With the increasing demand for highly efficient and durable catalysts, researchers have been doing extensive research to engineer the shape, size, and even phase (e.g., hcp or fcc Co) of individual catalyst nanoparticles, as well as the interface structure between the catalyst and support. In this work, cobalt oxides were deposited on ceria with rod-like morphology (CeO2NR) and cube-like morphology (CeO2NC) and silica with sphere-like morphology (SiO2NS) via a precipitation–deposition method to investigate the effects of support morphology, surface defects, support reducibility, and the metal–support interactions on redox and catalytic properties. XRD, Raman, XPS, BET, H2-TPR, O2-TPD, CO-TPD, TEM, and TPR/TPO cycling measurements have been mainly employed for catalysts characterization. Compared with CeO2NC and SiO2NS supports, as well as CeO2NC- and SiO2NS-supported cobalt catalysts, CeO2NR counterparts exhibited enhanced reducibility and CO oxidation performance at a lower temperature. Both the apparent activation energy and CO conversion demonstrated the following catalytic activity order: 10 wt % CoO x /CeO2NR > 10 wt % CoO x /CeO2NC > 10 wt % CoO x /SiO2NS. These results showed a strong support-dependent reducibility, CO oxidation, and redox cycling activity/stability of the as-prepared catalysts. Moreover, the significantly enhanced catalytic CO oxidation of the 10 wt % CoO x /CeO2NR catalyst indicated the vital role of CeO2NR support with rich surface oxygen vacancies, superior oxygen storage capacity and mobility, and excellent adsorption/desorption behavior of CO and O2 species.

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Low temperature steam reforming of ethanol in the temperature range of 200-360ºC was studied to maximize the production of H 2 . The optimum reaction conditions in presence of a suitable catalyst can produce mainly the desired products H 2 and CO 2 . Cu/Al 2 O 3 catalysts with six different concentrations ranging from 0 to 10 wt.% Mn, were prepared, characterized and studied for the ethanol-steam reforming reaction. Maximum ethanol conversion of 60.7% and hydrogen yield of 3.74 (mol H 2 / mol ethanol converted) were observed at 360ºC for catalyst with 2.5 wt.% Mn loading.On a étudié le reformage de l'éthanol à la vapeur à basse température dans la gamme de températures de 200-360 ºC afi n de maximiser la production de H 2 . Les conditions de réaction optimales en présence d'un catalyseur adéquat peuvent produire principalement les produits désirés soient H 2 et CO 2 . Des catalyseurs de Cu/Al 2 O 3 à six concentrations différentes variant de 0 à 10 % en masse de Mn, ont été préparés, caractérisés et étudiés pour la réaction de reformage de l'éthanol à la vapeur. Une conversion d'éthanol maximum de 60,7 % et un rendement d'hydrogène de 3,74 (H 2 mol/éthanol converti mol) ont été obtenus à 360 ºC pour un catalyseur ayant une charge de Mn de 2,5 % en masse.

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