Nonequivalent Substitution and Charge-Induced Emitter-Migration Design of Tuning Spectral and Duration Properties of NaCa2GeO4F:Mn2+ Persistent Luminescent Phosphor

详细信息    查看全文

• 作者：Zhenbin Wang ; Lin Feng ; Jiachi Zhang ; Zhipeng Ci ; Zhiya Zhang ; Yuhua Wang
• 刊名：Inorganic Chemistry
• 出版年：2016
• 出版时间：August 15, 2016
• 年：2016
• 卷：55
• 期：16
• 页码：7988-7996
• 全文大小：805K
• 年卷期：0
• ISSN：1520-510X

文摘

We combine nonequivalent substitution and charge-induced emitter-migration approaches and design an efficient method to optionally tune the spectral and duration properties of NaCa₂GeO₄F:Mn²⁺ phosphor. A series of representative codopants have been investigated in detail and classified into two categories: R_A (R_A = Li⁺, Al³⁺, N^3–, Ga³⁺, B³⁺) and R_B (R_B = Mg²⁺, F^–, Bi³⁺, Zn²⁺, Cd²⁺, Sc³⁺, Tm³⁺). Results reveal that the nonequivalent substitution of R_A codopants would induce foreign negative defects and stabilize Mn²⁺ emitters at octahedral Na/Ca sites for red emission. In constrast, the R_B codopants would generate foreign positive defects and make Mn²⁺ emitters migrate to tetrahedral Ge⁴⁺ sites for green-yellow emission. At the same time, the R_A codopants are in favor of the generation of intrinsic positive traps with shallow trap depth and thus efficiently improve the duration properties of phosphors. On the basis of the experimental results, a possible nonequivalent substitution and charge-induced emitter-migration model has been proposed, and we can optionally tune the spectral (568 ↔ 627 nm) and the duration (minutes to more than 6 h) properties according to this model.