为进一步提高YVO4材料的下转换发光性能, 在改进后的溶胶-凝胶法制备的YVO4∶Eu3+中, 通过掺入Bi3+来拓宽其在紫外波段的光谱吸收并提高其发光强度, 通过掺入P5+达到以PO43-部分取代VO43-来改善YVO4∶Eu3+的光输出稳定性及温度猝灭特性的目的。研究表明, 掺入的Bi3+和 P5+可成功取代YVO4晶格中的Y3+和V5+。当Bi3+掺入量较少时, 样品仍然为四方晶系, Bi3+较好地取代了Y3+的晶格位置, 形成单相的晶体结构。而在掺入少量的P5+之后, YVO4与YPO4之间形成了均匀的固溶体。在350 nm激发光源作用下, 当Bi3+和P5+掺杂摩尔分数分别为0.04和0.10时, 发光强度达到最大, 特别是YV0.90P0.10O4∶0.05Eu3+在619 nm处的发光强度要比YVO4∶0.05Eu3+的发光强度增大1.9倍。

Bismuth (Bi3+) and phosphorus (P3+) ions doped YVO4∶Eu3+ down-conversion materials were prepared by modified sol-gel method to broaden the absorption range of ultraviolet light and enhance the stability of light emission. It is shown that some positions of Yttrium (Y3+) and Vanadium (V5+) ions can be successfully replaced by incorporated Bismuth (Bi3+) and phosphorus (P3+) ions in the YVO4 lattice. As to low Bi3+ doping, the crystal structure is still tetragonal and the position of Y3+ is well substituted by Bi3+. While for low P3+ doping, a homogeneous solid solution is formed between YVO4 and YPO4.Under the excitation of 325 nm, the highest luminescence intensity can be obtained with Bi3+ mole fraction of 0.04 and P5+ mole fraction of 0.10, respectively. In that case, the instensity of YV0.90P0.10O4∶0.05Eu3+ can increase up to 1.9 times comparing to YVO4∶0.05Eu3+.