Long Wavelength Extension of the Excitation Band of LiEuMo[sub 2]O[sub 8] Phosphor with Bi[sup 3+] Doping

Bi-doped red phosphor series were prepared by solid-state reactions which present bright red luminescence dominated by a transition of . With doping, the excitation bands of the phosphors extend to longer wavelength (from ), and the excitation efficiency for optimized content is dramatically increased, which favors the phosphors for the white-light ultraviolet light emitting diode applications. The luminescent model for the phosphors studied in this work is proposed. Because the 6p level of is immerged in the conduction band (CB), the excitation of is overlapped by the excitation , which results in extension of the excitation band. The absorbed energy by the excitation can be effectively transferred to , but the emission of disappears.