A Reversible Six‐Electron Transfer Cathode for Advanced Aqueous Zinc Batteries
Zichao Yan, Junwei Li, Hongguang Liu, Hui Zhang, Shibo Xi, Zhiqiang Zhu
Abstract
Abstract The electrochemical reactions for the storage of Zn 2+ while embracing more electron transfer is a foundation of the future high‐energy aqueous zinc batteries. Herein, we report a six‐electron transfer electrochemistry of nano‐sized TeO 2 /C (n‐TeO 2 /C) cathode by facilitating the reversible conversion of TeO 2 ↔Te and Te↔ZnTe. Benefitting from the integrated conductive nanostructure and the proton‐rich environment in providing optimized electrochemical kinetics (facilitated Zn 2+ uptake and high electronic conductivity) and feasible thermodynamic process (low Gibbs free energy change), the as‐prepared n‐TeO 2 /C with stable cycling performance exhibits a superior reversible capacity of over 800 mAh g −1 at 0.1 A g −1 . A precise understanding of the reaction mechanism via ex situ and in situ characterizations presents that the reversible six‐electron transfer reaction is proton‐dependent, and a proton generating and consuming mechanism of three‐phase conversion n‐TeO 2 /C in the weakly acidic electrolyte is thoroughly revealed.