Near ultraviolet excitable cyan-green phosphors of BaLaAlScO:Ce and BaLaAlScO:Ce,Tb: investigations on the crystal structure, site assignment of Ce and Tb ions, and an energy transfer process from Ce to Tb.

An energy transfer from Ce to Tb is feasible in energy transition processes for the development of optical devices, especially phosphor-converted white LEDs (pc-wLEDs). Most of the energy transfer phosphors co-doped with Ce and Tb, unfortunately, have weak absorption under a near-ultraviolet light of around 405 nm and blue light excitation, making them incapable for use as near ultraviolet or blue LEDs. In this study, novel energy transfer luminescent materials, BaLaAlScO:Ce,Tb, isostructural with existing BaLa(Al,Fe)O, were successfully synthesized through a conventional solid-state reaction as a single phase.