Abstract
Aqueous rechargeable Zinc (Zn) batteries incorporating MnO2 cathodes possess favorable sustainability properties and are being considered for low-cost, high-safety energy storage. However, unstable electrode structures and unclear charge storage mechanisms limit their development. Here, advanced transmission electron microscopy, electrochemical analysis, and theoretical calculations are utilized to study the working mechanisms of a Zn/MnO2 battery with a Co2+ -stabilized, tunnel-structured α-MnO2 cathode (Cox MnO2 ). It is shown that Co2+ can be pre-intercalated into α-MnO2 and occupy the (2×2) tunnel structure, which improves the structural stability of MnO2 , facilitates the proton diffusion and Zn2+ adsorption on the MnO2 surface upon battery cycling. It is further revealed that for the MnO2 cathode, the charge storage reaction proceeds mainly by proton intercalation with the formation of α-Hy Cox MnO2 , and that the anode design (with or without Zn metal) affects the surface adsorption of by-product Zn4 SO4 (OH)6 ·nH2 O on MnO2 surface. This work advances the fundamental understanding of rechargeable Zn batteries and also sheds light on efficient electrode modifications toward performance enhancement.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.