Erlangen 2018 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

MO: Fachverband Molekülphysik

MO 13: Posters 1: Ultrafast Spectroscopy

MO 13.10: Poster

Tuesday, March 6, 2018, 16:15–18:15, Orangerie

Towards understanding the mechanism of water splitting on TiO2 — Saman Hosseinpour, Simon J. Schlegel, Mischa Bonn, and •Ellen H.G. Backus — Max Planck Institute for Polymer Research, Mainz, Germany

Finding a clean and renewable energy source to replace fossil fuels has attracted much attention, the past few decades, as a requirement for the sustainable development of societies. Direct hydrogen generation on TiO2 by photocatalytic dissociation of water using sunlight was first proposed over 40 years ago. However, despite extensive work in this area, the fundamentals of the process remain ill-understood, mainly due to the lack of a proper tool to specifically explore the interface between water and TiO2. Sum frequency generation spectroscopy (SFG), is an inherently surface sensitive tool, allowing the study of the water-TiO2 interface. We show time-resolved SFG data after excitation of TiO2 with a femtosecond UV pump pulse, which mimics the sunlight. Preliminary data show that both the surface and the interfacial water molecules undergo changes on ultrafast timescales upon excitation. These UV-pump SFG-probe data illustrate the first steps towards following the photo-induced dissociation of water at the TiO2 interface in real-time.