CuIn alloy-embedded ZrO catalysts for efficient CO hydrogenation to methanol: promotion of plasma modification.

CuInZr-O-C catalysts with CuIn alloy structure were prepared by using the sol-gel method. CuInZr-O-PC and CuInZr-O-CP catalysts were obtained from plasma-modified CuInZr-O-C before and after calcination, respectively. Under the conditions of reaction temperature 270°C, reaction pressure 2 MPa, CO/H = 1/3, and GHSV = 12,000 mL/(g h), CuInZr-O-PC catalyst has a high CO conversion of 13.3%, methanol selectivity of 74.3%, and CHOH 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 (H-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 CuInZr-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 CuInZr-O-CP catalyst is enhanced, and the CO hydrogenation activity is improved.