Blue long-lasting phosphorescence of Ti-doped BaZrO3 perovskites

Long-lasting phosphorescence was observed from Ti-doped BaZrO3 perovskite synthesized by a solid-state reaction. The phosphorescence color is blue and the phosphorescence can still be seen with the naked eye in the dark for 30 min or more after stopping UV irradiation. By the measurements of electron spin resonance (ESR) spectra, it was confirmed that F+ center and Zr3+ exist in non-luminescent undoped BaZrO3 and their concentrations decreased with the additive amount of TiO2. It is expected that the luminescence center is FA center composed of Ti3+ and F+ center.