The criterion of effective traps and full spectrum persistent luminescence in phosphors with dual luminescent center

Persistent luminescence (PersL) materials have emerged as an outstanding optical media with versatile applications in data storage, anti-counterfeiting, and beyond. However, their practical implementation is critically hindered by insufficient PersL intensity, a challenge fundamentally rooted in the incomplete understanding of trapping mechanisms. Here, we developed Tb 3+ -activated Ga 4 GeO 8 phosphors with rational defect manipulation via Ln 3+ (Ln = Pr, Eu, Ce, Er) co-doping strategies. Especially, when Eu 3+ /Er 3+ are introduced as lattice distortion agents into Tb 3+ -doped Ga 4 GeO 8 , the phosphors demonstrate dual-band PersL including blue-green PersL from Tb 3+ 5 D 4 → 7 F J transitions (492–620 nm) and red-NIR PersL emission (715 nm) originating from oxygen defect levels. Through systematic exploration of the PersL mechanism, we propose a criterion for effective trapping: stabilizing V O •• defect energy levels by replacing matrix cations with less electronegative species (e.g., Eu 3+ , Er 3+ ), which suppresses non-radiative V O defect states. This study establishes design guidelines for the rational development of high-performance PersL materials.