Enhanced High-Performance Aqueous Zinc Ion Batteries with Copper-Doped α-MnO₂ Nanosheets Cathodes

Abstract

Aqueous zinc ion batteries (ZIBs) have garnered considerable interest due to their eco-friendly nature, cost-efficiency, and remarkable safety features, making them a compelling contender for next-generation energy storage systems. Within the extensive array of cathode materials investigated for ZIBs, manganese-based materials stand out for their notable attributes, including low toxicity and high voltage. Nevertheless, their widespread application has been impeded by challenges related to poor cycling stability, low electrical conductivity, and intricate energy storage mechanisms. In this study, we present a novel approach to address these challenges by synthesizing copper-doped α -MnO 2 nanosheets through a facile hydrothermal route. The resulting cathode material exhibits remarkable electrochemical properties when integrated into Zn/MnO 2 batteries. At a low current density of 0.1 Ag −1 , these batteries demonstrate an impressive reversible capacity of 445 mAh g −1 , signifying their substantial energy storage capabilities. Furthermore, even when subjected to a demanding high current density of 1 Ag −1 , they exhibit an exceptional cycling life of up to 1000 cycles, highlighting the enhanced durability of the copper-doped α -MnO 2 nanowire cathode. This research paves the way for the development of high-performance Zn/MnO 2 batteries, leveraging the advantages of manganese-based cathode materials while mitigating their inherent limitations. These findings represent a significant step forward in the development of environmentally sustainable and economically viable energy storage solutions, offering hope for a more sustainable energy future.