Strategic vacancy engineering advances record-high ductile AgCu(Te, Se, S) thermoelectrics

作者：Nan‐Hai Li, Xiao‐Lei Shi, Siqi Liu, Meng Li, Tianyi Cao, Min Zhang, Wanyu Lyu, Wei‐Di Liu, Dongchen Qi, Zhi‐Gang Chen · 发表于：Nature Communications · 年份：2025 · DOI：10.1038/s41467-025-58104-x · 被引用次数：27 · 研究领域：Advanced Thermoelectric Materials and Devices、Chalcogenide Semiconductor Thin Films、Thermal Radiation and Cooling Technologies

AgCu(Te, Se, S) alloys, as one of the rare p-type plastic inorganic thermoelectrics, are receiving striking attention for their application foreground in high-performing flexible thermoelectric generators. However, strategies to enhance their thermoelectric performance while maintaining exceptional plasticity remain largely unexplored. Here, we introduce a strategic vacancy-engineering approach to address this challenge. Using computational design as a guide, we carefully tune the cation vacancy concentration to optimize hole carrier concentration, achieving impressive ZTs of ~0.62 at 300 K and ~0.83 at 343 K in (AgCu)0.998Te0.8Se0.1S0.1, ranking among the highest in this class of material. Importantly, numerous diffuse Ag-S bonds combined with amorphous phase introdeuced by vacancy engineering ensure that (AgCu)0.998Te0.8Se0.1S0.1 retains high plasticity while having high performance. A novel flexible thermoelectric device, comprising ductile p-type (AgCu)0.998Te0.8Se0.1S0.1 and n-type commercial Bi2Te3, achieves an impressive power density of ~126 μW cm−2 under 25 K temperature difference, demonstrating significant application prospects for wearable electronics. The authors report a vacancy engineering method to simultaneously optimize carrier concentration and maintain high plasticity, achieving a nearly 10% strain in three-point bending tests and a high ZT of ~0.83 at 343 K in (AgCu)0.998Te0.8Se0.1S0.1.