Thermally Methanol Oxidation via the Mn₁@Co₃O₄(111) Facet: Non-CO Reaction Pathway

Co₃O₄, as the support of single-atom catalysts, is effective in electron-structure modulation to get distinct methanol adsorption behaviors and adjustable reaction pathways for the methanol oxidation reaction. Herein, we considered the facets that constitute a Co vacancy of the Co₃O₄(111) facet and a foreign metal atom M (M = Fe, Ni, Cu, Ru, Rh, Pd, Ag, Os, Ir, Pt, Au, Mn) leading to single-atom catalysts. The Mn₁@Co₃O₄(111) facet is the facet considered the most favorable among all of the possible terminations. Oxygen adsorption, decomposition, and its co-adsorption with methanol are the vital steps of methanol oxidation at the exposed Mn₁@Co₃O₄(111) facet, giving rise to the stable configuration: two O* and one CH₃OH* adsorbates. Then, the Mn₁@Co₃O₄(111) facet activates the O-H and C-H bonds within CH₃OH*, advances CH₃O* → H₂CO* → HCOO* → COO*, and releases the products H₂, H₂O, and CO₂ consecutively.