COSAS · Controlling Oxygen Selectivity at the Atomic Scale

Developing new materials with optimized catalytic properties is a crucial challenge towards sustainable energy production. In order to achieve this long-standing goal, fundamental understanding of the processes taking place at the electrode-electrolyte interface is vital. Progress here requires a comprehensive atomic-scale picture of the fundamental chemical and catalytic properties of surfaces, in connection to their macroscopic catalytic performance. This knowledge remains hindered due to the complexity of real catalytic systems and the lack of experimental techniques that can provide information of the catalytic process from single-molecule interaction to operando conditions.The project COSAS focuses on the electrochemical water oxidation to hydrogen peroxide and seawater electrolysis. It proposes an atomistic study of the electrode-electrolyte surface to unveil the key parameters for selective activation of alternative reaction paths for water oxidation. The experimental approach of the project represents a novel quasi-in situ electrochemical characterization (near ambient pressure x-ray photoemission spectroscopy), combined with atomic-scale access to the electronic structure (scanning tunnelling microscopy and spectroscopy) on the very same sample. The project will study thin films of transition metal oxides as model systems for exploring structure-function relationships, while presenting catalytic relevance for oxygen related reactions. The unique methodology of the project promises novel atomistic insight in the mechanism behind complex reactions with multiple intermediates, unveiling key parameters that can guide the design of active and selective electrocatalysts for cost-effective water electrolysis.