Cross-linked carbon tube-MnO2 composite enables high-performance Zn ion batteries

Aqueous zinc-ion batteries (ZIBs) have emerged as promising energy storage devices due to their high safety, abundant, and environmental friendliness. However, the development of high-performance cathode materials remains a significant challenge. In this work, we report an accessible manganese (II) oxide coated carbon nanotube (MnO 2 /CNT) composite prepared via a facile ball milling method, which significantly enhances the electrochemical performance of ZIBs. The optimal MnO 2 /CNT composite exhibits a high specific capacity of 388.5 mAh g −1 at 0.1 A g −1 , and long-term cycling stability with 67.51 % capacity retention at 1 A g −1 after 500 cycles. The improved performance is attributed to the enhanced electrical conductivity, optimized Zn 2+ diffusion kinetics, and stable structural integrity of the MnO 2 /CNT composite. This study provides a simple and scalable approach to designing high-performance cathode materials for next-generation ZIBs.