NaYF_4:Er~（3+）/Yb~（3+）上转换发光增强和光谱设计
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摘要
稀土掺杂发光纳米晶体在太阳能电池、生物标记、发光器件、激光防伪等领域有着广阔的应用前景。而低上转换发光效率是限制其实际应用的主要因素。探索提高上转换发光强度的方法,不仅具有重要的理论研究价值,而且具有重要的现实意义。NaYF_4:Er~(3+)/Yb~(3+)组合的纳米晶由于其较强的发光强度和丰富的荧光光谱而广受关注。论文主要围绕“NaYF_4:Er~(3+)/Yb~(3+)上转换发光增强和光谱设计”开展系列研究工作。
利用油热法制备了不同尺寸的立方相和六方相NaYF_4:Er~(3+)/Yb~(3+)纳米球和柱状纳米晶。通过改变反应时间、反应温度和调节NH4F/NaF与稀土离子的比例,发展了一种制备上转换荧光性能更好的六方相NaYF_4柱状纳米晶的新方法。通过红外吸收谱和荧光光谱的探测,阐明了上转换发光增强机制。
利用已探索出的柱状纳米晶的合成方法,合成一批NaYF_4:Er~(3+)/Yb~(3+)纳米棒,改变敏化剂Yb~(3+)的浓度,在保持纳米晶形状和晶格结构不变的情况下,成功地提出了一种提高上转换发光强度和光谱调节的方法,为单色红光的获得指出了一个新方向,并在氟化物中证明了Er~(3+)和Yb~(3+)离子之间反向能量传递过程的存在。
在NaYF_4:Er_(0.02)~(3+)/Yb_(0.2)~(3+)的稀土材料中,引入了新的掺杂离子——Ce~(3+)离子,利用Ce~(3+)离子和Er~(3+)离子特殊的能级匹配关系,通过能级间的交叉弛豫,成功地对Er~(3+)的上转换荧光光谱进行调节,为单绿色上转换发光的获得提供了一个新思路。
Lanthanide-doped luminescent nanocrystals have great potentials in the field of solar cells, biological labels, optical devices, and anticounterfeiting applications. Low upconversion efficiency, however, still constitutes the main limit for its practical application. To meet the requirement, developing new technologies to enhance upconversion luminescence is very important both to fundamental research and practical application. NaYF4:Er~(3+)/Yb~(3+) nanocrystals have attracted more attention due to the high efficiency and rich spectrum. This dissertation presents a systematic research surrounding the issue of luminescence enhancement and designation of NaYF4:Er~(3+)/Yb~(3+) nanocrystals.
Cubic and hexagonal phase NaYF4:Er~(3+)/Yb~(3+) nanorods were prepared based on the solvo-thermal method. By prolonging the reaction time, raising the reaction temperature, and increasing the ratio of NH_4F/NaF to lanthanide, a facile method was successfully developed, which can prepare hexagonal phase NaYF4 with proper luminescence easily. Assisted by testing the spectra and Infra-red absorption spectrum, we discussed the physical mechanism of luminescence enhancement.
Taking advantage of the method mentioned above, we fabricated a serial of NaYF4:Er~(3+)/Yb~(3+) nanorods. By changing concentration of Yb~(3+), a method for enhancing and manipulating luminescence simultaneously was developed, without influencing structure as well as the size of nanorods. It’s also a great potential model for single-red light. Moreover, we proved energy back transfer process from Er~(3+) to Yb~(3+) ions in fluoride materials.
In NaYF4:Er~(3+)/Yb~(3+) nanomaterials, Ce~(3+) was tri-doped into the system as a new ion. By using the proper match between Er~(3+) and Ce~(3+) ions, with the help of cross relaxation in the system, upconversion luminescence of Er~(3+) was modulated. In addition, it also paves a way for obtaining single-green luminescence.
