Key Words:-
Abstract:Monovalent anions, with relatively low charge density, exhibit weak bond energy with Zn2 ions, which facilitates the solubility of Zn salts and the regulation of solvation structures. In this study, zinc bis (aminosulfate) (Zn(NH2SO3)2) with a monovalent anion, NH2SO3- , was synthesized and dissolved in different ratios of dimethyl sulfoxide (DMSO) and H2O as electrolytes for Zn-ion batteries (ZIBs). From the perspective of game theory, the influences of DMSO and H2O on the solvation structure and electrochemical performance of the Zn(NH2SO3)2 based electrolytes has been meticulously discussed. Computations and spectra analysis indicate that DMSO molecules are reluctant to penetrate the primary solvation structure of Zn2 ions. Indeed, increasing DMSO in electrolytes can induce a transition from solvent-separated ion pairs (SSIP) to contact ion pairs (CIP), resulting in an enrichment of anions in the primary solvation structure. This alteration can significantly suppress parasitic reactions, enhance nucleation density, and refine the deposition morphology during the Zn plating process, leading to superior cyclic stability and high coulombic efficiency (CE) of Zn//Cu and Zn//Zn cells. However, the enrichment of anions in the primary solvation structure also inhibits the activity of Zn2 ions, amplifies the polarization effect, and engenders a sluggish ionization dynamics, resulting in the low energy conversion efficiency of the battery. These findings underscore the influence of the anion ratio within the primary solvation structure on electrochemical properties of electrolytes for ZIBs, which may be a pivotal determinant in the Zn deposition process. (c) 2025 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
Volume:104
Issue:-
Translation or Not:no