Thermally Methanol Oxidation via the Mn@CoO(111) Facet: Non-CO Reaction Pathway.

CoO, 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 CoO(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 Mn@CoO(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 Mn@CoO(111) facet, giving rise to the stable configuration: two O* and one CHOH* adsorbates. Then, the Mn@CoO(111) facet activates the O-H and C-H bonds within CHOH*, advances CHO* → HCO* → HCOO* → COO*, and releases the products H, HO, and CO consecutively.