VO2-C Materials Prepared from Citric Acid Organic Skeleton as C Matrix as Anode for Aqueous Zinc Ion Batteries

Designing and synthesizing cathode materials with high specific capacity and stability for aqueous zinc ion battery remains a significant challenge. In this study, citric acid was selected as the reducing agent for converting V 2 O 5 to VO 2 with a carbon matrix using the hydrothermal method. The introduction of citric acid not only created a distinct microstructure in V 4+ materials but also provided carbon matrix, which resulted in a fast diffusion of zinc ion and a good conductivity. This carbon containing vanadium-oxide material exhibited excellent electrochemical performance as a cathode material for aqueous zinc ion batteries, showing a high specific capacity of 399.33 mAh g −1 at 1 A g −1 , and a capacity retention rate up to 98.3% after cycling for 1000 cycles at a high current density of 5 A g −1 .