文摘
Alumina-supported platinum鈥搒ilver alloy nanoparticle (Pt鈥揂g/Al2O3) catalysts with different particle composition have been prepared using a wet chemistry method and studied for the property in carbon monoxide oxidation reaction. The Pt鈥揂g alloy catalyst exhibits significantly improved activity and largely decreased activation energy barrier compared to those of both pure Pt and pure Ag catalysts in the room temperature range. The Langmuir鈥揌inshelwood mechanism, in which surface Pt active sites chemisorb CO and adjacent Ag sites activate O2, was proposed and discussed to explain the promoted CO oxidation kinetics on the Pt鈥揂g alloy. Thermal stability of the Pt鈥揂g alloy catalyst under the reaction condition was also investigated using in situ Fourier transform infrared spectroscopy experiments and transmission electron microscopy characterizations.