Methanol tolerant Pd-Based carbon supported catalysts as cathode materials for direct methanol fuel cells

Abstract

Alcohol crossover and the sluggish oxygen reduction reaction (ORR) at the cathode are the main practical drawbacks of direct methanol fuel cells (DMFCs). The current work attempts to disclose and compare several strategies to study the factors affecting the performance of DMFCs. With this end in view, kinetic and mechanistic parameters of several carbon-supported palladium–based electrocatalysts towards the ORR in 0.5 M H2SO4 and in 0.5 M H2SO4 + X M CH3OH (X = 0.5–3.0), were investigated applying rotating-ring disc electrode (RRDE) technique. Several procedures were employed and compared to scrutinize the data acquired during ORR in presence and absence of CH3OH. Furthermore, the first derivative method as practical way to determine the methanol tolerance is reported. It was found that PdFeIr/C exhibits the highest catalytic performance for the ORR in the absence and the presence of methanol, in comparison to PdIr/C, PdFe/C and Pd/C electrocatalysts.