Perspectives of in situ/operando resonant inelastic X-ray scattering in catalytic energy materials science

Growing environmental concerns have renewed the interest for light induced catalytic reactions to synthesize cleaner chemical fuels from syngas. This, however, requires a sound understanding for the dynamics taking place at molecular level as a result of light - matter interaction. We present herein the principles of soft X-ray resonant emission spectroscopy (RXES) and resonant inelastic scattering (RIXS) and the importance of these spectroscopic techniques in materials science in light of their unique ability to emanate characteristic fingerprints on the geometric structure, chemical bonding charge and spin states in addition to chemical sensitivity. The addition of in situ/operando RXES and RIXS capability offers new opportunities to project important material properties and functionalities under conditions nearly identical to the operational modes.