Yan Bing, Xiao Xiuzhen
Department of Chemistry, Tongji University, 200092 Shanghai, China.
Nanoscale Res Lett. 2010 Aug 18;5(12):1962-9. doi: 10.1007/s11671-010-9733-8.
Eu(3+)-doped mixed rare earth orthophosphates (rare earth = La, Y, Gd) have been prepared by hydrothermal technology, whose crystal phase and microstructure both vary with the molar ratio of the mixed rare earth ions. For La(x)Y(1-x)PO(4): Eu(3+), the ion radius distinction between the La(3+) and Y(3+) is so large that only La(0.9)Y(0.1)PO(4): Eu(3+) shows the pure monoclinic phase. For La(x)Gd(1-x)PO(4): Eu(3+) system, with the increase in the La content, the crystal phase structure of the product changes from the hexagonal phase to the monoclinic phase and the microstructure of them changes from the nanorods to nanowires. Similarly, Y(x)Gd(1-x)PO(4): Eu(3+), Y(0.1)Gd(0.9)PO(4): Eu(3+) and Y(0.5)Gd(0.5)PO(4): Eu(3+) samples present the pure hexagonal phase and nanorods microstructure, while Y(0.9)Gd(0.1)PO(4): Eu(3+) exhibits the tetragonal phase and nanocubic micromorphology. The photoluminescence behaviors of Eu(3+) in these hosts are strongly related to the nature of the host (composition, crystal phase and microstructure).
采用水热法制备了掺铕（Eu(3+)）的混合稀土正磷酸盐（稀土 = 镧（La）、钇（Y）、钆（Gd）），其晶相和微观结构均随混合稀土离子的摩尔比而变化。对于La(x)Y(1-x)PO(4): Eu(3+)，La(3+)和Y(3+)之间的离子半径差异很大，以至于只有La(0.9)Y(0.1)PO(4): Eu(3+)呈现纯单斜相。对于La(x)Gd(1-x)PO(4): Eu(3+)体系，随着La含量的增加，产物的晶相结构从六方相转变为单斜相，其微观结构从纳米棒变为纳米线。类似地，Y(x)Gd(1-x)PO(4): Eu(3+)、Y(0.1)Gd(0.9)PO(4): Eu(3+)和Y(0.5)Gd(0.5)PO(4): Eu(3+)样品呈现纯六方相和纳米棒微观结构，而Y(0.9)Gd(0.1)PO(4): Eu(3+)表现出四方相和纳米立方微观形态。Eu(3+)在这些基质中的光致发光行为与基质的性质（组成、晶相和微观结构）密切相关。
