Dependence of the CeO2 morphology in CuO/CeO2 catalysts for the oxidative steam reforming of methanol

Copper oxide on ceria supports (CuO/CeO2) were investigated as catalysts for the oxidative steam reforming of methanol (OSRM) reaction at 200–400 °C. Different shapes of CeO2 were obtained, as rod-, mixed- (rod and cube) and cube-shaped with an exposed surface of (110) + (100), (110) + (100) and (100) planes by variation in the hydrothermal synthesis temperature (100–220 °C). The CuO was deposited on CeO2 by deposition–precipitation at a nominal 10% by weight and the obtained CuO/CeO2 catalysts were characterized. The morphological structure of CeO2 influenced the catalytic activities in the OSRM reaction. The CuO/rod-shaped CeO2 (CuO/CeO2-R) gave the highest turnover frequency (TOF) and a CO concentration of less than 1% (v/v). The high catalytic performance of CuO/CeO2-R involved the well-dispersed CuO nanoparticles, level of Cu+ species as the active site, improved reducible oxide, number of relative oxygen vacancies and the stronger interaction between CuO and CeO2.