Premium
Synergistic Effect between S and Se Enhancing the Electrochemical Behavior of Se x S y in Aqueous Zn Metal Batteries
Author(s) -
Li Wei,
Ma Yongsong,
Li Peng,
Jing Xiaoyun,
Jiang Kai,
Wang Dihua
Publication year - 2021
Publication title -
advanced functional materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.069
H-Index - 322
eISSN - 1616-3028
pISSN - 1616-301X
DOI - 10.1002/adfm.202101237
Subject(s) - materials science , electrochemistry , aqueous solution , cathode , reactivity (psychology) , metal , chemical engineering , electrode , metallurgy , chemistry , medicine , alternative medicine , pathology , engineering
Developing high‐capacity conversional cathode materials for aqueous Zn batteries is promising to improve their energy densities but challenging as well. In this work, three kinds of selenium–sulfur solid solutions and their composites (denoted as SeS 14 @ 3D‐NPCF, SeS 5.76 @ 3D‐NPCF, and SeS 2.46 @ 3D‐NPCF) are proposed and systematically investigated. Due to the introduction of Se and its synergistic effect with S, their physical and electrochemical properties are manipulated; in particular, by optimizing the Se content in these composites, SeS 5.76 @ 3D‐NPCF shows a capacity of 1222 mAh g −1 and flat plateau of 0.71 V at 0.2 A g −1 , reaching an ultrahigh energy density of 867.6 Wh kg −1 (based on SeS 5.76 ), superior rate capacity of 713 mAh g −1 at 5 A g −1 , and stable cycling of 75% capacity retention after 500 cycles. In addition, the Zn storage kinetics is determined by the discharge process, during which SeS 5.76 @ 3D‐NPCF is converted into ZnSe and ZnS. More importantly, theoretical calculations reveal that Se can tailor the electron density difference, band structure, and reaction energy of S, which increase its conductivity and reactivity to facilitate the electrochemical reaction with Zn. This work explores high performance conversional cathode materials for aqueous Zn metal batteries and presents an effective strategy to modify their intrinsic properties.