查看文章

Layered MnO₂ is very attractive cathode material for zinc-ion battery (ZIB) due to its large interlayer distance, high discharge capacity, low cost, and environmental benignity. However, layered MnO₂ exhibits capacity fading. Therefore, detailed studies of the structural transformation and electrochemical mechanism of layered MnO₂ during cycling are urgently required for performance improvement. In this contribution, we have utilized in situ synchrotron, ex situ X-ray diffraction, and ex situ synchrotron X-ray absorption spectroscopy analyses in order to evaluate the structural transformation of a layered MnO₂ during Zn-ion insertion. We found that during initial cycles, the electrode was able to maintain its layered structure; however, after prolonged cycles, it completely transformed into an irreversible spinel structure. We also observed the manganese dissolution from the electrode into the electrolyte during continuous …