Intensive green emission of ZnAl_2O_4:Mn^2+under vacuum ultraviolet and low-voltage cathode ray excitation

A series of Zn(1-x)Mn(x)Al(2)O(4) (x=0.001∼0.08) phosphors were synthesized by a traditional solid-state reaction route. Their photoluminescence under vacuum ultraviolet (VUV, energy E>50000 cm(-1), wavelength λ<200 nm) and cathodoluminescence under low-voltage electron beam excitation were evaluated. The luminescence decays were also measured. The intense green emission was observed with a peak at about 510 nm upon 172/147 nm excitation. The luminescence of optimum phosphor Zn(0.99)Mn(0.01)Al(2)O(4) (ZAM) was compared with that of commercial green phosphor Zn(2)SiO(4):Mn(2+) (ZSM). The maximum emission intensity of ZAM is larger than that of ZSM under 172/147 nm and low-voltage electron beam excitation. The values of chromaticity coordinates reveal the phosphors can evidently enlarge the tricolor gamut. The results show that the ZnAl(2)O(4):Mn(2+) phosphors may be considered as candidates for Hg-free lamps, plasma flat backlights, and field emission backlights for liquid crystal displays.