The interaction of CO2 and CO with Fe-doped SrTiO3(100) surfaces

The interaction of CO2 and CO with 0.013 at.% Fe-doped SrTiO3(100) was investigated in situ with Metastable Induced Electron Spectroscopy (MIES) and XPS at room temperature. To clear up the influence of surface defects, cleaned and sputtered SrTiO3 surfaces were investigated. Sputtering results in the breaking of TiO bonds in the surface and the formation of oxygen-related defects as well as reduced titanium on the surface. Cleaned SrTiO3 surfaces do neither interact with CO2 nor with CO. Sputtered surfaces show a CO formation during CO2 exposure and—to a lesser extent—during CO exposure. The CO groups can be detected very well with MIES because of its extreme surface sensitivity. With XPS, the characteristic carbonate peak shift of the C 1s orbitals can be detected. Copyright © 2011 John Wiley & Sons, Ltd.