Designed Synthesis of Co2VO4 Nanodiscs with Large Aspect Ratios To Achieve a High-Capacity Enhancement of 20.2% for Photorechargeable Zinc Ion Batteries

The overall performance of the photorechargeable batteries (PRBs) have been restricted by poor light adsorption, sluggish kinetics of photoelectrons and holes, and inevitable photocorrosion of the electrodes. Herein, cobalt vanadate (Co₂VO₄) nanodiscs with a large aspect ratio (∼8.9) were prepared, which showed a maximum surface photovoltage of 188 mV with good light absorption, leading to enhanced photocurrent and reduced resistance upon light irradiation. The assembled zinc ion batteries (ZIBs) delivered a specific capacity of 107.06 mAh g^-1 at 1 A g^-1 under light, corresponding to a light enhancement of 20.2%. A capacity retention of 67.7% was obtained after 300 cycles, demonstrating an alleviated photocorrosion.