Copper as promoter of the NiO–CeO 2 catalyst in the preferential CO oxidation

Heterogeneous Cu–Fe oxide catalysts for preferential CO oxidation (PROX) in H2-rich process streams

“…As reported in the literature, the presence of CO 2 acts to disrupt the reaction mechanism due to alteration of the dissemination of the products adsorbed on metal oxide catalysts. 7,45,46 The present results also showed that the presence of CO 2 has a superior effect on hydrogen oxidation so that the CO conversion decreases (Fig. 6).…”

Synthesis and characterization of nickel-doped ceria nanoparticles with improved surface reducibility

“…17 Two addition features are observed at about 545 and 620 cm À1 which according to previous studies are induced by defects in the ceria structure. 16,18 The lower-wavenumber band at 545 cm À1 is attributed to defect sites that include an O 2À vacancy (extrinsic vacancy), while the higher-wavenumber band at 620 cm À1 is induced by the presence of Ce 3+ or Ni 3+ ions. 16,[18][19][20] The peak at 225 cm À1 is the transverse optical (TO) phonon mode, which, it becomes Raman active due to the disorder induced by doping in CeO 2 .…”

Highly Efficient Removal of CO in Effluent Streams from Real‐Life Propane Oxidation Process over CuO−CeO2−Based Catalysts

“…Laser Raman spectra on the mixed metal oxides, together with those of pure CeO 2 and pure Co 3 O 4 , were presented in Figure , employing the laser wavelength of 532 nm. From the feature of Raman spectra, pure CeO 2 sample shows an intense main peak at around 462 cm −1 , which is assigned to the F 2g mode of fluorite ,. Pure Co 3 O 4 spectroscopy shows typical Raman modes of the spinel structure located at 475, 516, 615 and 680 cm −1 ,.…”

“…However, CeO 2 −Co 3 O 4 sample displayed poorer CO oxidation activity and CuO−Co 3 O 4 catalyst was even inactive at temperature lower than 160 °C. It has been reported that the presence of a certain amount of copper oxide incorporated in ceria may induce a higher redox activity at the interface, in which a synergistic interaction between Cu and oxygen vacancies provided by CeO 2 is responsible for the generation of highly active sites on the Cu/Ce interface . It means that CO oxidation may occur primarily on active sites at the copper‐ceria interface, In addition, the reference catalyst Pt/FeO x exhibited the more excellent activity for CO conversion at the lower temperature than 100 °C.…”