Optically functional zeolites: Evaluation of UV and VUV stimulated photoluminescence properties of Ce3+- and Tb3+-doped zeolite X

The optical properties of Tb3+/Ce3+ doped zeolites;are elucidated with emph asis on ultraviolet (UV) and vacuum ultraviolet (VUV) excitation and lumine scence. Ce3+ sensitized Tb3+ emission with quantum yields of 85 % may be ob tained at 330 nm excitation. Low absorptivity at 254 nm due to low Ce3+ con centrations or low Ce3+/Tb3+ ratios, which are required for the suppression of UV components, restricts their applicability as phosphors for Hg-based discharges, e.g., in conventional fluorescent lamps. Near band edge excitat ion at 172 nm revealed an immediate quantum yield of 50 % enabled by a zeol ite --> Ce3+ (5d(1)) --> Tb3+ (4f(7)5d(1)) energy transfer channel, which m ay be exploited for the down-conversion of the Xe-2 excimer emission.