Spin‐Dependent Reconstruction Induced by Surface Symmetry Breaking in Manganese Spinel Oxides Toward Acidic Oxygen Evolution Reaction

The spin‐related electronic occupation at the catalyst surface plays an important role in determining the acidic oxygen evolution reaction (OER), which can directly affect the bonding interaction and electron transfer with reactants. Herein, a series of manganese spinel oxides with good acidic stability are suggested to regulate the catalytic activity by surface engineering, in which the orbital splitting and electronic reconfiguration are strongly dependent on the surface symmetry breaking. The detailed analysis of electronic structure demonstrates that the magnetic moments of half‐filled 3 d metals at surface layers are obviously larger than that at the internal region. This difference in spin electron occupation makes it display a higher catalytic activity in acidic OER. This work suggests a new strategy to enhance catalytic activity by spin‐related surface engineering.