Enhanced electrocatalytic performance of N-doped Yolk-shell Co3O4 for methanol oxidation in basic solution

Developing clean and renewable energy to replace fossil fuels becomes an urgent task. Especially, direct methanol fuel cells (DMFC) are considered as the potential candidate. The large-scale application of Pt-based electrocatalysts as the most active electrocatalysts towards methanol oxidation is limited by the cost and scarcity. Therefore, exploring low-cost electrocatalysts with higher catalytic activity has been focused on by scientists from different countries. In this work, we have prepared the N doped Co3O4 hollow microspheres as highly efficient electrocatalysts towards methanol oxidation in basic solution. The electrocatalytic activity of N-Co3O4 toward methanol oxidation in the mixture of KOH (1 M) and CH3OH (1 M) is evaluated by cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscopy. In comparison with that of the existing non-metallic doped metal oxide modified electrodes, the prepared N-Co3O4 demonstrates higher electrocatalytic activity together with higher stability toward methanol oxidation. The current density of N-Co3O4 is 23.87 mA cm−2 toward methanol oxidation, which is 3.2 times higher than that of Co3O4 (7.47 mA cm−2). The current retention rate of N-Co3O4 and Co3O4 is 65.7% and 58.3% after 500 cycles, respectively.