Combinatorial study of the optimization of Y2O3:Bi,Eu red phosphors.

The present investigation aims at the synthesis of (Y2-xEuxBiy)O3 red phosphor materials using the combinatorial chemistry method. We developed square-type arrays consisting of 90 compositions to obtain the optimum composition of co-dopants in a Y2O3 host. The optimized composition was found to be (Y2-xEuxBiy)O3 (x = 0.16-0.18, y = 0.08-0.10). The screening of the compositions was investigated by analysis of the emission spectrum under 365 nm UV excitation arising from the energy transfer between Bi3+ and Eu3+ ions. The results of the photoluminescence excited by ultraviolet agree well with the conventional-scale synthesis results, indicating that the combinatorial screening method is fast, reliable, reproducible, and applicable to the study of powder materials with relatively quick calcinations at high synthesis temperatures.