Impact of Water Coadsorption on the Electrode Potential of H-Pt(1 1 1)-Liquid Water Interfaces
Phys. Rev. Lett.: RESOLV member Prof. Jörg Neugebauer's study derives a chemically intuitive model for metal-water bonding that explains an unexpectedly large interaction between coadsorbed water and adsorbates and explain the origin behind the experimentally observed upper limit of H coverage well below one monolayer.
This research investigates how water influences adsorption and electrode potential at H-covered Pt(111) interfaces, focusing on the 0.66 ML upper limit of hydrogen adsorption in aqueous environments, which does not occur in dry conditions. Key findings reveal that water actively shapes surface chemistry by influencing adsorption, electrode potential, and the onset of the hydrogen evolution reaction (HER). The study also explores how coadsorbed water molecules interact with adsorbates, with chemisorbed water driving potential shifts and limiting hydrogen adsorption at higher coverages.
