Abstract The features of IR luminescence of colloidal Ag 2 S QDs passivated with thioglycolic acid (Ag 2 S/TGA) under the formation of Ag 2 S/ZnS/TGA core/shell QDs are considered. A 4.5-fold increase in the quantum yield of recombination IR luminescence within the band with a peak at 960 nm (1.29 eV), full width at half maximum of 250 nm (0.34 eV), and the Stokes shift with respect to the exciton absorption of 0.6 eV was found. The increase in the IR luminescence intensity of Ag 2 S/ZnS/TGA QDs is accompanied by an increase in the average luminescence lifetime from 2.9 ns to 14.3 ns, which is explained as “healing” of surface trap states during the formation of the ZnS shell. For the first time, the enhancement of the luminescence intensity photodegradation (hereinafter referred to as fatigue) was found during the formation of the Ag 2 S/ZnS/TGA core/shell QDs. The luminescence fatigue is irreversible. We conclude that the initial stage of photolysis of the Ag 2 S core QDs under laser irradiation plays a key role. Low-atomic photolytic clusters of silver formed on the Ag 2 S core QDs act as luminescence quenching centers and do not reveal structural transformations into Ag 2 S, provided that the clusters are not in contact with TGA.

中文翻译：

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巯基乙酸封端的胶体 Ag2S/ZnS 核/壳量子点的发光

摘要 考虑了在Ag 2 S/ZnS/TGA核/壳QDs的形成下，巯基乙酸钝化的胶体Ag 2 S QDs的红外发光特征(Ag 2 S/TGA)。波段内复合红外发光的量子产率增加 4.5 倍，峰值为 960 nm (1.29 eV)，半峰全宽为 250 nm (0.34 eV)，斯托克斯位移相对于激子吸收发现了 0.6 eV。Ag 2 S/ZnS/TGA QDs IR 发光强度的增加伴随着平均发光寿命从 2.9 ns 增加到 14.3 ns，这被解释为 ZnS 形成过程中表面陷阱态的“愈合”壳。首次，在Ag 2 S/ZnS/TGA核/壳QDs的形成过程中发现了发光强度光降解（以下简称疲劳）的增强。发光疲劳是不可逆的。我们得出结论，Ag 2 S 核心量子点在激光照射下的初始光解阶段起着关键作用。在 Ag 2 S 核心 QD 上形成的低原子银光解簇充当发光猝灭中心，并且不会显示结构转变为 Ag 2 S，前提是这些簇不与 TGA 接触。