利用油热法制备了不同尺寸的立方相和六方相NaYF_4:Er~(3+)/Yb~(3+)纳米球和柱状纳米晶。通过改变反应时间、反应温度和调节NH4F/NaF与稀土离子的比例,发展了一种制备上转换荧光性能更好的六方相NaYF_4柱状纳米晶的新方法。通过红外吸收谱和荧光光谱的探测,阐明了上转换发光增强机制。
利用已探索出的柱状纳米晶的合成方法,合成一批NaYF_4:Er~(3+)/Yb~(3+)纳米棒,改变敏化剂Yb~(3+)的浓度,在保持纳米晶形状和晶格结构不变的情况下,成功地提出了一种提高上转换发光强度和光谱调节的方法,为单色红光的获得指出了一个新方向,并在氟化物中证明了Er~(3+)和Yb~(3+)离子之间反向能量传递过程的存在。
在NaYF_4:Er_(0.02)~(3+)/Yb_(0.2)~(3+)的稀土材料中,引入了新的掺杂离子——Ce~(3+)离子,利用Ce~(3+)离子和Er~(3+)离子特殊的能级匹配关系,通过能级间的交叉弛豫,成功地对Er~(3+)的上转换荧光光谱进行调节,为单绿色上转换发光的获得提供了一个新思路。
Lanthanide-doped luminescent nanocrystals have great potentials in the field of solar cells, biological labels, optical devices, and anticounterfeiting applications. Low upconversion efficiency, however, still constitutes the main limit for its practical application. To meet the requirement, developing new technologies to enhance upconversion luminescence is very important both to fundamental research and practical application. NaYF4:Er~(3+)/Yb~(3+) nanocrystals have attracted more attention due to the high efficiency and rich spectrum. This dissertation presents a systematic research surrounding the issue of luminescence enhancement and designation of NaYF4:Er~(3+)/Yb~(3+) nanocrystals.
Cubic and hexagonal phase NaYF4:Er~(3+)/Yb~(3+) nanorods were prepared based on the solvo-thermal method. By prolonging the reaction time, raising the reaction temperature, and increasing the ratio of NH_4F/NaF to lanthanide, a facile method was successfully developed, which can prepare hexagonal phase NaYF4 with proper luminescence easily. Assisted by testing the spectra and Infra-red absorption spectrum, we discussed the physical mechanism of luminescence enhancement.
Taking advantage of the method mentioned above, we fabricated a serial of NaYF4:Er~(3+)/Yb~(3+) nanorods. By changing concentration of Yb~(3+), a method for enhancing and manipulating luminescence simultaneously was developed, without influencing structure as well as the size of nanorods. It’s also a great potential model for single-red light. Moreover, we proved energy back transfer process from Er~(3+) to Yb~(3+) ions in fluoride materials.
In NaYF4:Er~(3+)/Yb~(3+) nanomaterials, Ce~(3+) was tri-doped into the system as a new ion. By using the proper match between Er~(3+) and Ce~(3+) ions, with the help of cross relaxation in the system, upconversion luminescence of Er~(3+) was modulated. In addition, it also paves a way for obtaining single-green luminescence.
引文
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2 Z. Y. Liu, G. S. Yi, H. T. Zhang, J. Ding, Y. W. Zhang, and J. M. Xue. Monodisperse Silica Nanoparticles Encapsulating Upconversion Fluorescent and Superparamagnetic Nanocrystals. Chemical Communications. 2008, 6: 694-696
3 H. C. Lu, G. S. Yi, S. Y. Zhao, D. P. Chen, L. H. Guo, and J. Cheng. Synthesis and Characterization of Multi-Functional Nanoparticles Possessing Magnetic, up-Conversion Fluorescence and Bio-Affinity Properties. Journal of Materials Chemistry. 2004, 14(8): 1336-1341
4 D. Nagao, M. Yokoyama, N. Yamauchi, H. Matsumoto, Y. Kobayashi, and M. Konno. Synthesis of Highly Monodisperse Particles Composed of a Magnetic Core and Fluorescent Shell. Langmuir. 2008, 24(17): 9804-9808
