PEDOT-coated VOOH nanoparticles as a high-capacity cathode for aqueous zinc-ion battery

[Display omitted] •VOOH nanoparticles are prepared through a one-step hydrothermal method.•PEDOT coating improves the conductive and structural stability of VOOH.•VOOH@PEDPT shows high discharge capacity and good rate performance.•Ex-situ XRD tests reveal Zn2+/H+ co-insertion mechanism. The vanadium oxyhydroxide has attracted considerable attention as a cathode in aqueous zinc-ion batteries due to its changeable morphology and high theoretical capacity. However, poor conductivity and structural disintegration limit its further application. Herein, we prepare VOOH nanoparticles and apply them onto carbon cloth, followed by coating with poly(3,4-ethylenedioxythiophene) (VOOH@PEDOT). The PEDOT coating layer and carbon cloth substrate significantly mitigate volume change and enhance electrode conductivity during cycling. Benefiting from the improved charge transfer and structural stability, the optimized VOOH@PEDOT displays an excellent discharge capacity of 230 mA h/g and good cycle stability over 500 cycles at 1 A/g. Additionally, the energy storage mechanism is elucidated through ex-situ XRD analysis.