014,148:187-194.
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[50]Wei L,Sevilla M,Fuertes A B,et al.Hydrothermal carbonization of abundant renewable natural organic chemicals for highperformance supercapacitor electrodes[J].Advanced Energy Materials,2011,1(3):356-361.
[2]朱红艳,赵建国,庞明俊,等.石墨烯/δ-MnO2复合材料的制备及其超级电容器性能[J].化工学报,2017,68(12):4824-4832.Zhu H Y,Zhao J G,Pang M J,et al.Preparation of graphene/δ-MnO2composites and supercapacitor performance[J].CIESCJournal,2017,68(12):4824-4832.
[3]周王帆,陈新,曹红亮,等.法国梧桐枯叶基活性炭的制备及其在超级电容器中的应用[J].化工学报,2017,68(7):2918-2924.Zhou W F,Chen X,Cao H L,et al.Preparation of platanus leafbased activated carbon and its application to supercapacitors[J].CIESC Journal,2017,68(7):2918-2924.
[4]Salanne M,Rotenberg B,Naoi K,et al.Efficient storage mechanisms for building better supercapacitors[J].Nature Energy,2016,1(16):16070.
[5]Wang J G,Liu H Z,Sun H H,et al.One-pot synthesis of nitrogendoped ordered mesoporous carbon spheres for high-rate and longcycle life supercapacitors[J].Carbon,2018,127:85-92.
[6]Cheng P,Li T,Yu H,et al.Biomass-derived carbon fiber aerogel as a binder-free electrode for high-rate supercapacitors[J].Journal of Physical Chemistry C,2016,120(4):2079-2086.
[7]Li Y Q,Samad Y A,Polychronopoulou K,et al.Carbon aerogel from winter melon for highly efficient and recyclable oils and organic solvents absorption[J].ACS Sustainable Chemistry Engineering,2014,2(6):1492-1497.
[8]Gueon D,Moon J H.Nitrogen-doped carbon nanotube spherical particles for supercapacitor applications:emulsion-assisted compact packing and capacitance enhancement[J].ACS Applied Materials&Interfaces,2015,7(36):20083-20089.
[9]Du Y X,Liu L B,Xiang Y,et al.Enhanced electrochemical capacitance and oil-absorbability of N-doped graphene aerogel by using amino-functionalized silica as template and doping agent[J].Journal of Power Sources,2018,379:240-248.
[10]Macías C,Rasines G,Lavela P,et al.Mn-containing N-doped monolithic carbon aerogels with enhanced macroporosity as electrodes for capacitive deionization[J].ACS Sustainable Chemistry Engineering,2016,4(5):2487-2494.
[11]Lee E J,Lee Y J,Kim J K,et al.Preparation and characterization of nitrogen-enriched carbon aerogel as a supercapacitor electrode material[J].Journal of Nanoscience and Nanotechnology,2016,16(10):10413-10419.
[12]Xie M J,Dong H H,Zhang D D,et al.Simple synthesis of highly ordered mesoporous carbon by self-assembly of phenolformaldehyde and block copolymers under designed aqueous basic/acidic conditions[J].Carbon,2011,49(7):2459-2464.
[13]Guo J,Wu D L,Wang T,et al.P-doped hierarchical porous carbon aerogels derived from phenolic resins for high performance supercapacitor[J].Applied Surface Science,2019,475:56-66.
[14]Quan X P,Fu Z B,Yuan L,et al.Capacitive deionization of NaCl solutions with ambient pressure dried carbon aerogel microsphere electrodes[J].RSC Advances,2017,7(57):35875-35882.
[15]Yu Z L,Li G C,Fechler N,et al.Polymerization under hypersaline conditions:a robust route to phenolic polymerderived carbon aerogels[J].Angewandte Chemie International Edition,2016,55(47):14623-14627.
[16]Fechler N,Wohlgemuth S A,Philipp J,et al.Salt and sugar:direct synthesis of high surface area carbon materials at low temperatures via hydrothermal carbonization of glucose under hypersaline conditions[J].Journal of Materials Chemistry A,2013,1:9418-9421.
