Yb^(3+)/Er^(3+)共掺BaGd_2O_4荧光粉的制备及其上转换发光性质

Synthesis and Characterization of Up-conversion Luminescence Material Er^(3+)/Yb^(3+) Co-doped BaGd_2O_4

采用溶胶-凝胶法制备了Yb3+/Er3+共掺杂BaGd2O4上转换荧光粉。研究了退火温度对BaGd2O4晶体结构的影响,以及Yb3+/Er3+共掺杂的BaGd2O4荧光粉在971 nm LED激发下,激发密度与上转换发射光功率及效率的关系。研究结果表明,尽管BaGd2O4与目前报道效率最高的Yb3+/Er3+共掺杂BaGd2ZnO5基质的最高声子能量相同,但光-光转换效率却相差82倍,极值量子效率相差7.8倍。结论认为,在声子能量不是很高的情况下,材料结构是影响上转换效率的主要因素。

Yb3+/Er3+co-doped BaGd2O4 phosphors were prepared by the sol-gel method. The influence of annealing temperature on BaGd2O4 crystal structure was investigated. Under 971 nm excitation,the dependence of the emission power and the up-conversion efficiency on the excitation density was studied. The obtained data show that the light conversion and absolute quantum efficiency of BaGd2O4∶Yb3+,Er3+ are 82 and 7. 8 times smaller than that of BaGd2ZnO5∶Yb3+,Er3+,respectively. But the phonon energy of BaGd2O4 is almost the same with that of BaGd2ZnO5∶Yb3+,Er3+ which possesses the highest efficiency as ever reported. So,we can conclude that the material structure is the main influencing factor on the up-conversion efficiency when the phonon energy of the host is not very high.