Non-thermal plasma-treated gold catalyst for CO oxidation

Abstract

The CoO_x-doped silica and its supported gold nanoparticles were synthesized by conventional thermal treatment or plasma treatment. The activity for CO oxidation displayed 100% CO conversion at only 338 K over the O₂ plasma-treated Au/CoO_x/SiO₂-PO catalyst. Analysis of the results suggested that, different from the traditional calcined gold catalyst, the metal particles in the plasma-treated samples tended to be smaller and more homogeneous and highly dispersed on the surface of the support. The microstructure with a large surface contact and mesoporosity was more appropriate for the reactions. In addition, the O₂ atmosphere plasma-treated samples generated a large amount of oxygen-supply centers, which in turn facilitated the low-temperature CO oxidation reaction. The plasma technique under an oxygen atmosphere is proved as an efficient treatment technique for gold catalysts.