Can magnetic fields necessarily regulate electrocatalysis in catalysts with bulk ferromagnetism/ferrimagnetism?

The magnetic field represents a potent tool for modulating electrocatalytic performance, with diverse forms of physical mechanisms governing this regulation. Currently, catalysts capable of effectively enabling field regulation of oxygen evolution reaction typically exhibit bulk ferromagnetism or ferrimagnetism at room temperature. However, it is essential to note that electrocatalytic reactions are fundamentally surface chemical reaction phenomena, and discrepancies between bulk and surface magnetism may impede the achievement of magnetic field-regulated electrocatalysis, a facet seldom explored in prior research on field regulation. Importantly, our results confirm that magnetic fields do not achieve a regulatory effect in bulk ferrimagnetic Fe3O4 and CoFe2O4 catalysts at room temperature, thereby enhancing insight into the understanding of reaction mechanisms of filed-regulated electrocatalysis.