On the tunability of chemical reactions at metal-oxide interfaces

The model system Cr/SrTiO3 was used to show how interfacial reactions can be tuned over a temperature range of several hundred Kelvin by a distinct modification of the electronic structure in the oxide. This mechanism unveils the dominant role of the Fermi energy level (EF) in the oxide's band gap for interfacial reactions and can be understood by the interplay between the outward diffusion of oxygen ions and space charges formed at the Cr/SrTiO3 interfaces. The results suggest that the interfacial reactivity is tunable by modifying EF in the oxide, which will be decisive for present and future applications in the fields of sensors, catalysis and microelectronics.