We report on electrochemical materials and processes with strong chemomechanical effects during electrocatalysis. We are particularly focused on anode and cathode processes for electrochemical water splitting. A combination of solid state, gas phase and thin film synthetic methods are used to prepare well-defined electrode materials. An optical laser method is used to perform in-situ surface stress measurements. We also employ Raman spectroscopy and imaging to map strain fields and inhomogeneity on surfaces. Combination of these responses provide unique insight into chemomechanics of hydrogen and oxygen evolution reactions.

We will discuss the results of surface stress and strain measurements during H⁺ adsorption and early stages of hydrogen evolution on model Pt-M (M = Cu and Ni) surface alloys and bilayers. We will also report on the catalytic properties of perovskite-based transition metal oxides toward oxygen evolution reaction. We focus on perovskites and brownmillerites of the Sr_2-xCa_xFe₂O_6-δ system, where δ = 0-1. This system exhibits varying oxygen deficiency, vacancy ordering and volumetric strain. Our results suggest that vacancy content, ordering, and lattice oxygens control the oxygen evolution activity. Particularly, we will explain the role of lattice oxygens in the Sr_2-xCa_xFe₂O_6-δ system using in-situ surface stress results.