Detoxification of NO and CO gases over effectively substituted Pd and Rh in cupric oxide catalysts

Abstract

Precious metals like Pd and Rh mixed with metal oxides exhibit a superior CO adsorption capacity, and thus their substitution has considerable effect on surface property of cupric oxide. This communication focuses on Pd and Rh substitution in cupric oxide and their catalytic application in detoxification of both nitric oxide (NO) and carbon monoxide (CO) gases by redox reaction. The synthesised catalysts were characterised by X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy and Brunauer–Emmett–Teller. In our study, we discovered that when doped with not more than 5% concentration of Pd and Rh the catalytic activity of cupric oxide was found to be increased. These electron-rich metals have a promotional effect on the catalytic activity for detoxification reactions. Effect of partial pressures of O2 and CO on the CO–O2 and NO–CO redox reactions was studied. Chemisorption of CO and NO was investigated using pulse titrations. Pd-doped CuO gave good catalytic reaction and showed better reaction stability in the presence and absence of the moisture.