WO₃/CoWO₄/rGO high porosity anode electrode materials based on ZIF-67 framework

Promising as an anode material, WO₃ shows good reversibility and a high specific capacity. However, its drawbacks, including volumetric expansion and low electrical conductivity, hinder its further development. In this work WO₃/CoWO₄/rGO particles were prepared using a ZIF-67-derived porous carbon polyhedrons via hydrothermal methods. ZIF-67 frame with high porosity increases the specific surface area available for ion insertion and extraction, enhances electrolyte infiltration, speeds up ion diffusion, and prevents WO₃/CoWO₄ volume expansion during the cycle. The low conductivity of composite materials was compensated for by the high conductivity of rGO. The material exhibits a notable initial reversible capacity of 507.8 mAh g⁻¹ after undergoing 100 cycles at the current density of 100 mA g⁻¹ and 248.3 mAh g⁻¹ specific capacity was retained after 300 cycles at the current density of 800 mA g⁻¹.