AUTHOR=Song Fujiao , Gao Jia , Yang Bairen , Cao Yan , Liu Huanhuan , Xu Qi TITLE=Cu2In alloy-embedded ZrO2 catalysts for efficient CO2 hydrogenation to methanol: promotion of plasma modification JOURNAL=Frontiers in Chemistry VOLUME=11 YEAR=2023 URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2023.1187762 DOI=10.3389/fchem.2023.1187762 ISSN=2296-2646 ABSTRACT=

Cu₁In₂Zr₄-O-C catalysts with Cu₂In alloy structure were prepared by using the sol–gel method. Cu₁In₂Zr₄-O-PC and Cu₁In₂Zr₄-O-CP catalysts were obtained from plasma-modified Cu₁In₂Zr₄-O-C before and after calcination, respectively. Under the conditions of reaction temperature 270°C, reaction pressure 2 MPa, CO₂/H₂ = 1/3, and GHSV = 12,000 mL/(g h), Cu₁In₂Zr₄-O-PC catalyst has a high CO₂ conversion of 13.3%, methanol selectivity of 74.3%, and CH₃OH space-time yield of 3.26 mmol/gcat/h. The characterization results of X-ray diffraction (XRD), scanning electron microscopy (SEM), and temperature-programmed reduction chemisorption (H₂-TPR) showed that the plasma-modified catalyst had a low crystallinity, small particle size, good dispersion, and excellent reduction performance, leading to a better activity and selectivity. Through plasma modification, the strong interaction between Cu and In in Cu₁In₂Zr₄-O-CP catalyst, the shift of Cu 2p orbital binding energy to a lower position, and the decrease in reduction temperature all indicate that the reduction ability of Cu₁In₂Zr₄-O-CP catalyst is enhanced, and the CO₂ hydrogenation activity is improved.