The importance of surface coverages in the rational design of electrocatalysts

In the last few decades, the research community has witnessed a renewed and increasing interest in electrocatalysis as a powerful tool to sustainably produce chemicals and fuels using renewable electricity. While computational studies can accelerate the discovery of more efficient and cheaper electrocatalysts, they may decelerate the process if unphysical models are used to describe chemical reactivity on the electrode surface. In this opinion piece, we highlight the importance of assessing the resting state of electrocatalysts under reaction conditions, and outline how this can be achieved through the construction of energy diagrams which portray the relative stability of surface coverages that are likely to form in aqueous electrolytes at different applied potentials and pH values. Lastly, we discuss the limitations of the current models and the prospects for further developments in the field.