Expanding the frontiers of hydrogen evolution electrocatalysis–searching for the origins of electrocatalytic activity in the anomalies of the conventional model

After decades of research, understanding the origins of electrocatalytic activity remains a fundamental scientific challenge. While most of the efforts were directed towards comprehending what dictates bonding of intermediates, attempts to go beyond the paradigm of optimal adsorption energies are rare. In this work, by analysis of the conventional hydrogen electrocatalysis model, and by comparative analysis of Pt and Pd, we propose what can be an important contributor to electrocatalytic activity, besides adsorption energies of intermediates. Discussion is initiated about the possible link between bulk electronic structure of a metal and charge transfer coefficient (including symmetry factor of activation barrier) as a key contributor to electrode reaction rate.