Solvothermal synthesis in ethylene glycol and catalytic activity for CO oxidation of CuO/CeO2 catalysts

Abstract

A series of supported CuO/CeO 2 catalysts with various CuO loadings (5-25 wt%) were prepared using a solvothermal method with ethylene glycol as solvent. The effects of CuO loading on physicochemical properties and catalytic activity of the prepared CuO/CeO 2 catalysts have been investigated by X-ray diffraction, Raman spectroscopy, BET surface area measurement, X-ray photoelectron spectroscopy, temperature-programmed reduction with H 2 , temperature-programmed desorption of CO techniques, and low-temperature CO oxidation reaction test.The results indicate that the catalyst with 10 wt% CuO loading has the highest catalytic activity, which can be attributed to the largest amounts of well-dispersed CuO species strongly interacting with support CeO 2 and oxygen vacancies caused by the incorporation of Cu 2? into CeO 2 lattice, and the highest concentration of and the most active lattice oxygen. The activity for CO oxidation of the supported CuO/CeO 2 catalyst prepared by the present solvothermal method was significantly higher than that of the counterparts prepared by the commonly used impregnation and deposition-precipitation methods.

High Oxygen Reduction Reaction Performances of Cathode Materials Combining Polyoxometalates, Coordination Complexes, and Carboneous Supports

“…Focusing first on the Cu 6 Ni 7 /TTF-F material, its XPS survey spectra show Cu, Ni, P, and W signals, in contrast to those of TTF-F and in line with the presence of Cu 6 Ni 7 POMs. To be specific, the XPS peaks of Cu element at ∼951–957 and ∼930–938 eV are assigned to Cu 2p 1/2 and Cu 2p 3/2 , respectively (Figure a). − Relatively weak Cu II satellite peaks at ∼940–947 and ∼958–965 eV are also noted. The Ni 2p XPS spectrum can be deconvoluted into one spin–orbit coupling and two shakeup satellites located at ∼862.8 and ∼880.8 eV.…”

CO oxidation over Cu-Ce binary oxide prepared by solvothermal method: Effects of cerium precursors on the properties and catalytic behavior

“…Generally, two factors can affect the lattice constants of CeO 2 . On the one hand, the radius of Cu 2+ (0.072 nm) is smaller than that of Ce 4+ (0.097 nm), which leads to lattice contraction when Cu 2+ replaces part of Ce 4+ into the lattice (Zheng et al 2016). On the other hand, the formation of oxygen vacancies due to the substitution of Ce 4+ by Cu 2+ or the formation of Ce 3+ (0.103 nm) will have the opposite effect on the lattice of CeO 2 (Hossain et al 2018).…”

“…Up to now, the most widely investigated catalysts for CO oxidation are supported noble metals and supported or mixed transition metal oxides. Because of the drawbacks of precious metal catalysts with limited resources and high cost, transition metal oxides, especially Cu-Ce composite oxides, have been widely studied due to their high catalytic activity in CO oxidation reaction, low price, and abundant resources (Zheng et al 2016;Chen et al 2020). Although much research has been done on the Cu-Ce composite oxide catalyst and some progress has been made over the past decades, it still has the disadvantages of low activity and poor resistance to water or CO 2 at low temperatures, which limit its practical application (Zhang et al 2019;Cui et al 2019).…”

Highly active nano-composite of cobalt–copper–manganese oxides for room temperature CO oxidation

“…This variation in CuO was clearly highlighted from the XRD pattern of a composite oxide. Likewise, it has been widely accepted that the presence of the CuO phase in solid material displays a high affinity toward the CO, thus adsorbing more CO on the surface (Hutchings et al 1996;Martínez-Arias et al 2000;Zheng et al 2016).…”