Co/CeO2 for ethanol steam reforming: effect of ceria morphology

Nanorods (NR) and nanoparticles (NP) of ceria were prepared by hydrothermal synthesis method and used as catalyst support to load cobalt for steam reforming of ethanol (SRE). The catalysts were characterized by using temperature programmed reduction, X-ray diffraction, transmission electron microscopy and thermal analysis techniques. CeO2 NP had relatively smaller particle size and larger surface area, and CeO2 NR could form more oxygen vacancies. For SRE reaction, Co/CeO2 NP was more active and exhibited a little better anti-sintering ability, while Co/CeO2 NR showed obviously better anti-carbon deposition ability. The larger surface area and higher dispersion of cobalt oxide resulted in the higher activity for Co/CeO2 NP catalyst. Meanwhile, the stronger interaction between cobalt species and ceria was attributed to the better anti-sintering ability for Co/CeO2 NP. The improvement of the anti-carbon deposition for Co/CeO2 NR was owing to the generation of oxygen vacancies from the ceria nanorods.