Abstract The composition and tunable luminescence properties of garnet phosphors are flexible because of their unique A3B2C3O12 structure. Garnet phosphors with tailored luminescence properties can be designed by varying in the A, B, and C cation sublattices. In this research, the self-activated long-persistent phosphor (LPP) Na2CaSn2Ge3O12 (NCSG) was successfully synthesized by a solid-state method. A series of dopants (Mn2+, Pr3+, Tb3+, and Dy3+) were selected as single-component emitters to tailor the emission color of the NCSG phosphor. NCSG emits in yellow at ~ 560 nm and in the near-infrared at ~ 790 nm with long-persistent luminescence (PersL). By doping with these ions, the PersL of the NCSG was significantly improved, and various colors covering the entire visible region from violet to the near-infrared were obtained. The trap types and depths were examined by electron paramagnetic resonance (EPR) and the thermo-luminescence (TL) glow curves. The EPR signals revealed that oxygen vacancies are the trap centers. The TL glow curves showed that the intrinsic and extrinsic luminescence centers both act as charge carrier recombination centers. Furthermore, the PersL mechanism of the NCSG and NCSG:R (R = Mn2+, Pr3+, Tb3+ and Dy3+) phosphors was discussed in detail. The strategies employed in this work can be an effective way to fabricate new multi-wavelength, garnet-based LPPs with potential applications.

中文翻译：

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自激活荧光粉：Na 2 CaSn 2 Ge 3 O 12 的可调全可见区颜色发射，增强发射强度和持久性能

摘要 石榴石荧光粉由于其独特的A3B2C3O12 结构，其组成和可调发光特性是灵活的。可以通过改变 A、B 和 C 阳离子亚晶格来设计具有定制发光特性的石榴石磷光体。本研究通过固态方法成功合成了自激活长余辉荧光粉（LPP）Na2CaSn2Ge3O12（NCSG）。选择了一系列掺杂剂（Mn2+、Pr3+、Tb3+ 和 Dy3+）作为单组分发射器来定制 NCSG 荧光粉的发射颜色。NCSG 在 ~ 560 nm 处发出黄色光，在 ~ 790 nm 处发出近红外光，具有长余辉发光 (PersL)。通过掺杂这些离子，NCSG 的 PersL 得到了显着改善，并且获得了覆盖从紫色到近红外整个可见光区域的各种颜色。通过电子顺磁共振 (EPR) 和热发光 (TL) 辉光曲线检查陷阱类型和深度。EPR 信号显示氧空位是陷阱中心。TL 发光曲线表明内在和外在发光中心都作为电荷载流子复合中心。此外，详细讨论了 NCSG 和 NCSG:R（R = Mn2+、Pr3+、Tb3+ 和 Dy3+）荧光粉的 PersL 机制。这项工作中采用的策略可以成为制造具有潜在应用的新型多波长、基于石榴石的 LPP 的有效方法。TL 发光曲线表明内在和外在发光中心都作为电荷载流子复合中心。此外，详细讨论了 NCSG 和 NCSG:R（R = Mn2+、Pr3+、Tb3+ 和 Dy3+）荧光粉的 PersL 机制。这项工作中采用的策略可以成为制造具有潜在应用的新型多波长、基于石榴石的 LPP 的有效方法。TL 发光曲线表明内在和外在发光中心都作为电荷载流子复合中心。此外，详细讨论了 NCSG 和 NCSG:R（R = Mn2+、Pr3+、Tb3+ 和 Dy3+）荧光粉的 PersL 机制。这项工作中采用的策略可以成为制造具有潜在应用的新型多波长、基于石榴石的 LPP 的有效方法。