The methanol oxidation reaction on platinum alloys with the first row transition metals: The case of Pt–Co and –Ni alloy electrocatalysts for DMFCs: A short review

In recent years there has been much activity in examining Pt alloys with first row transition metals as catalysts materials for DMFCs. In this work, the electrochemical oxidation of methanol on Pt–Co and –Ni alloy electrocatalysts is reviewed. The effect of the transition metal on the electrocatalytic activity of Pt–Co and –Ni for the methanol oxidation reaction (MOR) has been investigated both in half-cell and in direct methanol fuel cells. Conflicting results regarding the effect of the presence of Co(Ni) on the MOR are examined and the primary importance of the amount of non-precious metal in the catalyst is remarked. For low base metal contents, an enhancement of the onset potential for the MOR with increasing Co(Ni) amount in the catalyst is observed, whereas for high contents of the base metal, a drop of the MOR onset potential with increasing Co(Ni) is found. As well as the base metal content, an important role on the MOR activity of these catalysts has to be ascribed to the degree of alloying.