Iron and Copper Containing Oxygen Reduction Catalysts From Templated Glucose-Histidine

Nitrogen doped carbons loaded with non-precious transition metals are currently investigated as substitutes of Pt-based catalysts for oxygen reduction in polymer electrolyte fuel cells (PEMFCs). This paper reports the preparation of one kind of such catalysts using glucose/histidine mixtures added with Fe and Cu salts in the presence of silica gels as hard templating agent to increase carbon surface area. The resulting carbons contain nitrogen in amounts that depend on heating temperature (T = 600 and 900 degrees C) on the glucose/histidine molar ratio and, more weakly, on the relative Fe/Cu amount. Surface areas are a function of reactant concentration and heating temperature, whereas pore size and pore size distribution only depend on glucose/histidine molar ratio. Cyclic voltammetry results on oxygen reduction depend on Fe/Cu ratio, the best result both in terms of incipient oxygen reduction potentials and currents being observed on samples only containing Fe, with no Cu added.