Deep-red persistent luminescence in Cr3+-doped LaAlO3perovskite phosphor for in vivo imaging

We report deep-red long-lasting persistent luminescence in Cr3+-doped LaAlO3 perovskite phosphor synthesized by solid-state reaction. The LaAlO3:Cr3+ sample showed persistent luminescence peaking at a very long wavelength of 734 nm due to Cr3+:2E → 4A2 transition after ultraviolet excitation. The Sm3+ ion was found to be a good codopant for increasing the persistent luminescence intensity more than 35-fold. For the Cr3+–Sm3+-codoped LaAlO3 sample, the radiance of persistent luminescence in mW sr−1 m−2 unit was higher than or comparable to that of ZnGa2O4:Cr3+ phosphor, which is a candidate phosphor with a peak luminescence at 694 nm for in vivo imaging application.