Electrochemical synthesis of novel structured catalysts for H2 production

Innovative catalysts supported on metallic foams (FeCrAlloy) have been prepared by electrochemical synthesis of Ni-containing hydrotalcite-type (HT) films, and used in the steam methane reforming. It consisted of a one-step synthesis and deposition of HT compounds on metallic supports after the application of a cathodic potential on the foam. The effects of synthesis parameters, applied potential (0.9 and 1.2 V) and time (600, 1000 and 1800 s), on the properties of the supported films and catalytic performances were investigated. The potential applied mainly affected the rate of the basic media generation in the vicinity of the electrode, which is responsible for the precipitation of the HT compounds. The pulse length was the key factor to determining both the coverage of the support and the thickness of the film. Moreover, the Ni- and Al-content in the catalyst depended on both factors. The synthesis conditions affected the steam reforming tests performed under industrial-type conditions. The selection of optimum synthesis conditions (1.2 V for 1000 s) led to a well-adhered catalyst film, showing catalytic performances close to the thermodynamic equilibrium and stable with increasing time-on-stream. Furthermore, this preparation method offers the opportunity to develop processes with increasing chemico-energetic efficiency of endothermic reactions.