Thermal behaviour of Cu and Au nanoparticles grown on CeO2 thin films

Bimetallic catalysts are often more active and/or selective than their monometallic counterparts. The behaviour of such is frequently strongly dependent on the molar ratio two elements as well nanoparticle size and interaction with support material. X-ray photoelectron spectroscopy (XPS) an excellent surface analytical technique for probing electronic properties catalytic systems. When a mixture pure alloyed particles present, it difficult to extract information from XPS given that spatial averaging technique. Recently, medium energy ion scattering (MEIS) has been exploited investigate depth-dependent composition nanoparticles planar surfaces. Herein, we combine techniques nature Cu Au deposited onto ultrathin CeO2 films Si(1 1 1) examining morphology chemical function annealing temperature samples have maintained in ultrahigh vacuum environment exposed air. Cu/Au/CeO2/Si(1 chosen model system order provide insight into how Cu/Au/CeO2 depend presence discrete versus fully intermixed Cu/Au