5 J. M. Rivera-Ortiz. Synthesis and Characterization of New Multi-Functional Dendrimer-Based Probes. Journal of Histochemistry & Cytochemistry. 2004, 52: S16-S16
6 T. Y. Cao, T. S. Yang, Y. Gao, Y. Yang, H. Hu, and F. Y. Li. Water-Soluble NaYF4:Yb/Er Upconversion Nanophosphors: Synthesis, Characteristics and Application in Bioimaging. Inorganic Chemistry Communications. 2010, 13(3): 392-394
7 F. Vetrone, R. Naccache, A. J. de la Fuente, F. Sanz-Rodriguez, A. Blazquez-Castro, E. M. Rodriguez, D. Jaque, J. G. Sole, and J. A. Capobianco. Intracellular Imaging of Hela Cells by Non-Functionalized NaYF4 : Er~(3+), Yb~(3+) Upconverting Nanoparticles. Nanoscale. 2010, 2(4): 495-498
8 A. Shalav, B. S. Richards, T. Trupke, K. W. Kramer, and H. U. Gudel.Application of NaYF_4 : Er~(3+) Upconverting Phosphors for Enhanced Near-Infrared Silicon Solar Cell Response. Applied Physics Letters. 2005, 86(1): 013505(3)
9 F. Wang, and X. G. Liu. Recent Advances in the Chemistry of Lanthanide-Doped Upconversion Nanocrystals. Chemical Society Reviews. 2009, 38(4): 976-989
10 F. Auzel. Upconversion and Anti-Stokes Processes with f and d Ions in Solids. Chemical Reviews. 2004, 104(1): 139-173
11 H. Schafer, P. Ptacek, K. Kompe, and M. Haase. Lanthanide-Doped NaYF_4 Nanocrystals in Aqueous Solution Displaying Strong Upconversion Emission. Chemistry of Materials. 2007, 19(6): 1396-1400
12 J. M. J. M. Zijlmans, M. Vanderkeur, J. H. F. Falkenburg, R. Willemze, and W. E. Fibbe. Identification of Multi-Lineage-Colony-Forming Cells in the Cd34(+)/Cd45ra(-)/Rhodamine Cell Fraction Using Sequential Facs Analysis of Colonies from Single Cord Blood-Derived Progenitor Cells. Experimental Hematology. 1993, 21(8): 1069-1069
13 H. Xu, Z. Dai, and Z. Jiang. Luminescence Characteristics of Ultraviolet Upconversion from Er-3 : Yag Crystal by Ar~+ Laser (488 nm) Excitation. European Physical Journal D. 2001, 17(1): 79-83
14 G. Y. Chen, H. C. Liu, G. Somesfalean, Y. Q. Sheng, H. J. Liang, Z. G. Zhang, Q. Sun, and F. P. Wang. Enhancement of the Upconversion Radiation in Y2O3 : Er~(3+) Nanocrystals by Codoping with Li+ Ions. Applied Physics Letters. 2008, 92(11): 113114(3)
15 S. Schietinger, T. Aichele, H. Q. Wang, T. Nann, and O. Benson. Plasmon-Enhanced Upconversion in Single NaYF_4:Yb3+/Er~(3+) Codoped Nanocrystals. Nano Letters. 2010, 10(1): 134-138
16 Z. Q. Li, and Y. Zhang. An Efficient and User-Friendly Method for the Synthesis of Hexagonal-Phase NaYF_4:Yb, Er/Tm Nanocrystals with Controllable Shape and Upconversion Fluorescence. Nanotechnology. 2008,19(34): 345606(5)
17 M. Bitenc, P. Podbrscek, Z. C. Orel, M. A. Cleveland, J. A. Paramo, R. M. Peters, and Y. M. Strzhemechny. Correlation between Morphology and Defect Luminescence in Precipitated ZnO Nanorod Powders. Crystal Growth & Design. 2009, 9(2): 997-1001
18 X. X. Zhang, D. F. Liu, L. H. Zhang, W. L. Li, M. Gao, W. J. Ma, Y. Ren, Q. S. Zeng, Z. Q. Niu, W. Y. Zhou, and S. S. Xie. Synthesis of Large-Scale Periodic ZnO Nanorod Arrays and Its Blue-Shift of UV Luminescence. Journal of Materials Chemistry. 2009, 19(7): 962-969
