Preparation and luminescent properties of novel red phosphors for white-light emitting diodes (W-LEDs) application

摘要

A series of Eu~(3+)–Gd~(3+) co-doped solid solution of Ca_(0.54)Sr_(0.46-1.5x-1.5z)Eu_zGd_x (MoO_4)_y (WO4_)_(1y) (x=0.01–0.20, y=0–1.0, z=0.01–0.30) have been prepared by solid-state reactions. It is found that appropriate amount of Mo~(6+) or W~(6+), Eu~(3+) and Gd3+concentrations can enhance the luminescent intensity and improve crystal structure. These phosphors can be effectively excited by ultraviolet light at 394nm and blue light at 465nm (f–f transition) and emits red light (616 nm) with line spectrum. The wavelengths at 394 and 465nm are nicely fitted in with the widely applied output wavelengths of ultraviolet or blue LED chips.