Mn-oxides catalyzed periodic current oscillation on the anode

•Electrochemical oscillation was first observed in oxidation of Mn(II) solution.•The oscillation accounts for extra power consumption (>14%).•The oscillation originates from the Mn-oxide-catalyzed electro-oxidation of water.•The oscillation well agrees with the calculation based on a dynamic mechanism.

Periodic current oscillation on the anode is reported for the first time in the electro-oxidation of aqueous Mn2+ solution. It originates from the Mn-oxide-catalyzed electro-oxidation of H2O, and shows significant dependence on both the anode potential and the micro-structure of Mn oxides. The oscillation accounts for extra power consumption (>14%). The experimental current–time curve well agrees with the preliminary theoretical calculation results, which lead to a hypothetical dynamic mechanism for the oscillation. This work provides insight into the microscopic electrochemical mechanism underlying the macroscopic non-equilibrium phenomenon, and new evidences for the mechanism of Mn-oxide catalyst.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide