Synergistic H+/Zn2+ co-insertion mechanism in vanadium trioxide composited on carbon nanotubes cathode for aqueous zinc ion batteries

Due to their nontoxicity, low cost, and high capacity, aqueous zinc-ion batteries (AZIBs) have been the subject of substantial research and are considered a viable replacement for lithium-ion batteries (LIBs). However, AZIB cathodes suffer from dissolution and structural collapse during charging and discharging, which severely limits their use. By the in-situ compounding of V2O3 and carbon nanotubes, we developed a unique composite cathode material (V2O3/CNT) to provide oxygen vacancies in the cathode in AZIB, and have achieved a remarkable electrochemical performance (211.6 mAh g−1 after 2000 cycles at 5 A g−1). The V2O3/CNT can maintain a capacity of 137.3 mAh g-1 with a large current density of 10 A g-1 after 4000 cycles. A combination of ex-situ XRD and other characterization techniques revealed that the superior zinc storage of V2O3/CNT is primarily due to its ultra-stable structure, oxygen-rich defects, and H+/Zn2+ co-intercalation mechanism. The in-situ manufacture of oxygen-defective-rich vanadium oxide on carbon nanotubes may be an efficient approach to creating high-performance AZIBs cathode materials.