CATHODIC ELECTROCATALYSTS TOLERANT TO METHANOL FOR DIRECT METHANOL FUEL CELL

摘要

The PtM electrocatalysts displayed higher activity than Pt/C electrocatalyst towards oxygen reduction reaction. PtCr catalyst having a nominal atomic ratio, as determined by EDX then corresponding to bulk composition and not surface composition, close to (0.8:0.2) showed higher activity for ORR in methanol-free oxygen saturated electrolyte and at low overpotentials in saturated oxygen electrolyte containing 0.1 M methanol. Results were confirmed under DMFC operating condition at 90 deg C. Iron phthalocyanine based cathodes were prepared either by dispersion of FePc on carbon or by electropolymerization of aniline in presence of FeTsPc. The macrocycles based cathodes were compared in a standard three-electrode electrochemical cell and under DMFC conditions at room temperature. The total insensitivity of such catalysts towards methanol was clearly demonstrated. It was also shown that the molecular dispersion of FeTsPc into a polyaniline (PAni) film greatly enhances the activity of the macrocycle catalyst towards oxygen reduction reaction (ORR).