[17]Zeng Y,Wang K,Yao J F,et al.Hollow carbon beads fabricated by phase inversion method for efficient oil sorption[J].Carbon,2014,69:25-31.
[18]Yu M,Li J,Wang L.KOH-activated carbon aerogels derived from sodium carboxymethyl cellulose for high-performance supercapacitors and dye adsorption[J].Chemical Engineering Journal,2017,310:300-306.
[19]Lee W H,Moon J H.Monodispersed N-doped carbon nanospheres for supercapacitor application[J].ACS Applied Materials&Interfaces,2014,6(16):13968-13976.
[20]Zhang J L,Chen L,Zhan G Q,et al.Self-assembly synthesis of N-doped carbon aerogels for supercapacitor and electrocatalytic oxygen reduction[J].ACS Applied Materials&Interfaces,2015,7(23):12760-12766.
[21]Wei X J,Wan S G,Gao S Y.Self-assembly-template engineering nitrogen-doped carbon aerogels for high-rate supercapacitors[J].Nano Energy,2016,28:206-215.
[22]Shang H,Zuo Z C,Zheng H Y,et al.N-doped graphdiyne for high-performance electrochemical electrodes[J].Nano Energy,2018,44:144-154.
[23]Han B,Lee E J,Choi W H,et al.Three-dimensionally ordered mesoporous carbons activated by hot ammonia treatment as highperformance anode materials in lithium-ion batteries[J].New Journal of Chemistry,2015,39(8):6178-6185.
[24]Choi W H,Choi M J,Bang J H.Nitrogen-doped carbon nanocoil array integrated on carbon nanofiber paper for supercapacitor electrodes[J].ACS Applied Materials&Interfaces,2015,7(34):19370-19381.
[25]Gu W T,Sevilla M,Magasinski A,et al.Sulfur-containing activated carbons with greatly reduced content of bottle neck pores for double-layer capacitors:a case study for pseudocapacitance detection[J].Energy&Environmental Science,2013,6(8):2465-2476.
[26]Meng Q S,Qin K Q,Ma L Y,et al.N-doped porous carbon nanofibers/porous silver network hybrid for high-rate supercapacitor electrode[J].ACS Applied Materials&Interfaces,2017,9(36):30832-30839.
[27]Chizari K,Vena A,Laurentius L,et al.The effect of temperature on the morphology and chemical surface properties of nitrogendoped carbon nanotubes[J].Carbon,2014,68:369-379.
[28]Ma K Y,Cheng J P,Liu F,et al.Co-Fe layered double hydroxides nanosheets vertically grown on carbon fiber cloth for electrochemical capacitors[J].Journal of Alloys and Compounds,2016,679:277-284.
[29]Zhou J,Zhang Z S,Xing W,et al.Nitrogen-doped hierarchical porous carbon materials prepared from meta-aminophenol formaldehyde resin for supercapacitor with high rate performance[J].Electrochimica Acta,2015,153:68-75.
[30]Zhang Y,Wen G W,Gao P,et al.High-performance supercapacitor of macroscopic graphene hydrogels by partial reduction and nitrogen doping of graphene oxide[J].Electrochimica Acta,2016,221:167-176.
[31]Chen H,Xiong Y C,Yu T,et al.Boron and nitrogen co-doped porous carbon with a high concentration of boron and its superior capacitive behavior[J].Carbon,2017,113:266-273.
[32]Daems N,Sheng X,Vankelecom I F J,et al.Metal-free doped carbon materials as electrocatalysts for the oxygen reduction reaction[J].Journal of Materials Chemistry A,2014,2:4085-4110.
[33]Yang J,Jo M R,Kang M,et al.Rapid and controllable synthesis of nitrogen doped reduced graphene oxide using microwave-assisted hydrothermal reaction for high power-density supercapacitors[J].Carbon,2014,73:106-113.
