In this paper, the methanation of carbon oxides (CO and CO 2 ) was studied as an interesting way to provide a renewable energy source of synthetic natural gas (SNG) simultaneously reducing the emission of greenhouse gases. 15 wt.% Ni-based catalysts supported on CeO 2 , Al 2 O 3 and Y 2 O 3 oxides were synthesized by solution combustion synthesis. Then, a second series on Ni/Y 2 O 3 catalysts was prepared with different Ni loading (7-35 wt.%). The physicochemical properties of the catalysts were characterized by N 2 -physisorption, XRD, H 2 -TPR, CO-chemisorption, TEM, UV-Vis DRS, XPS, and CO 2 -TPD. The effect of reaction temperature (250-500°C) was investigated under atmospheric pressure, space velocity (GHSV) of 10,000 h −1 , and stoichiometric reactants ratio of (H 2 -CO 2 )/(CO+CO 2 ) = 3. A 200 h stability test was also carried out at 350°C over the 25 wt.% Ni/Y 2 O 3 catalyst. It can be concluded that the nature of Ni-support interactions played a crucial role in enhancing CO and CO 2 hydrogenation at relatively low reaction temperature. Ni/CeO 2 catalyst deactivated rapidly due to coke deposition, while the formation of NiAl 2 O 4 spinel was the main reason of the lower activity of the Al 2 O 3 -supported system. Activity data for Ni/Y 2 O 3 catalysts were closely related to the degree of Ni dispersion as well as to the medium-strength basicity. Good anti-coking and anti-sintering ability were observed after 200 h of lifetime test over the 25Ni/Y 2 O 3 catalyst.

Polymer electrolyte fuel cell stacks assembled with Johnson Matthey Fuel Cells and SolviCore MEAs based on the Aquivion™ E79‐03S short‐side chain (SSC), chemically stabilised perfluorosulphonic acid membrane developed by Solvay Solexis were investigated at CNR‐ITAE in the EU Sixth Framework ‘Autobrane' project. Electrochemical experiments in fuel cell short stacks were performed under practical automotive operating conditions at pressures of 1–1.5 bar abs. over a wide temperature range, up to 130 °C, with varying levels of humidity (down to 18% R. H.). The stacks using large area (360 cm2) MEAs showed elevated performance in the temperature range from ambient to 100 °C (cell power density in the range of 600–700 mWcm–2) with a moderate decrease above 100 °C. The performances and electrical efficiencies achieved at 110 °C (cell power density of about 400 mWcm–2 at an average cell voltage of about 0.5–0.6 V) are promising for automotive applications. Duty‐cycle and steady‐state galvanostatic experiments showed excellent stack stability for operation at high temperature. A performance comparison of AquivionTM and NafionTM‐based MEAs under practical operating conditions showed a significantly better capability for the Solvay Solexis membrane to sustain high temperature operation.

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