19 D. X. Jiang, L. X. Cao, G. Su, W. Liu, H. Qu, Y. G. Sun, and B. H. Dong. Synthesis and Luminescence Properties of ZnS:Mn/ZnS Core/Shell Nanorod Structures. Journal of Materials Science. 2009, 44(11): 2792-2795
20 J. S. Zhang, W. P. Qin, J. S. Zhang, Y. Wan, C. Y. Cao, Y. Jin, G. D. Wei, G. F. Wang, and L. L. Wang. Microwave-Assisted Solvothermal Synthesis of YF3 : Yb~(3+), Tm~(3+) Nanobundles. Chemical Research in Chinese Universities. 2007, 23(6): 733-735
21 F. Wang, Y. Han, C. S. Lim, Y. H. Lu, J. Wang, J. Xu, H. Y. Chen, C. Zhang, M. H. Hong, and X. G. Liu. Simultaneous Phase and Size Control of Upconversion Nanocrystals through Lanthanide Doping. Nature. 2010, 463(7284): 1061-1065
22 M. Wang, C. C. Mi, Y. X. Zhang, J. L. Liu, F. Li, C. B. Mao, and S. K. Xu. Nir-Responsive Silica-Coated NaYbF_4:Er/Tm/Ho Upconversion Fluorescent Nanoparticles with Tunable Emission Colors and Their Applications in Immunolabeling and Fluorescent Imaging of Cancer Cells. Journal of Physical Chemistry C. 2009, 113(44): 19021-19027
23 G. Y. Chen, H. C. Liu, G. Somesfalean, H. J. Liang, and Z. G. Zhang. Upconversion Emission Tuning from Green to Red in Yb~(3+)/Ho3+-Codoped NaYF_4 Nanocrystals by Tridoping with Ce3+ Ions. Nanotechnology. 2009, 20(38): 385704(6)
24 F. Wang, and X. G. Liu. Upconversion Multicolor Fine-Tuning: Visible to near-Infrared Emission from Lanthanide-Doped NaYF_4 Nanoparticles. Journal of the American Chemical Society. 2008, 130(17): 5642- 5643
25 Y. J. Sun, Y. Chen, L. J. Tian, Y. Yu, X. G. Kong, J. W. Zhao, and H. Zhang. Controlled Synthesis and Morphology Dependent Upconversion Luminescence of NaYF_4 : Yb, Er Nanocrystals. Nanotechnology. 2007, 18(27): 275609(9)
26 H. X. Mai, Y. W. Zhang, L. D. Sun, and C. R. Yan. Size- and Phase-Controlled Synthesis of Monodisperse NaYF_4: Yb,Er Nanocrystals from a Unique Delayed Nucleation Pathway Monitored with Upconversion Spectroscopy. Journal of Physical Chemistry C. 2007, 111(37): 13730-13739
27 H. X. Mai, Y. W. Zhang, L. D. Sun, and C. H. Yan. Size-and Phase-Controlled Synthesis of Monodisperse NaYF_4: Yb, Er Nanocrystals from a Unique Delayed Nucleation Pathway Monitored with Upconversion Spectroscopy. Journal of Physical Chemistry C. 2007, 111 (37): 13730–13739
28 Y. Sun, Y. Chen, L. Tian, Y. Yu, X. Kong, J. Zhao, and H. Zhang. Controlled Synthesis and Morphology Dependent Upconversion Luminescence of NaYF_4: Yb, Er Nanocrystals. Nanotechnology. 2007, 18(27): 275609(9)
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43 G. P. Dong, X. F. Liu, X. D. Xiao, B. Qian, J. Ruan, S. Ye, H. C. Yang, D. P. Chen, and J. R. Qiu. Photoluminescence of Ag Nanoparticle Embedded Tb~(3+)/Ce~(3+) Codoped NaYF_4/PVP Nanofibers Prepared by Electrospinning. Nanotechnology. 2009, 20(5): 055707(6)
2 Z. Y. Liu, G. S. Yi, H. T. Zhang, J. Ding, Y. W. Zhang, and J. M. Xue. Monodisperse Silica Nanoparticles Encapsulating Upconversion Fluorescent and Superparamagnetic Nanocrystals. Chemical Communications. 2008, 6: 694-696
