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SiO 2 and ZrO 2 supported Ni catalysts were prepared for the steam reforming of ethanol. The catalytic performances, in terms of both H 2 productivity and stability towards coking and sintering, were related to the physico-chemical properties of the catalysts. The samples were prepared either by synthesis of the support by precipitation and subsequent impregnation with the active phase, or by direct synthesis through flame pyrolysis (FP). The latter has been chosen because it leads to nanostructured oxides, characterised by high thermal resistance, important for this high temperature application.The samples showed different textural, structural and morphological properties, as well as different reducibility and thermal resistance, depending on the preparation method and support.One of the key parameters governing the final catalyst properties was metal-support interaction. In particular, the stronger the latter parameter, the higher was metal dispersion, leading to small and stable Ni clusters. This influenced both activity and the resistance towards coking.Surface acidity was also taken into account considering the effect of the different nature of acid sites (silanols or Lewis a.s.) of both support and metal phase on catalyst deactivation.The best results were obtained with a 10 wt% Ni/SiO 2 sample, prepared by FP, when tested at 625°C. H 2 productivity of 1.44 mol H 2 /min kg cat was reached, corresponding to ca. 80% of the maximum value achievable under the selected conditions. This result was accompanied by the lowest CO/CO 2 ratio, which simplifies H 2 purification steps for use in fuel cells, and 100% carbon balance without by-products in the outflowing gas.

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Ni‐based catalysts supported on TiO2, ZrO2 and SiO2 (in the form of mesoporous Santa Barbara Amorphous 15 (SBA‐15) and amorphous dense nanoparticles), were employed in the steam reforming of glycerol. Each sample was prepared by liquid phase synthesis of the support followed by impregnation with the active phase and calcination at 800 °C or by direct synthesis through flame pyrolysis. Many techniques have been used to assess the physical chemical properties of both the fresh and spent catalysts, such as atomic absorption, N2 adsorption/desorption, XRD, SEM, TEM, temperature‐programmed reduction (TPR), X‐ray photoelectron spectroscopy (XPS), Micro‐Raman and FTIR spectroscopy. The samples showed different textural, structural and morphological properties, as well as different reducibility and thermal resistance depending on the preparation method and support. Some of these properties were tightly bound to catalyst performance, in terms of H2 productivity and stability towards coking and sintering. A key parameter was the metal–support interaction, which strongly depended on the preparation procedure. In particular, the stronger the interaction, the more stable the metallic Ni clusters, which in turn lead to a higher catalytic activity and stability. Surface acidity was also taken into account, in which the nature of the acid sites was differentiated (silanols, titanols or Lewis acid sites). The characterisation of the spent catalysts also allowed us to interpret the deactivation process. The formation of multi‐walled nanotubes was observed for every sample, though it was only in some cases that this led to severe deactivation.