Ecofriendly and low-cost high-entropy sulfides with high thermal stability and ZT > 1 via entropy engineering and anion compensation

• Published in: Nano energy 2024-12, Vol.131, p.110288, Article 110288
• Main Authors: Li, Suwei, Zhang, Ruizhi, Chen, Kan, Reece, Michael J.
• Format: Article
• Language: English
• Subjects: Anion compensation; Copper-based sulfides; High entropy; Thermal stability; Thermoelectric
• ISSN: 2211-2855
• DOI: 10.1016/j.nanoen.2024.110288

The thermoelectric performance and thermal stability of high-entropy sulfides (Cu7Mg2Sn2ZnGeS13, Cu5MgSnZnSiS9, and Cu7Mg2Sn2ZnSiS13) were studied and compared with copper-based monosulfides (Cu2S) and binary sulfides (Cu12Sb4S13). High-entropy sulfides exhibit superior thermal stability, characterized by higher decomposition onset temperatures and minimal weight loss, maintaining their structural stability up to 750 ℃. Cu7Mg2Sn2ZnSiS13 demonstrates a peak ZT of 0.52 at 500 ℃. Further optimization through sulfur compensation (Cu7Mg2Sn2ZnSiS13.5) results in a 200 % improvement of the peak ZT value to 1.12 at 550 ℃, which is comparable to other pristine copper-based sulfides, while being more eco-friendly and cost-effective. Entropy engineering provides a new way to improve the inherent thermal and structural stability of sulfides and can also optimize their thermoelectric performance using non-toxic and earth abundant cation elements. [Display omitted] •High entropy sulfides with wurtzite structure are designed using a data driven approach.•Single-phase high-entropy sulfides are synthesized using a scalable processing route using eco-friendly, earth-abundant elements.•Enhanced thermal stability of sulfides is achieved through entropy engineering.•Anion compensation leads to a peak ZT of 1.12 at 550 ℃.