Tuning lamellar structure of vanadium oxide via inorganic–organic hybridization engineering for high-performance aqueous zinc-ion storage

Vanadium oxides, stand out as promising cathode candidates for aqueous zinc ion batteries due to their adjustable layer structure and high theoretical capacity. However, challenges such as low electronic conductivity, large Zn²⁺ ionic potential and sluggish Zn²⁺ diffusion kinetics in aqueous electrolytes during long charging/discharging cycles still hinder their potential application. Herein, we present an inorganic-organic hybridization engineering by utilizing poly (3,4-ethylenedioxythiophene) (abbreviated as PEDOT) as a rigid support insert into the layers of vanadium oxide (LVO) to improve the zinc ion storage properties of vanadium matrix composites. The LVO@PEDOT cathode exhibits superior rate capability of 308.7 mAh g⁻¹ at 1 A g⁻¹ and 155.4 mAh g⁻¹ at 10 A g⁻¹. Furthermore, the LVO@PEDOT maintains a long-term stability of about 81.9 % of the initial capacity after 5000 cycles. Moreover, the density functional theory (DFT) results reveal that the adsorption energy can be drastically reduced after composite organic conducting polymers PEDOT. Based on these findings, we convince that this inorganic-organic hybridization strategy shows significant potential as a cathode material for aqueous zinc-ion batteries (AZIBs). This work sheds novel light on the development of high-performance vanadium-based energy storage materials, which would accelerate the exploration of other metal oxide-based materials.