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Mesoporous carbon structures containing copper particles were synthesized according to different synthesis methods in order to tune the morphostructural properties of these electrocatalysts for the CO2 reduction reaction. Microwave polyol synthesis, hard templating, one pot soft templating and evaporation induced self assembly gave access to different mesoporous structures. Copper particles were identified inside the mesoporous structures, while the porous channels remained unaffected leading to confined nano reactors. Bulk electrolyses showed that only two CO2 reduction products are obtained: HCOOH as the main product with a low amount of CO, H2 completing the faradaic balance. Differences in steady state current densities during electrolyses were correlated to the Cu metallic specific surface area. The latter was determined according to a geometrical model based on truncated octahedron clusters developed for copper clusters. This correlation evidences that confined Cu particles remains still electroactive and paves a way for the efficient development of 3D electrodes.

Palladium-based and gold nanomaterials were synthesized by the so-called "Bromide Anion Exchange" method. This soft and clean synthetic route leads to well dispersed small nanoparticles on carbon support. Accordingly, these nanoscale structures have a high active surface area like 81 m2 g-1 for the 20 wt.% Pd/C electrocatalyst. The CO stripping experiments performed in alkaline medium have highlighted the dependence of the CO adsorption mode on palladium. When used as anode for glycerol or glucose electrooxidation in alkaline medium, they exhibit good activities. Moreover, the bimetallic catalysts showed an important improvement of the kinetics at lower potentials when compared to Pd/C. Some added value products like glycerate or glycolate have been detected by chromatographic analysis. These nanomaterials are promising electrodes in fuel or hybrid biofuel cell devices in a cogeneration of high value chemicals and energy process

Mesoporous carbon structures containing copper particles were synthesized according to different synthesis methods in order to tune the morphostructural properties of these electrocatalysts for the CO2reduction reaction. Microwave polyol synthesis, hard templating, one pot soft templating and evaporation induced self assembly gave access to different mesoporous structures. Copper particles were identified inside the mesoporous structures, while the porous channels remained unaffected leading to confined nano reactors. Bulk electrolyses showed that only two CO2reduction products are obtained: HCOOH as the main product with a low amount of CO, H2completing the faradaic balance. Differences in steady state current densities during electrolyses were correlated to the Cu metallic specific surface area. The latter was determined according to a geometrical model based on truncated octahedron clusters developed for copper clusters. This correlation evidences that confined Cu particles remains still electroactive and paves a way for the efficient development of 3D electrodes.

Ru and Ir based materials were prepared by the thermal decomposition of polymeric precursor's method. The anode catalysts free from carbon substrate were obtained by tailoring the reaction process to avoid occurrence of CO2formation during water electrolysis. Various Ir contents were added in the Ru catalytic compositions for improving the oxidation-resistance of RuO2which was the best metallic oxide in H2O splitting. Their physical characterizations revealed the presence of agglomerates due probably to the heat treatment process consisting in the removal of organic carbon at 400 ºC. The prevalent existence of RuO2 and IrO2 in the anode materials was confirmed by XPS experiments and the electrochemical measurements enabled to show that RuxIr1-xO2materials were more active towards water oxidation than IrO2catalyst. The O2evolution process started at 1.45 V with Ru0.9Ir0.1O2in the anodic compartment of a 25 cm2Proton Exchange Membrane Water Electrolyzer at 60ºC.