Medium-energy mechanosynthesis parameters enhancing the dry reforming of methane over Ni/CeO2 catalysts

Ni/CeO 2 catalysts for dry reforming of methane (DRM) were prepared via a medium energy, solvent-free mechanochemical route by ball milling ceria with Ni precursors (nitrate or chloride salts). The effect of precursor type and milling time on surface area, structure, and redox properties was assessed by N 2 -physisorption technique (BET), X-ray powder diffraction (XRD), and H 2 -temperature programmed reduction (H 2 -TPR). Catalytic performance was benchmarked against catalysts prepared by incipient wetness impregnation (IW). Brief milling produced catalysts with higher initial activity and, in selected cases, a more favorable activity-retention behavior than the impregnated reference. Results from a multi-technique analytical approach which combines high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure (NEXAFS), indicate that the mechanical action promotes the formation of a distinctive Ni–ceria interfacial nanostructure, whose distribution and accessibility depend on mechanochemical synthesis parameters and correlate with catalytic behavior in DRM.