Achieving Luminescence of Sr₃Ga_1.98In_0.02Ge₄O₁₄:0.03Cr³⁺ via [In³⁺] Substitution [Ga³⁺] and Its Application to NIR <i>pc</i>-LED in Non-Destructive Testing

Abstract

Cr3+-doped Sr3Ga2Ge4O14:0.03Cr3+ (SGGO:0.03Cr3+) phosphor was synthesized via a high-temperature solid-phase method. Considering the tunable structure of SGGO, Ga3+ ions in the matrix were substituted with In3+ ions at a certain concentration. The tuned phosphor produced a red-shifted emission spectrum, with its luminescence intensity at 423 K maintained at 63% of that at room temperature; moreover, the internal quantum efficiency increased to 65.60%, and the external quantum efficiency correspondingly increased to 21.94%. On this basis, SGIGO:0.03Cr3+ was encapsulated into a pc-LED, which was applied in non-destructive testing (NDT) experiments, successfully realizing the recognition of water and anhydrous ethanol, proving its potential application in the field of NDT.

Keywords

• Cr³⁺ doping
• cation substitution
• thermal stability
• luminous intensity