Catalytic decomposition of nitrous oxide on grafted CuO/γ-Al2O3 catalysts

Abstract

Copper oxide supported on alumina has been prepared by grafting from the liquid phase. This method allows for the controlled deposition of individual CuO-sites at sub-monolayer coverage. By repeated grafting reactions, complete layers can be formed, and thicker layers built up. The properties of these catalysts change with the amount of deposited metal oxide. Isolated metal ions show little catalytic activity towards the decomposition of N2O. Only after the third grafting do pair sites form at the surface, and the catalytic activity normalized per metal ion in the surface increases about 4-fold. In contrast, the specific activity of catalysts prepared by conventional wet impregnation and by mechanical mixing is independent of loading. Monolayer catalysts synthesized by multiple grafting are more active with respect to the decomposition of nitrous oxide (N2O) than are catalysts prepared by impregnation or mechanical mixing.