Abstract Near-infrared emitting persistent luminescent materials have potential applications in night-vision surveillance and medical imaging. Rational designing of the phosphor composition is of great importance for achieving sufficiently strong and long-lasting persistent luminescence. Herein, a series of MgGa2O4:Cr3+ phosphors with variable concentrations of Cr3+ were prepared via solid state reaction. MgGa2O4:Cr3+ exhibits strong emission in the range from 650 to 800 nm and three excitation bands centered at 275, 420 and 576 nm. With appropriate selection of codopant M (M = Al3+, Si4+, Ge4+ or Sn4+), the MgGa2O4:Cr3+, M phosphor presents remarkably enhanced persistent luminescence. Moreover, the trap distributions were tuned and the number of traps was greatly increased via codoping. In particular, MgGa2O4:Cr3+, Si4+ shows more than 7 h of persistent near-infrared light emission before the intensity drops to 5 × 10−4 mWsr−1m−2. Codoping with appropriate ions provides a good example in optimization and development of persistent luminescent phosphors for potential bioimaging applications.

中文翻译：

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通过共掺杂增强 MgGa2O4:Cr3+ 的近红外持续发光

摘要 近红外发光材料在夜视监控和医学成像方面具有潜在的应用价值。荧光粉成分的合理设计对于实现足够强和持久的持续发光具有重要意义。在此，通过固态反应制备了一系列具有不同浓度 Cr3+ 的 MgGa2O4:Cr3+ 荧光粉。MgGa2O4:Cr3+ 在 650 到 800 nm 范围内表现出强发射，三个激发带集中在 275、420 ​​和 576 nm。With appropriate selection of codopant M (M = Al3+, Si4+, Ge4+ or Sn4+), the MgGa2O4:Cr3+, M phosphor presents remarkably enhanced persistent luminescence. 此外，陷阱分布被调整，陷阱的数量通过共掺杂大大增加。特别是 MgGa2O4:Cr3+，Si4+ 在强度下降到 5 × 10−4 mWsr−1m−2 之前显示出超过 7 小时的持续近红外光发射。用合适的离子共掺杂为优化和开发用于潜在生物成像应用的持久发光磷光体提供了一个很好的例子。