1 Department of Physics, Technical University of Denmark2 Center for Atomic-scale Materials Design, Center, Technical University of Denmark3 Department of Energy Conversion and Storage, Technical University of Denmark4 Atomic scale modelling and materials, Department of Energy Conversion and Storage, Technical University of Denmark5 Experimental Surface and Nanomaterials Physics, Department of Physics, Technical University of Denmark6 Ruhr-Universität Bochum
The unexpectedly high measured activity of Pt[n(111) × (111)] and Pt[n(111) × (100)] stepped single crystal surfaces towards the oxygen reduction reaction (ORR) is explained utilizing the hydroxyl binding energy as the activity descriptor. Using this descriptor (estimated using experimental data obtained by different groups), a well-defined Sabatier-type volcano is observed for the activities measured for the Pt[n(111) × (111)] and Pt[n(111) × (100)] stepped single crystals, in remarkable agreement with earlier theoretical studies. We propose that the observed destabilisation of *OH species at these surfaces is due to the decreased solvation of the adsorbed hydroxyl intermediates on adjacent terrace sites.
Physical Chemistry Chemical Physics, 2014, Vol 16, Issue 27, p. 13625-13625