Synthesis and characterization of pure and (Ce, Zr, Ag) doped mesoporous CuO-Fe2O3 as highly efficient and stable nanocatalysts for CO oxidation at low temperature

Abstract

A series of single and mixed oxide nanocatalysts of mesoporous CuO-Fe2O3 with different CuO contents (1–50wt.%) were prepared by a co-precipitation method and further promoted by trace amounts of CeO2, ZrO2 and Ag2O (0.1–0.5wt.%) dopants. The original and calcined catalysts were characterized by TG, DTA, XRD, TEM, VSM, N2 sorption analysis, surface chemisorbed oxygen and DC electrical conductivity measurements. The catalytic performance of these nanocatalysts toward CO oxidation was studied using a conventional fixed bed flow type reactor. The results revealed that the addition of 1–20wt.% CuO to Fe2O3 monotonically increases the specific surface area, the amount of surface chemisorbed oxygen, electrical conductivity and catalytic activity of the nanocatalysts. In addition, the catalytic activity indicated that Fe-Cu mixed oxide nanocatalyst promoted with the three dopants (CeO2, ZrO2 and Ag2O) exhibited the highest catalytic activity with a total conversion of CO into CO2 at 100°C. Moreover, the activation energy of CO oxidation decreased from 38.4 to 23.1kJmol−1 upon treating the catalyst containing 20wt.% CuO with the three dopants. Finally the effects of various operational parameters were also studied.