Generation of oxide surface patches promoting H-spillover in Ru/(TiO x )MnO catalysts enables CO 2 reduction to CO

The migration of reducible metal oxides (for example, TiO 2 ) to the surface of metal nanoparticles can inhibit sintering but has a strong negative impact on the catalytic activity. Here we reveal the in situ creation of TiO x patches over an MnO support to generate effective transport channels for hydrogen spillover to form more active hydrogen species on the MnO surface which are responsible for reducing CO 2 to CO, a key reaction for CO 2 conversion to high-value chemicals. The Ru/(TiO x )MnO (Ru/Ti/Mn) catalyst shows a 3.3-fold increase in reverse water-gas shift performance compared with conventional Ru/MnO x catalysts. Through a combination of physicochemical methods, including in situ studies, catalytic and kinetic data, and theoretical modelling, we demonstrate that the oxide–oxide interfaces are spontaneously generated during reductive treatment in H 2 , contributing to the increased activity. The results open perspectives for the design of novel selective hydrogenation catalysts via the in situ creation of oxide–oxide interfaces acting as hydrogen-species transport channels.