High efficient CuCeO2-δ/SiO2 catalyst for RWGS reaction: impact of Ce content and loading sequence

Abstract

The extensive use of fossil energy leads to wanton emission of CO₂ and serious environmental problems. The exploration of high-performance catalysts plays a pivotal role in CO₂ resource utilization. In this paper, CuCe_yK catalysts are prepared by wet impregnation method using ordered mesoporous SiO₂ as support for the reverse water gas shift (RWGS) reaction. The physicochemical properties of the prepared catalysts are characterized by H₂-TPR, BET, XRD, Quasi in-situ XPS, H₂-TPD, and CO₂-TPD techniques. The results demonstrate thatthe Cu⁰ species can form synergistic effects with oxygen vacancies (O_v) to enhance the CuCe_yK catalytic performance. Additionally, the electronic effects between Ce and Cu not only enhances the adsorption and activation performances of the catalyst towards CO₂ and H₂ molecules, but also effectively suppresses the sintering of Cu⁰ species, thereby enhancing the stability of the corresponding catalyst. It is worth mentioning that the Ce content also directly affects the catalytic performances of the CuCe_yK catalyst. The CuCe₁₅K catalyst with a Ce content of 15% displays excellent CO₂ hydrogenation performances, and the CO₂ conversion and CO selectivity up to 41 % and 100 % at 420 °C, respectively. © 2024 Society of Chemical Industry and John Wiley & Sons, Ltd.