Waste material derived catalyst of positive half-cell electrode for vanadium redox flow batteries

Due to the steadily increase in the energy from renewable sources, the large-scale storage devices become very important to tackle its intermittent nature. Vanadium redox flow batteries (VRFBs) are viable option for this purpose. Two following biomass waste materials are investigated to prepare the catalyst for the positive half-cell carbon woven electrode, 1) the waste leaves of the trees 2) Goat manure. The cyclic voltammetry and linear sweep voltammetry is used for initial micro electrochemical analysis. The anodic peak current is increased from 11.1 mA to the 23.71 mA, while cathodic peak current is increased from −6.7 mA to −18.9 mA in cyclic voltammetry analysis. The positive half-cell charge discharge cycles show the average increase of 38 mA in anodic current, while −17 mA increase in cathodic current in 90 min charge discharge electrolysis. The constant potential density functional theory calculations at 1.2 V shows that the oxygen doped surfaces have better affinity with anolyte, as it shows −7.01 eV adsorption energy in comparison of −3.49 eV of untreated electrode.