Facilitating the Electrochemical Oxidation of ZnS through Iodide Catalysis for Aqueous Zinc‐Sulfur Batteries

• Published in: Angewandte Chemie International Edition Vol. 63; no. 9; pp. e202316082 - n/a
• Main Authors: Hei, Peng, Sai, Ya, Liu, Chang, Li, Wenjie, Wang, Jing, Sun, Xiaoqi, Song, Yu, Liu, Xiao‐Xia
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 26.02.2024
• Edition: International ed. in English
• Subjects: Aqueous Battery; Aqueous solutions; Bonding strength; Catalysis; Catalysts; Catalytic converters; Catalytic Effect; Electrochemical oxidation; Electrochemistry; High Performance; Iodides; I− Additive; Mechanism Study; Nanoparticles; Oxidation; Sulfur; Zinc; Zinc sulfide; I− Additive; Catalytic Effect; Mechanism Study; Aqueous Battery; High Performance
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.202316082

Aqueous zinc‐sulfur (Zn‐S) batteries show great potential for unlocking high energy and safety aqueous batteries. Yet, the sluggish kinetic and poor redox reversibility of the sulfur conversion reaction in aqueous solution challenge the development of Zn‐S batteries. Here, we fabricate a high‐performance Zn‐S battery using highly water‐soluble ZnI2 as an effective catalyst. In situ experimental characterizations and theoretical calculations reveal that the strong interaction between I− and the ZnS nanoparticles (discharge product) leads to the atomic rearrangement of ZnS, weakening the Zn‐S bonding, and thus facilitating the electrochemical oxidation reaction of ZnS to S. The aqueous Zn‐S battery exhibited a high energy density of 742 Wh kg(sulfur)−1 at the power density of 210.8 W kg(sulfur)−1 and good cycling stability over 550 cycles. Our findings provide new insights about the iodide catalytic effect for cathode conversion reaction in Zn‐S batteries, which is conducive to promoting the future development of high‐performance aqueous batteries. The reversible conversion of sulfur cathodes in aqueous Zn‐S batteries is realized by applying the highly water‐soluble ZnI2 catalyst. Experimental and computational results indicate that abundant iodide ions adsorbed on ZnS nanoparticles surface regulate the d‐band center of Zn, leading to atomic rearrangements, and therefore promoting the electro‐oxidation of ZnS to S.