Er^(3+)掺杂量对TiO_(2):Er粉体上转换发光性能的影响

Influence of Er^(3+)-doping amount on the upconversion luminescence properties of TiO_(2)∶Er nanopowders

通过溶胶-凝胶法制备了Er^(3+)离子掺杂的TiO_(2)纳米粉体。通过X射线衍射、荧光检测对制备的纳米晶微结构、发光性能进行了表征。结果表明:纳米晶微结构及粒径随掺杂量呈规律性变化,掺杂稀土离子可抑制其相变。在980nm红外激光泵浦下,其发射峰分别位于527nm、548nm、660nm处,通过改变Er^(3+)掺杂量,获得绿红强度比最高为29.3,最低为0.7,实现了单一掺杂改变发光颜色的调控。借助交叉弛豫与浓度猝灭理论,解释了其发光性能的规律性变化,并分析了其上转换机制。

Er^(3+)ion-doped TiO_(2) nanopowders were prepared by sol-gel method.The microstructure and luminescence properties of the prepared nanocrystals were characterized by XRD and FA.The results showed that the microstructure and particle size changed regularly with doping amount.The crystal phase transition could be suppressed by doping rare earth ions.The emission peaks were located at 527nm,548nm,660nm,respectively,upon excitation with 980nm infrared laser.By changing the Er^(3+)doping amount,the highest green-red intensity ratio was 29.3 and the lowest was 0.7,realizing the control of light-emitting color by a single doping.With the help of cross-relaxation and concentration quenching theory,the regular variation of luminescence performance was explained and the upconversion luminescence mechanism was analyzed.