Electrochemically fabrication of a composite electrode based on tungsten oxide and cobalt on 3d ni foam for high and stable electrochemical energy storage

Abstract

The present work reports new findings on the electrical energy storage capabilities of WO3/Ni and Co@WO3/Ni electrodes produced via galvanostatic electrochemical deposition. The paper also describes a novel process for cleaning Ni foam, which has significant effect on the electrode's charge accumulation properties. Electro-chemical measurements in an aqueous solution are performed to compare the supercapacitive behavior of the WO3/Ni foam and Co@WO3/Ni foam. The specific capacitance of the former electrode increases from 492.8 to 977.4 F g-1 because of Co adding into tungsten oxide. Furthermore, the former has 42.5% capacitance retention after 7000 charge-discharge cycles, while the latter has 83.7% owing to the Co loading. The specific energies are respectively calculated to be 64.27 Wh kg-1 and 64.44 Wh kg- 1 for the pure WO3/Ni and Co@WO3/Ni elec-trodes. The specific powers are 3761.49 W kg- 1 and 3303.90 W kg- 1 for the former and latter electrodes. Ac-cording to the findings, adding Co to the pure WO3/Ni electrode increases its electrochemical and supercapacitor capabilities, allowing it to be used in energy storage devices.