中文摘要：

采用溶胶-凝胶法制备了上转换材料LiLa（MoO4）2：Yb^3＋，Er^3＋（Tm^3＋），并对其进行了X射线衍射分析以及荧光光谱测定．在980nm红外激光器激发下，LiLa（MoO4）2：Yb^3＋，Er^3＋发出波长为530nm和550nm的绿色可见光，而LiLa（MoO4）2：Yb^3＋,Tm^3＋发出波长为475nm的蓝色可见光．对Yb^3＋／Er^3＋和Yb^3＋／Tm^3＋双掺体系的上转换发光机理进行了探讨，其中Er^3＋发出绿色上转换光的过程为双光子过程，而Tm^3＋发出蓝色上转换光的过程为三光子过程。

英文摘要：

Upconversion materials LiLa（ MoO4 ） 2 ： Yb3^ ＋ , Er^3＋ （ Tm^3 ＋） were synthesized by the sol-gel method. The as-prepared samples were characterized by the X-ray diffraction and the upconversion luminescence spectra were recorded by a spectrophotometer. Under a 980 nm semiconductor laser excitation, green upconversion emissions of LiLa （MoO4 ）2：Yb^3＋ , Er^3＋ at 530 nm and 550 nm can be observed, while the blue emission of LiLa（MoO4）2：Yb^＋3 , Tm^3＋at 475 nm can be seen by naked eye. Moreover, the upconversion mechanisms is discussed in our paper, the upconversion luminescences of Er^3＋ and Tm^3＋ are produced through a two-photon and a three-photon process, respectively.