Vanadium-doped magnesium oxide nanoparticles as electrodes in supercapacitor devices

Official URL: https://dx.doi.org/10.1016/j.jallcom.2023.170442

Vanadium (V)-doped MgO nanoparticles were used as electrode materials in all-in-one solid-state supercapacitor applications. The prepared samples’ structural and morphological properties were thoroughly analyzed using XRD, Raman spectroscopy, TEM, PL, and BET. EPR spectroscopy was employed to analyze the paramagnetic centers induced in the host material and showed that all V-doped samples displayed a V4+ characteristic EPR signal. The electrochemical analysis of the assembled symmetric supercapacitors was done using cyclic voltammetry, galvanostatic cycling with potential limitation technique, and potentiostatic electrochemical impedance spectroscopy. The results reveal that the novel V-doped MgO material displayed excellent capacitance performance between 0 and 1 V, delivering a specific capacitance of 50 F/g at a 10 mV/s scan rate. It also exhibits a maximum energy density of 4.17 Wh/kg, comparable to values obtained from other symmetric supercapacitor configurations. When a booster material like carbon black was added, the specific capacitance value increased dramatically to 1200 F/g, values that were never reported before in the literature for MgO-based materials.