Cations distribution of CuxCo3−xO4 and its electrocatalytic activities for oxygen evolution reaction

CuxCo3−xO4 spinels with different x values were synthesized by hydroxide co-precipitation method. The oxides were analyzed by TGA, XRD, BET, and SEM. The cations distribution of CuxCo3−xO4 was discussed according to the change of the copper content (x). As x value increases from 0.7 to 0.9, more Co3+ ions enter the tetrahedral sites of spinel structure. Electrochemical measurements show that the occupation of Co3+ ions in tetrahedral sites is helpful to increase the electrocatalytic activities of the spinel oxides for oxygen evolution reaction in alkaline water electrolysis.