3 H. C. Lu, G. S. Yi, S. Y. Zhao, D. P. Chen, L. H. Guo, and J. Cheng. Synthesis and Characterization of Multi-Functional Nanoparticles Possessing Magnetic, up-Conversion Fluorescence and Bio-Affinity Properties. Journal of Materials Chemistry. 2004, 14(8): 1336-1341
4 D. Nagao, M. Yokoyama, N. Yamauchi, H. Matsumoto, Y. Kobayashi, and M. Konno. Synthesis of Highly Monodisperse Particles Composed of a Magnetic Core and Fluorescent Shell. Langmuir. 2008, 24(17): 9804-9808
5 J. M. Rivera-Ortiz. Synthesis and Characterization of New Multi-Functional Dendrimer-Based Probes. Journal of Histochemistry & Cytochemistry. 2004, 52: S16-S16
6 T. Y. Cao, T. S. Yang, Y. Gao, Y. Yang, H. Hu, and F. Y. Li. Water-Soluble NaYF4:Yb/Er Upconversion Nanophosphors: Synthesis, Characteristics and Application in Bioimaging. Inorganic Chemistry Communications. 2010, 13(3): 392-394
7 F. Vetrone, R. Naccache, A. J. de la Fuente, F. Sanz-Rodriguez, A. Blazquez-Castro, E. M. Rodriguez, D. Jaque, J. G. Sole, and J. A. Capobianco. Intracellular Imaging of Hela Cells by Non-Functionalized NaYF4 : Er~(3+), Yb~(3+) Upconverting Nanoparticles. Nanoscale. 2010, 2(4): 495-498
8 A. Shalav, B. S. Richards, T. Trupke, K. W. Kramer, and H. U. Gudel.Application of NaYF_4 : Er~(3+) Upconverting Phosphors for Enhanced Near-Infrared Silicon Solar Cell Response. Applied Physics Letters. 2005, 86(1): 013505(3)
9 F. Wang, and X. G. Liu. Recent Advances in the Chemistry of Lanthanide-Doped Upconversion Nanocrystals. Chemical Society Reviews. 2009, 38(4): 976-989
10 F. Auzel. Upconversion and Anti-Stokes Processes with f and d Ions in Solids. Chemical Reviews. 2004, 104(1): 139-173
11 H. Schafer, P. Ptacek, K. Kompe, and M. Haase. Lanthanide-Doped NaYF_4 Nanocrystals in Aqueous Solution Displaying Strong Upconversion Emission. Chemistry of Materials. 2007, 19(6): 1396-1400
12 J. M. J. M. Zijlmans, M. Vanderkeur, J. H. F. Falkenburg, R. Willemze, and W. E. Fibbe. Identification of Multi-Lineage-Colony-Forming Cells in the Cd34(+)/Cd45ra(-)/Rhodamine Cell Fraction Using Sequential Facs Analysis of Colonies from Single Cord Blood-Derived Progenitor Cells. Experimental Hematology. 1993, 21(8): 1069-1069
13 H. Xu, Z. Dai, and Z. Jiang. Luminescence Characteristics of Ultraviolet Upconversion from Er-3 : Yag Crystal by Ar~+ Laser (488 nm) Excitation. European Physical Journal D. 2001, 17(1): 79-83
14 G. Y. Chen, H. C. Liu, G. Somesfalean, Y. Q. Sheng, H. J. Liang, Z. G. Zhang, Q. Sun, and F. P. Wang. Enhancement of the Upconversion Radiation in Y2O3 : Er~(3+) Nanocrystals by Codoping with Li+ Ions. Applied Physics Letters. 2008, 92(11): 113114(3)
15 S. Schietinger, T. Aichele, H. Q. Wang, T. Nann, and O. Benson. Plasmon-Enhanced Upconversion in Single NaYF_4:Yb3+/Er~(3+) Codoped Nanocrystals. Nano Letters. 2010, 10(1): 134-138
16 Z. Q. Li, and Y. Zhang. An Efficient and User-Friendly Method for the Synthesis of Hexagonal-Phase NaYF_4:Yb, Er/Tm Nanocrystals with Controllable Shape and Upconversion Fluorescence. Nanotechnology. 2008,19(34): 345606(5)
17 M. Bitenc, P. Podbrscek, Z. C. Orel, M. A. Cleveland, J. A. Paramo, R. M. Peters, and Y. M. Strzhemechny. Correlation between Morphology and Defect Luminescence in Precipitated ZnO Nanorod Powders. Crystal Growth & Design. 2009, 9(2): 997-1001
