Crystallographic types depended energy storage mechanism for zinc storage

• Published in: Nano energy Vol. 125; p. 109524
• Main Authors: Zhu, Yirong, Zhong, Wenping, Chen, Wenhao, Hu, Zhongliang, Xie, Yujia, Deng, Wentao, Hou, Hongshuai, Zou, Guoqiang, Ji, Xiaobo
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.06.2024
• Subjects: Aqueous zinc-ion batteries; Cathode materials; Crystallographic types; Energy storage mechanism; MnS hollow microspheres; MnS hollow microspheres; Aqueous zinc-ion batteries; Energy storage mechanism; Cathode materials; Crystallographic types
• ISSN: 2211-2855
• DOI: 10.1016/j.nanoen.2024.109524

As a new type cathode material for aqueous zinc-ion batteries (ZIBs), manganese-based sulfides have gradually received researchers’ concern in recent years due to their lower electronegativity, higher electronic conductivity and better electrochemical activity compared with the corresponding manganese-based oxides. However, the revelation of energy storage mechanism for manganese-based sulfides is full of great challenges, which largely restricts their application. Herein, inspired by density functional theory calculations, we design and synthesize the γ-MnS and α-MnS hollow microspheres with different crystallographic types for the first time, delivering significantly different energy storage mechanisms of the two MnS electrodes. Impressively, the γ-MnS electrode can stably exist and store energy during the whole charging/discharging processes, while the α-MnS electrode first undergoes irreversible in situ oxidation to generate ZnMnO3/MnOx during the initial charging process, and then the reversible H+/Zn2+ co-insertion/extraction energy storage behavior occurs during the subsequent discharging/charging processes. This unique phase transition mechanism caused by in situ electrochemical oxidation enables the α-MnS electrode to achieve enhanced ion diffusion kinetics, thereby improving the rate capability and cyclic stability. This work not only enriches the energy storage mechanism of manganese-based sulfide cathodes, but also offers research ideas for the design and development of advanced manganese-based cathodes. [Display omitted] •The γ-MnS and α-MnS hollow microspheres with different crystallographic types are designed based on DFT calculations.•The crystallographic types significantly affect zinc storage performance and energy storage mechanisms.•The α-MnS electrode shows better rate performance and cycling stability.•The kinetic tests deeply elucidate enhanced kinetic behavior of the α-MnS electrode.•Ex situ tests elucidate significantly different energy storage mechanisms of the two MnS electrodes.