Manganese oxide with hollow rambutan-like morphology as highly efficient electrocatalyst for oxygen evolution reaction

The research about oxygen evolution reaction (OER) has attracted extensive attention. In this work, different manganese oxides with different shell thickness were firstly grown on the surface of carbon ball template, and then the carbon ball was removed by high-temperature calcination in air to obtain hollow rambutan-like Mn2O3 and MnO2-Mn2O3 with long nanowires. The concentration of inorganic manganese salt and the reaction time has a determining influence on the morphologies of manganese oxide. The as-prepared MnO2-Mn2O3 exhibits a lower overpotential than the Mn2O3 to achieve a current density of 10mAcm(-2). The Faradic efficiency of MnO2-Mn2O3 reaches to 94.1% during the bulk electrolysis, and the morphology of MnO2-Mn2O3 remains virtually unchanged after electrolysis, indicating the outstanding stability of the as-obtained MnO2-Mn2O3.