Water does more than surround a photocatalyst—it actively shapes the reactions at its surface. In our new study, accepted for publication in Angewandte Chemie International Edition, we investigate how water and surface hydroxyl groups promote methanol decomposition on titanium dioxide (TiO₂).
The work brings together researchers from TU Dortmund University, Henan University, Université Paris-Saclay, Ruhr University Bochum, and Beihang University. Combining surface-sensitive sum-frequency-generation spectroscopy with theoretical calculations, we show how hydrogen-bonding networks facilitate proton transfer and lower the energy barrier for methanol dissociation. Under ultraviolet illumination, the hydrated interface also promotes further oxidation by stabilizing localized charge carriers and supporting cooperative proton transfer.
These findings connect insights from idealized vacuum experiments with chemistry at realistic solid–liquid interfaces, helping guide the development of photocatalytic systems for energy conversion and sustainable chemical production.

Read the paper in Angewandte Chemie International Edition