Dual Activation of Molecular Oxygen and Surface Lattice Oxygen in Single Atom Cu /TiO Catalyst for CO Oxidation.

The in-depth mechanism on the simultaneous activation of O and surface lattice O on one active metallic site has not been elucidated yet. Herein, we report a strategy for the construction of abundant oxygen activation sites by rational design of Cu /TiO single atom catalysts (SACs). The charge transfer between isolated Cu and TiO support generates abundant Cu and 2-coordinated O sites in Cu -O-Ti hybridization structure, which facilitates the chemisorption and activation of O molecules. Simultaneously, the Cu -O-Ti induced TiO lattice distortion activate the adjacent surface lattice O , achieving the dual activation of O and surface lattice O . The Cu -O-Ti active site switches the CO oxidation mechanism from Eley-Rideal (80 °C) to Mars-van Krevelen route (200 °C) with the increase of reaction temperature. The dual activation of O and surface lattice O can by modulating the electron properties of SACs can boost the heterogeneous catalytic oxidation activity.