Sulfur‐Doped Vanadium Oxide for High‐Performance and Stable Cathode Material of Zinc‐Ion Batteries

Abstract Vanadium oxides (V 2 O 5 ) are promising alternatives to the cathode for zinc‐ion batteries with multivalent electrons and layered structures that support reversible ion insertion‐extraction and provide higher theoretical capacity. However, they suffer from poor electronic conductivity, high material dissolution into electrolytes, and structural degradation, resulting in reduced capacity and shorter lifespans. Herein, the synthesized sulfur‐doped V 2 O 5 via a controlled calcination process to achieve high‐performance cathode materials. The optimized conditions lead to V 2 O 5 material with increased interlayer spacing, improved structural stability, and enhanced electronic conductivity. Sulfur doping introduces defect sites, which promotes faster Zn 2 ⁺ ion diffusion and improves charge transfer kinetics. These contribute to the excellent electrochemical performance of the S‐doped V 2 O 5 . As a result, it achieves a high specific capacity of 142.2 mAh g −1 and impressive long‐term stability over 5,000 cycles at a current density of 2 A g −1 . These findings suggest that S‐doped V 2 O 5 is a promising cathode material for high performance and stable zinc‐ion batteries and can be an alternative cathode material for next generation energy storage applications.