Surface electrochemical processes, thermodynamics, and electrocatalysis—from extended surfaces to single atom catalysts

Abstract

Due to global energy challenges, electrocatalysis is in the focus of current research as it offers a number of solutions for efficient energy conversion and storage. However, electrocatalytic processes usually occur under very harsh conditions and one must consider possible pH and electrode potential driven changes of an electrocatalyst surface under operating conditions. Here we focus on using thermodynamic considerations to predict and understand such changes. First, we describe the thermodynamic stability of different electrocatalytic systems, focusing on the concept of Pourbaix plots, and linking these processes with electrocatalytic activity. Next, bulk materials and extended surfaces are addressed, followed with nanoparticles, ending our discussion with Single-Atom (Electro)catalysts, a relatively novel class of electrocatalysts particularly sensitive to adsorption processes at the catalytically active sites.