Electrocatalytic Oxidation of Formic Acid on Pd-Co/Omc Catalysts Prepared By the Polyol Method

Direct formic acid fuel cells (DFAFC) have attracted considerable interest recently as portable power applications. This due to the lower crossover of the formic acid through the Nafion-based membrane, a higher kinetic activity and a higher voltage operation compared to direct methanol fuel cells. Pd-based catalysts possess superior performance in formic acid oxidation in DFAFC compared to Pt catalysts. Beside this, the addition of Co to Pd catalysts has been shown better tolerance of intermediates produced during formic acid oxidation that tend to poison it, which improves the catalytic activity and stability of the cell. However a poor dispersion state of Pd catalysts on the support is partially blamed for lowering catalyst activity in DFAFC. Thus in order to achieve a higher efficiency of the catalyst a well dispersed Pd-Co on the carbon support is mandatory.  In this study, ordered mesoporous carbon (OMC) is evaluated as support to prepare Pd-based electro-catalyst (PdCo/OMC) for formic acid electro-oxidation in acid electrolyte. Pd-Co/OMC was synthesized by the polyol reduction method and characterized through XRD, EDS, TEM and electrochemical techniques. The results shown that the OMC support improves the catalytic activity of the Pd-Co anode, which has been attributed to the tailoring of the OMC support that facilitates the mass transfer process during the reaction.