在当今日新月异的科技时代,光电材料的发展正以前所未有的速度推动着科技革命的步伐。作为当前光电材料领域的明星,量子点以其独特的光电性能,在太阳电池、发光二极管、生物成像、光电探测器等领域都展现出巨大的应用前景和革命性的变...在当今日新月异的科技时代,光电材料的发展正以前所未有的速度推动着科技革命的步伐。作为当前光电材料领域的明星,量子点以其独特的光电性能,在太阳电池、发光二极管、生物成像、光电探测器等领域都展现出巨大的应用前景和革命性的变革。量子点材料最早可以追溯到1981年,苏联固体物理学家AlexeiI.Ekimov在玻璃中首次发现了尺寸相关的量子效应;在同时期,美国物理学家Louis E. Brus发现了量子限域效应,并提出了著名的Brus方程,为量子点的研究奠定了重要的理论基础;到了1993年,美国化学家Moungi G. Bawendi革新了量子点的化学合成方法,显著提高了量子点的质量,推动了量子点研究和应用的蓬勃发展。展开更多
In this work, we have studied the concentration quenching in transparent glass ceramics containing Er^3＋：NaYF4 nanocrystals. For different concentrations, the emission spectra and decay curves of the ^4I/3/2 → ^4I1...In this work, we have studied the concentration quenching in transparent glass ceramics containing Er^3＋：NaYF4 nanocrystals. For different concentrations, the emission spectra and decay curves of the ^4I/3/2 → ^4I15/2 emission were measured. The Er-concentration dependence of integrated intensity and lifetime of ^4I13/2→^4I15/2 emission are showed. With the increase of the Er^3＋ doping concentration, the 1.5 μm fluorescence emission first increases, then decreases, and the lifetime falls gradually. With 980 nm excitation, the efficiency of the energy transfer from Er^3＋ to quenching centers reaches 73.73% for the sample with 4 mol% Er^3＋. Meanwhile, owing to the relation of fluorescence integrated intensity and Er-concentration, a dipole-dipole quenching mechanism in the framework of a limited diffusion regime has been proved. Using the limited diffusion case, the critical concentration for quenching has been determined from a fitting equation of the lifetime and Er-concentration. The fit- ting result shows the critical concentration for quenching is higher than the values obtained in Er-doped different glass by an order of magnitude.展开更多
文摘在当今日新月异的科技时代,光电材料的发展正以前所未有的速度推动着科技革命的步伐。作为当前光电材料领域的明星,量子点以其独特的光电性能,在太阳电池、发光二极管、生物成像、光电探测器等领域都展现出巨大的应用前景和革命性的变革。量子点材料最早可以追溯到1981年,苏联固体物理学家AlexeiI.Ekimov在玻璃中首次发现了尺寸相关的量子效应;在同时期,美国物理学家Louis E. Brus发现了量子限域效应,并提出了著名的Brus方程,为量子点的研究奠定了重要的理论基础;到了1993年,美国化学家Moungi G. Bawendi革新了量子点的化学合成方法,显著提高了量子点的质量,推动了量子点研究和应用的蓬勃发展。
基金supported by the Fujian Natural Science Foundation of China (Grant No. 2009J05139)the Fujian Science and Technology major projects of China (Grant No. 2007HJ0004-2)+1 种基金the Project of Education Department of Fujian Province of China (Grant No. JK2011008)the Innovation Project for Young Scientists of Fujian Province of China (Grant No. 2007F3027)
文摘In this work, we have studied the concentration quenching in transparent glass ceramics containing Er^3＋：NaYF4 nanocrystals. For different concentrations, the emission spectra and decay curves of the ^4I/3/2 → ^4I15/2 emission were measured. The Er-concentration dependence of integrated intensity and lifetime of ^4I13/2→^4I15/2 emission are showed. With the increase of the Er^3＋ doping concentration, the 1.5 μm fluorescence emission first increases, then decreases, and the lifetime falls gradually. With 980 nm excitation, the efficiency of the energy transfer from Er^3＋ to quenching centers reaches 73.73% for the sample with 4 mol% Er^3＋. Meanwhile, owing to the relation of fluorescence integrated intensity and Er-concentration, a dipole-dipole quenching mechanism in the framework of a limited diffusion regime has been proved. Using the limited diffusion case, the critical concentration for quenching has been determined from a fitting equation of the lifetime and Er-concentration. The fit- ting result shows the critical concentration for quenching is higher than the values obtained in Er-doped different glass by an order of magnitude.
