Unveiling the Ultrahigh-Voltage Platform of Hydrated V₃O₇ in Carbon Network for Enhancing Aqueous Zinc-Ion Batteries Performance

Aqueous zinc-ion batteries (AZIBs) have flourished as potential candidates for energy storage solutions, offering advantages like high safety, low cost, and environmental friendliness. However, their widespread application is limited by the lack of appropriate cathode materials that can operate at ultrahigh-voltage platforms and deliver enhanced performance. In this research, we investigated the potential of hydrated V 3 O 7 incorporated in a carbon network (V 3 O 7 @C) as a cathode material for AZIBs. Through a comprehensive analysis, we unveil the ultrahigh-voltage platform achieved by V 3 O 7 @C in its hydrated state, enabling superior energy storage capabilities. The hydrated V 3 O 7 @C nanosheet exhibits remarkable specific capacity, stability and Coulombic efficiency of 297.9 mAh g –1 at 0.1 A g –1 . Higher Coulombic efficiency and capacity retention of the material at 1 A g –1 are estimated to be around 95.5 and 96.5%, respectively, even after 100 cycles of charge–discharge processes in the ultrahigh-voltage platform (0–2.0 V). Furthermore, we explored the impact of H 2 O modified and C incorporated V 3 O 7 cathode material’s performance and demonstrated the significant enhancement of AZIB performance. The unique combination of ultrahigh-voltage operation, stability, and enhanced performance makes the hydrated V 3 O 7 @C an attractive candidate for advancing the development of high-performance AZIBs.