18 X. X. Zhang, D. F. Liu, L. H. Zhang, W. L. Li, M. Gao, W. J. Ma, Y. Ren, Q. S. Zeng, Z. Q. Niu, W. Y. Zhou, and S. S. Xie. Synthesis of Large-Scale Periodic ZnO Nanorod Arrays and Its Blue-Shift of UV Luminescence. Journal of Materials Chemistry. 2009, 19(7): 962-969
19 D. X. Jiang, L. X. Cao, G. Su, W. Liu, H. Qu, Y. G. Sun, and B. H. Dong. Synthesis and Luminescence Properties of ZnS:Mn/ZnS Core/Shell Nanorod Structures. Journal of Materials Science. 2009, 44(11): 2792-2795
20 J. S. Zhang, W. P. Qin, J. S. Zhang, Y. Wan, C. Y. Cao, Y. Jin, G. D. Wei, G. F. Wang, and L. L. Wang. Microwave-Assisted Solvothermal Synthesis of YF3 : Yb~(3+), Tm~(3+) Nanobundles. Chemical Research in Chinese Universities. 2007, 23(6): 733-735
21 F. Wang, Y. Han, C. S. Lim, Y. H. Lu, J. Wang, J. Xu, H. Y. Chen, C. Zhang, M. H. Hong, and X. G. Liu. Simultaneous Phase and Size Control of Upconversion Nanocrystals through Lanthanide Doping. Nature. 2010, 463(7284): 1061-1065
22 M. Wang, C. C. Mi, Y. X. Zhang, J. L. Liu, F. Li, C. B. Mao, and S. K. Xu. Nir-Responsive Silica-Coated NaYbF_4:Er/Tm/Ho Upconversion Fluorescent Nanoparticles with Tunable Emission Colors and Their Applications in Immunolabeling and Fluorescent Imaging of Cancer Cells. Journal of Physical Chemistry C. 2009, 113(44): 19021-19027
23 G. Y. Chen, H. C. Liu, G. Somesfalean, H. J. Liang, and Z. G. Zhang. Upconversion Emission Tuning from Green to Red in Yb~(3+)/Ho3+-Codoped NaYF_4 Nanocrystals by Tridoping with Ce3+ Ions. Nanotechnology. 2009, 20(38): 385704(6)
24 F. Wang, and X. G. Liu. Upconversion Multicolor Fine-Tuning: Visible to near-Infrared Emission from Lanthanide-Doped NaYF_4 Nanoparticles. Journal of the American Chemical Society. 2008, 130(17): 5642- 5643
25 Y. J. Sun, Y. Chen, L. J. Tian, Y. Yu, X. G. Kong, J. W. Zhao, and H. Zhang. Controlled Synthesis and Morphology Dependent Upconversion Luminescence of NaYF_4 : Yb, Er Nanocrystals. Nanotechnology. 2007, 18(27): 275609(9)
26 H. X. Mai, Y. W. Zhang, L. D. Sun, and C. R. Yan. Size- and Phase-Controlled Synthesis of Monodisperse NaYF_4: Yb,Er Nanocrystals from a Unique Delayed Nucleation Pathway Monitored with Upconversion Spectroscopy. Journal of Physical Chemistry C. 2007, 111(37): 13730-13739
27 H. X. Mai, Y. W. Zhang, L. D. Sun, and C. H. Yan. Size-and Phase-Controlled Synthesis of Monodisperse NaYF_4: Yb, Er Nanocrystals from a Unique Delayed Nucleation Pathway Monitored with Upconversion Spectroscopy. Journal of Physical Chemistry C. 2007, 111 (37): 13730–13739
28 Y. Sun, Y. Chen, L. Tian, Y. Yu, X. Kong, J. Zhao, and H. Zhang. Controlled Synthesis and Morphology Dependent Upconversion Luminescence of NaYF_4: Yb, Er Nanocrystals. Nanotechnology. 2007, 18(27): 275609(9)
29 X. Chen, W. Wang, J. Bi, L. Wu, Z. Li, and X. Fu. Microwave Hydrothermal Synthesis and Upconversion Properties of NaYF_4: Yb3+, Tm3+ with Microtube Morphology. Materials Letters. 2009, 63(12): 1023-1026
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