The Doping of Al at the Tetrahedral Site of Spinel MnO for Electrocatalytic Water Oxidation.

Spinel oxides have attracted much attention for electrocatalytic water oxidation. Specially, the Mn-based spinel structures merits fundamental investigation, as Mn is involved in water oxidation in natural photosynthesis. Herein, Al-doped MnO spinel electrocatalyst was prepared for water oxidation. The Al cations selectively occupy the tetrahedral sites of MnO spinel structure, leaving Mn(III) at the catalytically critical octahedral sites. The substitution of Al regulated the electronic structure of MnO, induced lattice distortion and produced higher concentration of oxygen vacancy to promote the water oxidation performance.