Red to near-infrared persistent luminescence in transition metal ion activated phosphors

Abstract

Red-to-near infrared persistent phosphors have attracted great attention because they are promising candidates for in vivo imaging. However, for most of the persistent phosphors that are activated only by ultraviolet (UV) light, the detection time is limited because persistent luminescence decays with time and UV excitation cannot be repeated due to the opacity of living tissues to UV radiation. Therefore, we have developed persistent phosphors with perovskite and garnet structures, which show 1) persistent luminescence at an optimum wavelength with high transparency for living tissue, 2) with brighter and longer persistent luminescence, and 3) with an additional function leading to long-term in vivo imaging capability.