Operando HERFD XANES study of bimetallic Co-Mo-based catalysts for ammonia decomposition

Ammonia is gaining importance as a potentially renewable and carbon-free energy carrier. One of the ways to extract energy from ammonia includes its decomposition to hydrogen which requires efficient and afford-able catalysts. Bimetallic Co-Mo-based catalysts are considered a possible promising alternative to more active but also more expensive ones based noble metals. This study investigates catalysts of ammonia decomposition for hydrogen production that contain oxides, nitrides, and carbides of Co and Mo to establish structure-activity relationships in these systems. Identifying and distinguishing these O-, N-, and C-containing phases of the same metal is challenging and requires analysis by HERDF XANES, valence-to-core XES, and RIXS to maximise sensitivity to changes in the ligand environment.