The Energy of Hydroxyl Coadsorbed with Water on Pt(111)

Abstract

Adsorbed OH is a key intermediate in many catalytic reactions and a common species on many materials' surfaces. We report here measurements of the calorimetric heats for forming the widely studied and structurally well-defined coadsorbed (H2O···OH) complex on Pt(111) from water vapor and adsorbed oxygen adatoms. We further use these heats as benchmarks to evaluate the performance of density functional theory, modified to include van der Waals interactions and zero-point energies, and find agreement to within 1 and 15 kJ/mol for the two adlayer structures studied.