压力调控无铅钙钛矿Cs₃Cu₂Cl₅的光学性质研究

Study on the Optical Properties of Lead-Free Perovskite Cs₃Cu₂Cl₅ under Pressure Control

摘要: 无铅钙钛矿因其环境友好、储量丰富和独特的光物理性质而备受关注。本文采用金刚石对顶砧高压实验装置，结合原位荧光光谱表征技术，研究了Cs₃Cu₂Cl₅微晶材料在高压下的光致发光性质，并结合第一性原理密度泛函理论(DFT)计算来阐明电子能带结构性质。当压力从0 GPa增加到3.0 GPa时，发射峰蓝移。卸压发射峰红移。压力对电子–声子耦合强度的调控作用是产生压致荧光变色现象的原因。本文为理解铜基卤化物中的高压发光行为以及开发稳定型压力响应发光材料提供参考。

Abstract: Lead-free perovskites have attracted significant attention due to their environmental friendliness, abundant reserves and unique photophysical properties. In this study, a diamond anvil cell high-pressure experimental setup was used in conjunction with in situ fluorescence spectroscopy to investigate the photoluminescence properties of Cs₃Cu₂Cl₅ microcrystalline material under high pressure. Combined with first-principles density functional theory (DFT) calculations, the electronic band structure properties were clarified. When the pressure increased from 0 GPa to 3.0 GPa, the emission peak blueshifted. Upon depressurization, the emission peak redshifted. The modulatory effect of pressure on the strength of electron-phonon coupling is the cause of the pressure-induced fluorescence color-change phenomenon. This study provides insights into the high-pressure luminescence behavior in copper-based halides and serves as a reference for the development of stable, pressure-responsive luminescent materials.