Deposition of an oxide on sub-monolayer amounts over a second oxide host can create nanostructures which in turn may enhance the overall catalytic properties of the entire system. Depositing ceria on TiO2(110) leads to the formation of ceria dimmers. We uncovered an unexpected electronic influence, coined as 'electronic metal–support interaction' (EMSI), of these ceria dimers on the reactivity of small co-deposited platinum particles for reactions involving water cleavage [1]. The importance of metal–oxide interfaces has long been recognized, but the molecular determination of their properties and role is only now emerging. Atoms with properties ranging from metallic to ionic are available at the metal–oxide interface and create unique reaction sites. We have shown that the activation of an efficient associative mechanistic pathway for the water–gas shift reaction by an oxide–metal interface leads to an increase in the catalytic activity of ceria nanoparticles deposited on Cu(111) or Au(111) by more than an order of magnitude. In situ experiments demonstrated that a carboxy species formed at the interface is the critical intermediate in the reaction [2,3]. Our studies point to a new paradigm in the design of catalysts: The optimization of the oxide phase and the metal-oxide interface in a catalyst can improve substantially its activity and selectivity.

Power of oxide-metal interfaces: In-situ studies of the water-gas-shift reaction

253rd National Meeting (2017)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.