Vanadium-Doped Magnesium Oxide Nanoparticles As Electrodes In Supercapacitor Devices

Official URL: https://risc01.sabanciuniv.edu/record=b3205726

Magnesium Oxide (MgO) occupies a special stature as a material for energy-storage purposes, owing to its abundance, sustainability, and phenomenal electrochemical features. Vanadium (V) is another unique material, where vanadyl ions (V4+) can be utilized as probing agents to reveal information in characterization spectroscopies that require paramagnetic centers, and to introduce extrinsic defects into host materials to enhance the electrochemical properties. Here in, we report V-doped MgO nanoparticles as electrode materials in all-in-one solid-state supercapacitor devices. The prepared samples’ structural, morphological, electronic, and optical properties were thoroughly analyzed utilizing XRD, Raman spectroscopy, STEM, EPR, and PL. 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 (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic cycling with the potential limitation technique (GCPL). 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 at 20 mV/s, values that were never reported before in the literature for MgO-based materials.