文献类型：期刊文献

英文题名：Reactivating ZnMn3O7(H2O)2 deposition by higher potential towards ultra-high capacity in β-MnO2 based zinc-ion batteries

作者：Wan, Zhanxun[1];Geng, Hao[2];Yuan, Yuan[3,4];Cao, Huiliang[1,3,4]

机构：[1]East China Univ Sci & Technol, Sch Mat Sci & Engn, Interfacial Electrochem & Biomat, Shanghai 200237, Peoples R China;[2]Changzhou Univ, Adv Carbon Mat Res Ctr, Sch Mat Sci & Engn, Changzhou 213164, Peoples R China;[3]East China Univ Sci & Technol, Key Lab Ultrafine Mat, Minist Educ, Shanghai 200237, Peoples R China;[4]East China Univ Sci & Technol, Engn Res Ctr Biomed Mat, Minist Educ, Shanghai 200237, Peoples R China

年份：2025

卷号：639

外文期刊名：JOURNAL OF POWER SOURCES

收录：;EI(收录号：20251017988790);WOS:【SCI-EXPANDED(收录号:WOS:001441587500001)】；

基金：This work was jointly supported by grants from the National Natural Science Foundation of China (32271399 and 31870945) , the Natural Science Foundation of Shanghai (21ZR1415700) , and the Shanghai Committee of Science and Technology (23S31901700) .

语种：英文

外文关键词：Aqueous Zn||MnO2 batteries; Mn2+-poor zone; Electrochemical behavior

摘要：Weakly acidic aqueous Zn||MnO2 batteries have garnered significant interest due to their impressive electrochemical performance and safety features. They exhibit considerable potential for applications in wearable health monitoring devices and implantable medical devices. However, the unclear energy storage mechanism and electrochemical behavior hinder further enhancements in battery performance. In this study, the phase evolution process on the beta-MnO2 electrode is systematically investigated, revealing that electrochemically active ZnMn3O7(H2O)2 nanosheets with low crystallinity are deposited during charging. During discharging, both the dissolution of the nanosheets (reversible) and the dissolution of pristine (3-MnO2 (irreversible) occur. The irreversible dissolution of the pristine active material may induce changes in the internal structure and composition of the electrode, potentially enhancing its conductivity and electron transfer rate. Furthermore, a compensatory effect resulting from the directional and localized transfer of Mn2+ from the bulk electrolyte to the Mn2+-poor zone near the electrode, induced by high potential, is proposed. This effect reactivates the deposition of ZnMn3O7(H2O)2 nanosheets on the electrode, leading to an ultra-high apparent specific capacity of 817.93 mAh center dot g-1. These findings provide new insights into the energy storage mechanism of (3-MnO2 cathodes, potentially advancing the field of high-performance Zn||MnO2 batteries.