Operando X-ray Raman Scattering for Probing Lattice Oxygen Mediated Pathways in Electrocatalysts for the Oxygen Evolution Reaction

The adoption of electrolyser technology for hydrogen production by water splitting is hampered by the high overpotential of the oxygen evolution reaction (OER). The recently identified Lattice Oxygen Mediated (LOM) mechanism for OER offers a promising route to significantly improve the efficiency of water splitting. O K-edge and transition metal (TM) L-edges provide a direct probe of TM-O hybridization that could reveal the underlying mechanism of LOM OER. However, the short attenuation length of soft X-rays, precludes realistic operando studies with soft X-ray absorption spectroscopy. This proposal aims to use X-ray Raman Scattering (XRS) as a hard X-ray probe of shallow core levels to enable operando measurements of the TM and O redox processes occurring under OER conditions. This will provide new understanding of the LOM mechanism of O2 evolution under high overpotential conditions to inform the rational design of improved electrocatalysts