What Happens to MnO ₂ When It Comes in Contact with Zn ²⁺ ? An Electrochemical Study in Aid of Zn/MnO ₂ ‐Based Rechargeable Batteries

In the science and technology of electrochemical energy storage, different allotropes MnO2, fabricated with a variety methods, are assembled into electrodes, playing role cathode or ORR electrocatalyst. Often, MnO2-based cathodes combined Zn anodes types batteries, resulting in contact between MnO2 its reaction products, Zn2+. Awareness is growing that this interaction adversely affects functional performance but no definitive understanding has been reached issue. This study contributes, through measurements accompanied by microscopy Raman spectroscopy, to better way behaviour two technologically representative manganese dioxide - hydrothermally grown α-MnO2 electrodeposited γ-MnO2 (EDM) degraded when these materials exposed neutral alkaline aqueous solutions, containing Specifically, we highlighted irreversible changes response, can be interpreted phase-formation processes. Such result deactivation as electrocatalyst, both EDM zinc-ion battery (ZIB) cathodes. The electroactivity for ZIB operation restored if Mn2+ added electrolyte, because phase, active discharge, during charging. article protected copyright. All rights reserved.