Bimetallic Au–Pt Nanocomposites in the CO Oxidation Reaction: New Synthetic Approach and Evolution in the Course of Catalysis

Resumo

A combination of two green chemistry methods—fluid (supercritical carbon dioxide) and metal vapor synthesis—has afforded γ-Al₂O₃-based systems modified with Au, Pt, Au–Pt, and Pt–Au nanoparticles. It has been shown that bimetallic nanocomposites in the CO oxidation reaction are more efficient catalysts than monometallic systems. The composition of the Au–Pt/Al₂O₃ intermetallic compound and its evolution in the course of catalysis have been studied by X-ray photoelectron spectroscopy. It has been demonstrated that the increase in system activity during catalysis is accompanied by a significant rearrangement of the structure and composition of the nanocomposite surface.