Fabrication of N-doped carbon-coated MnO/ZnMn2O4 cathode materials for high-capacity aqueous zinc-ion batteries.

Abstract

Rechargeable aqueous zinc-ion batteries (ZIBs) are highly promising energy storage devices due to their advantages of high energy density, low cost, environmental friendliness, and excellent safety. Investigation of advanced cathode materials featuring high capacity is desired for their applications in high-capacity ZIBs. In this study, a porous N-doped carbon-coated manganese oxide/zinc manganate (MZM@N-C) composite was successfully prepared as an advanced cathode material for aqueous ZIBs. The MZM@N-C cathode demonstrated a superior specific capacity of 772.8 mA h g-1 at 50 mA g-1 and maintained a high specific capacity of 205 mA h g-1 after 300 cycles at a high current density of 500 mA g-1. As compared to the unmodified MnOx cathode, MZM@N-C has a higher reversible capacity and cycling stability which could be assigned to the robust one-dimensional (1D) structure and the synergistic effect of MZM@N-C, providing instructive insight into the design of high-capacity manganese-based cathodes for rechargeable aqueous ZIBs. Furthermore, a soft-pack battery was assembled using the MZM@N-C cathode, demonstrating its potential applications in various devices.