A multicolor persistent luminescent phosphor Sr ₂ Ga ₂ GeO ₇ :Pr ³⁺ for dynamic anticounterfeiting

Abstract

Abstract Persistent luminescence (PersL) phosphor is a glow‐in‐the‐dark material that has been widely applied. Here, we report a multicolor PersL phosphor Sr 2 Ga 2 GeO 7 :Pr 3+ . The PersL color can be tuned from deep red to blue. It reveals that the luminescent color modulation of the Sr 2 Ga 2 GeO 7 :Pr 3+ phosphor is essentially associated with the cross‐relaxation effect of Pr 3+ in the host with low‐phonon assistance energy. The PersL lifetime of the multicolor phosphors can be also tuned. Based on the unique features of Sr 2 Ga 2 GeO 7 :Pr 3+ phosphor, some simple PersL images are fabricated to emit dynamic multicolor information, and it shows that the PersL image even depicts dynamic multicolor anticounterfeiting.