Mn-doped Co3O4 nanoarrays as a promising electrocatalyst for oxygen evolution reaction

Microstructures and electrocatalytic characteristics of a series of MnxCo3-xO4 nanostructures for oxygen evolution reaction were investigated by adjusting hydrothermal reaction time, temperature and the molar ratio of Mn2+/Co2+, followed by an alkali treatment at room temperature. The results indicate that the synthesis process is optimal when hydrothermal reaction time, temperature and the molar ratio of Mn2+/Co2+ are 10 h, 100 degrees Cand 1:3, respectively. Under this condition, Mn(x)Co(3-)xO(4) possesses an optimal electrocatalytic performance for OER. Moreover, after treated in the mixed alkali solution of 1 M NaBH4 and 3 M NaOH, the catalytic performance of MnxCo3-xO4 for OER has been enhanced furtherly. The unique architecture and its corresponding morphology after alkalization treatment, such as highly exposed active sites and high surface roughness, are mainly responsible for its excellent electrocatalytic performance for the OER process.