Interaction of 2-propanol with predominantly SrO- and TiO2-terminated SrTiO3(100) surfaces studied by vibrational sum frequency spectroscopy

Abstract

The interaction of 2-propanol with SrTiO₃(100) surfaces is studied with a focus on the role of different surface terminations in the deprotonation upon adsorption. Preferential SrO and TiO₂-termination was corroborated by AFM, ARXPS and SIMS. Surface sensitive vibrational sum frequency spectroscopy (vSFS) reveals that 2-propanol predominantly adsorbs intact on SrO-terminated SrTiO₃(100), but is to a large extent deprotonated on TiO₂-terminated SrTiO₃(100). The latter is in contrast with the lack of deprotonation of 2-propanol when interacting with thin film TiO₂ as reported earlier.