Electrochemical capacitance of mesoporous tungsten oxynitride in aqueous electrolytes

▸ Tungsten oxynitride W0.75(N,O) is evaluated as an electrode material for supercapacitors. ▸ The electrochemical properties of W0.75(N,O) are studied in aqueous electrolytes. ▸ Maximum capacitance is observed in H2SO4 electrolyte and maximum stability is found in KOH electrolyte. ▸ The contribution of a pseudocapacitive charge storage mechanism is proposed.