Methanol Dehydrogenation via Rutile TiO₂-Based Single-Atom Catalysts: Structure, Stability, and Selectivity

Abstract—Single-atom catalysts possessing distinct geometric and electronic structures have permitted the highly efficient performance and tunable catalytic property for methanol dehydrogenation. The structure and stability of rutile TiO₂-based single-atom catalyst, and the selectivity for methanol dehydrogenation were addressed via DFT + U calculations. The stable single-atom catalysts: rutile Co₁@TiO₂ and Ru₁/TiO₂, have been identified from all the possible terminations. Their interface structures, stabilities in thermodynamics, and selectivity for methanol dehydrogenation are determined by the two important parameters: metal-atom doping site and surficial oxygen stoichiometry. In particular, the substitutional rutile Co₁@TiO₂(110) facet can boost direct methanol dehydrogenation, activate O–H and C–H bonds, and then release formaldehyde, H₂, and CO. The rutile Ru₁/TiO$_{{2 + x}}$(110) one, a supported neutral Ru atom with additional oxygen on the stoichiometric rutile TiO₂(110) facet, prefers to facilitate partial oxidation of methanol.