In Situ Converted Carbon-Coated MnO for Aqueous Zinc-Ion Batteries

Manganese-based materials have emerged as the most widely used cathode candidates for aqueous zinc-ion batteries, thus gaining extensive attention in related research fields. Nevertheless, it still faces the problems of the dissolution of Mn 2+ in the charge−discharge cycles, the facile structural collapse of crystals, and the low kinetic performance of Zn 2+ migration. Herein, glucose was used as the carbon source to coat the MnO composite for zinc-ion batteries. The calcination temperatures are investigated to adjust the carbon layer and graphitization degree. This approach effectively inhibits manganese dissolution and boosts the electrochemical performance. The optimized MnO@C-500 sample presented a remarkable specific capacity of 268.5 mAh g −1 at 100 mA g −1 and maintained a capacity of 193.7 mAh g −1 after 200 cycles at 200 mA g −1 . The introduced carbon coating effectively improves the electrical conductivity and accelerates the electrochemical kinetics of the electrode.