Au−Cu Alloy Nanocluster Doped SiO2 Films by Sol−Gel Processing

Au−Cu alloy nanocluster formation in silica films has been achieved in the present study by sol−gel processing. A fundamental role for obtaining alloy clusters instead of separation of the metallic species is played by the annealing atmosphere. Annealing in reducing atmosphere (hydrogen-containing) results in Au−Cu alloy formation, whereas air annealing promotes not only Au cluster precipitation and Cu oxidation but also Au−Cu alloy separation in samples previously annealed under reducing atmosphere.