Electrodeposited Manganese Oxide on Carbon Paper for Zinc‐Ion Battery Cathodes

Abstract

Nano‐crystalline, flake‐like Mn oxide was electrodeposited onto carbon paper (CP) using a pulsed electrodeposition technique. The electrodeposited Mn oxide was identified as Mn3O4 through a combination of X‐ray photoelectron spectroscopy (XPS), X‐ray diffraction (XRD), and Raman spectroscopy. The Mn3O4 on CP was used as a cathode for Zn‐ion batteries (ZIBs) and showed excellent cyclability at a current density of 1 A g−1 with a capacity retention of 139 % after 200 cycles. Electron microscopy was used to characterize the microstructural changes of the cathode at various stages during discharge/charge cycling. This work in combination with the electrochemical results suggests a two‐step reaction mechanism involving both intercalation and conversion reactions. The results demonstrate that electrodeposition of the cathode material is a simple, quick, and potentially scalable electrode synthesis method for producing high performing Zn‐ion electrodes without the use of binders or other additives.

Scientific Challenges for the Implementation of Zn-Ion Batteries

“…20 Thus, soluble Mn 2+ salts are typically employed as electrolyte additives to inhibit this dissolution and stabilize cycle life. However, electrolytes containing Mn 2+ allow for electrodeposition of MnO 2 onto the electrode surface, 73 which risks diminishing the quality of the cathode material and/or passivating the electrode-electrolyte interface. Because a delicate balance exists between Mn 2+ dissolution into the electrolyte and MnO 2 deposition onto the electrode surface, future research is urgently required to provide crucial insight into this equilibrium process.…”

Recent Development of Mn‐based Oxides as Zinc‐Ion Battery Cathode

“…Perhaps the most well‐studied ZIB cathode materials are Mn‐based oxides [28–30] . This is due to the highly matured synthesis techniques reported for various Mn‐based oxides, economical aspects, and the various oxidation states of Mn [24,31–35] . As such, these factors have garnered increasing interest in the development of high‐performing Mn‐based oxides as ZIB cathode [36] .…”

Recent advances and perspectives on vanadium- and manganese-based cathode materials for aqueous zinc ion batteries

“…Only a few manganese oxides can be cathode materials for ZIBs [171]. Mn 3 O 4 is an important one, in which the valence of [180] with permission from Springer Verlag.…”