[34]Dong Y H,Wang W X,Quan H Y,et al.Nitrogen-doped foamlike carbon plate consisting of carbon tubes as high-performance electrode materials for supercapacitors[J].ChemElectroChem,2016,3(5):814-821.
[35]Du J,Liu L,Hu Z P,et al.Raw-cotton-derived N-doped carbon fiber aerogel as an efficient electrode for electrochemical capacitors[J].ACS Sustainable Chemistry Engineering,2018,6(3):4008-4015.
[36]Sun G L,Ma L Y,Ran J B,et al.Templated synthesis and activation of highly nitrogen-doped worm-like carbon composites based on melamine-urea-formaldehyde resins for high performance supercapacitors[J].Electrochimica Acta,2016,194:168-178.
[37]Mao N,Wang H L,Sui Y,et al.Extremely high-rate aqueous supercapacitor fabricated using doped carbon nanoflakes with large surface area and mesopores at near-commercial mass loading[J].Nano Research,2017,10:1767-1783.
[38]Wang G Q,Zhang J,Kuang S,et al.Nitrogen-doped hierarchical porous carbon as an efficient electrode material for supercapacitors[J].Electrochimica Acta,2015,153:273-279.
[39]Candelaria S L,Uchaker E,Cao G.Comparison of surface and bulk nitrogen modification in highly porous carbon for enhanced supercapacitors[J].Science China Materials,2015,58(7):521-533.
[40]Hao L,Li X L,Zhi L J.Carbonaceous electrode materials for supercapacitors[J].Advanced Materials,2013,25(28):3899-3904.
[41]Shan D D,Yang J,Liu W,et al.Biomass-derived threedimensional honeycomb-like hierarchical structured carbon for ultrahigh energy density asymmetric supercapacitors[J].Journal of Materials Chemistry A,2016,4:13589-13602.
[42]Fan X M,Yu C,Yang J,et al.Hydrothermal synthesis and activation of graphene-incorporated nitrogen-rich carbon composite for high-performance supercapacitors[J].Carbon,2014,70:130-141.
[43]Chen H,Zhou M,Wang Z,et al.Rich nitrogen-doped ordered mesoporous phenolic resin-based carbon for supercapacitors[J].Electrochimica Acta,2014,148:187-194.
[44]Chen H,Wang G,Chen L,et al.Three-dimensional honeycomblike porous carbon with both interconnected hierarchical porosity and nitrogen self-doping from cotton seed husk for supercapacitor electrode[J].Nanomaterials,2018,8(6):412.
[45]Sun L,Zhou H,Li L,et al.Double soft-template synthesis of nitrogen/sulfur-codoped hierarchically porous carbon materials derived from protic ionic liquid for supercapacitor[J].ACSApplied Materials&Interfaces,2017,9(31):26088-26095.
[46]Xia K S,Huang Z Y,Zheng L,et al.Facile and controllable synthesis of N/P co-doped graphene for high-performance supercapacitors[J].Journal of Power Sources,2017,365:380-388.
[47]Zhao L,Fan L Z,Zhou M Q,et al.Nitrogen-containing hydrothermal carbons with superior performance in supercapacitors[J].Advanced Materials,2010,22(45):5202-5206.
[48]Heimb?ckel R,Kraas S,Hoffmann F,et al.Increase of porosity by combining semi-carbonization and KOH activation of formaldehyde resins to prepare high surface area carbons for supercapacitor applications[J].Applied Surface Science,2018,427:1055-1064.
[49]Wang Z,Zhou M,Chen H,et al.Hierarchical activated mesoporous phenolic-resin-based carbons for supercapacitors[J].Chemistry-An Asian Journal,2014,9(10):2789-2797.
[50]Wei L,Sevilla M,Fuertes A B,et al.Hydrothermal carbonization of abundant renewable natural organic chemicals for highperformance supercapacitor electrodes[J].Advanced Energy Materials,2011,1(3):356-361.