Thermal-responsive dynamic color-tunable persistent luminescence from green to deep red for advanced anti-counterfeiting

• Thermal-responsive dynamic color-tunable persistent luminescence is revealed in a singly-phase ZnGa 2 O 4 :Cr 3+ ,Mn 2+ phosphor. • Color of the persistent luminescence varies from green (∼503 nm) to deep red (∼709 nm) in 315 ∼ 650 K. • A dual-traps electronic structure and the different photoluminescence features of the two emitters are responsible for the thermal-responsive property. • Application potential of this phosphor for advanced anti-counterfeiting is demonstrated. Color-tunable persistent luminescent materials that respond to external physical stimuli are fascinating but rarely reported, especially the dynamic ones. In this work, a dynamically color-tunable persistent luminescence by varying the ambient temperature is revealed in an all-inorganic singly-phase Cr 3+ , Mn 2+ co-doped zinc gallate spinel phosphor. The persistent luminescence shows dramatic color variation from green (∼503 nm) to deep red (∼709 nm) in 350 ∼ 650 K. The application potential of this phosphor for advanced anti-counterfeiting is verified by fabricating several multi-level anti-counterfeiting models, which work under both fluorescence and afterglow modes. Further, by detailed optical investigations and theoretical calculations, two factors are demonstrated to endow the persistent luminescence of the co-doped phosphor with temperature-dependent afterglow colors: the dual-traps electronic structure of the host and the different photoluminescence thermal quenching properties of the Cr 3+ /Mn 2+ emitters. This work reports the dynamic color-tunable persistent luminescence under different temperatures in Cr 3+ , Mn 2+ co-doped zinc gallate and provides a new perspective for the design of thermal-responsive dynamic optical materials for the application of advanced anti-counterfeiting.