Study on the High-Temperature and High-Pressure Electrical Properties of Copper Iodide with Sulfur Doping (CuI<sub>1-x</sub>S<sub>x</sub>) System

本研究通过高温高压法(2.0 GPa, 300℃)合成了硫掺杂碘化铜(CuI1-xSx, x = 0.0~0.1)材料，系统探究了硫掺杂对其电学性能的影响。采用X射线衍射(XRD)分析表明，硫掺杂导致晶格膨胀(低掺杂)或形成固溶体结构(高掺杂)。电学性能测试显示，当硫掺杂摩尔比为0.025时，样品表现出最优异的综合性能：电导率显著提升(达最高值1.25 × 10³ S·m−1)，功率因子(PF)达到最大值4.8 mW·m−1·K−1，相较于未掺杂样品提升近3倍。进一步分析表明，适量硫掺杂通过引入空穴机制增强了p型半导体特性，而过量掺杂(x > 0.050)则因载流子散射加剧导致性能下降。本研究揭示了硫掺杂对碘化铜电学性能的调控规律，为优化其热电应用提供了实验依据。In this study, sulfur-doped copper iodide (CuI1-xSx, x = 0.0~0.1) materials were synthesized by high-temperature and high-pressure method (2.0 GPa, 300˚C), and the influence of sulfur doping on their electrical properties was systematically investigated. X-ray diffraction (XRD) analysis indicated that sulfur doping led to lattice expansion (low doping) or the formation of a solid solution structure (high doping). Electrical property tests showed that when the sulfur doping molar ratio was 0.025, the sample exhibited the most excellent comprehensive performance: the electrical conductivity significantly increased (reaching the maximum value of 1.25 × 10³ S·m−1), and the power factor (PF) reached the maximum value of 4.8 mW·m−1·K−1, nearly three times higher than that of the undoped sample. Further analysis indicated that moderate sulfur doping enhanced the p-type semiconductor characteristics by introducing a hole mechanism, while excessive doping (x > 0.050) led to performance degradation due to increased carrier scattering. This study revealed the regulation law of sulfur doping on the electrical properties of copper iodide and provided experimental basis for optimizing its thermoelectric applications.