Luminescence quenching properties of Sr2Ga2GeO7: Pr3+ with and without traps participation

Highlights: • The thermal stability mechanism of Sr₂Ga₂GeO₇: Pr³⁺ needs to be further studied. • The introducing of co-solvents changes defect states structure. • The thermal stability of ¹D₂→³H₄ and ³P₀→³H₄ levels is relative to IVCT and traps. -- Abstract: Thermal quenching has been extensively regarded as one of the most significant challenges that limits the application of phosphors in today's world. Further effort is urgently required to understand the mechanism of thermal stability for achieving the improved performance of these phosphors. Sr₂Ga₂GeO₇: Pr³⁺ has been synthesized by the conventional high temperature solid state reaction. A dominant green emitting is presented for the partial energy transition quenching process of the ³P₀→³H₄ emission. The defect states structure is improved via the introducing of co-solvents, and the thermal stability of ¹D₂→³H₄ and ³P₀→³H₄ levels can be further adjusted. The intervalence charge transfer (IVCT) and traps are introduced to explain the luminescence quenching properties of Sr₂Ga₂GeO₇: Pr³⁺. The synergy of various models will provide a new idea for improving the luminescence stability of phosphors in the future.