Nickel-Copper Oxide Catalysts Deposited on Stainless Steel Meshes by Plasma Jet Sputtering: Comparison with Granular Analogues and Synergistic Effect in VOC Oxidation

Abstract

A novel method for the preparation of Ni-Cu oxide catalysts—deposition on stainless steel meshes using hollow cathode plasma jet sputtering—was studied. This method allows the preparation of thin oxide films. Consequently, the whole volume of the active phase is readily accessible for the reactants and can be employed in the catalytic reaction due to the negligible effect of internal diffusion. As a result, the activity of our sputtered catalyst was seven times higher in ethanol oxidation and 61 times higher in toluene oxidation than that of the corresponding granular catalyst. Moreover, due to stainless steel meshes used as a catalyst support, the pressure drop across the catalyst bed was lower. Finally, the catalytic activity of the sputtered Ni-Cu oxide catalyst with Ni:Cu molar ratio of 1:1 in ethanol oxidation was 1.7 times higher than that of the commercial EnviCat® VOC-1544 catalyst, while the amount of the active phase in the catalyst bed was 139 times lower. The outstanding performance of the Ni0.5Cu0.5 catalyst was ascribed to the synergistic effect between the copper and nickel components.