Bi~(3+) enhanced red emission in Sr_(0.5)Ca_(0.4)MoO_4:Eu~(3+) phosphor

摘要

A series of Eu~(3+) single-doped Sr_(0.9-x)Ca_xMoO_4 and Bi~(3+)-Eu~(3+) co-doped Sr_(0.5)Ca_(0.4)MoO_4 red phosphors were prepared via a co-precipitation reaction. The X-ray diffraction patterns show that doping Bi~(3+) ions in Sr_(0.5)-Ca_(0.4)MoO_4Eu_(0.1~3) cause the host crystal orientation changed. The photoluminescent results show that the synthesized phosphor powders can be effectively excited at the wavelengths of 395 nm in ultraviolet light area and 464 nm in blue light area and 534 nm in green light area, and Strongly enhanced red emission of Eu~(3+)is obtained by adding Bi~(3+) instead of increasing the Eu~(3+) concentration. For a fixed Eu~(3+) concentration, there is an optimal Bi~(3+) concentration, at which the maximum luminescence intensity is achieved. The proposed explanation of these changes can not only be attributed to the energy transfer between Bi~(3+) and Eu~(3+) but also to the change in the symmetry of Eu~(3+) ions when doping Bi~(3+) into Sr_(0.5)Ca_(0.4)MoO_4Eu_(0.1)~3.