Long-lasting near-infrared persistent luminescence from β-Ga2O3:Cr3+ nanowire assemblies

Near-infrared (NIR) persistent luminescent β-Ga2O3:Cr3+ nanowire assemblies were synthesized by a hydrothermal process followed by calcination. The phosphor exhibits more than 4 h afterglow in the wavelength range of 650–850 nm after ceasing the ultraviolet light (280–360 nm) irradiation. The trap structure and persistent luminescence mechanism were revealed by thermoluminescence measurement. The β-Ga2O3:Cr3+ nanowire assemblies may find applications as identification taggants in security and optical probes in bio-imaging.