Promising red phosphors LaNbO4:Eu3+, Bi3+ for LED solid-state lighting application

O6; La0.75NbO4:Eu3+0.25 and La0.65NbO4:Eu3+0.25,Bi3+0.10 phosphors were synthesized by solid-state reaction method,and their photoluminescence properties were discussed in detail.With the increased incorporation of the co-activator Bi3+,the charge transfer (CT) bands of Nb5+→O2- and Eu3+→O2- (-280 nm) weakened and a new and significant broad band Bi3+-O2- (-330 nm) appeared,while the peaks at 395 and 466 nm assigned to f-f transitions of Eu3+ was slightly changed.Compared with the commercial phosphor Y2O2S:0.05Eu3+,La0.75Nb5O4:Eu3+0.25 and La0.65Nb504:Eu3+0.25,Bi3+0.10 phosphors emit brighter red light at 615 nm with line spectra upon the excitation of near UV light (395 nm) and exhibited the Commission International d'Eclairage (CIE) chromaticity coordinates (x=0.658,y=0.342) and (x=0.657,y=0.342) that are closer to the standard of national television standard committee (NTSC).The results showed that La0.75Nb5O4:Eu3+0.25 and La0.65Nb5O4:Eu3+ 0.25,Bi3+0.10 phosphors might be as promising red phosphors for near UV InGaN-based LED solid-state lighting application.