Fast synthesis and electrocatalytic activity of M@Pt (M = Ru, Fe3O4, Pd) core–shell nanostructures for the oxidation of ethanol and methanol

We report the fast synthesis and electrochemical evaluation of M@Pt core–shell nanostructures (M = Ru, Fe3O4, Pd) as well as Pt-alone nanoparticles for the ethanol and methanol oxidation reactions (EOR and MOR, respectively) in H2SO4 solution. The cores were obtained in 60 s. The Pt shells were deposited afterward on the cores also in 60 s. The reducing agent was NaBH4. XRD results showed that crystalline Pd, Fe3O4 and Pt materials were obtained from this rapid process, while Ru was formed as a quasi-amorphous structure. The average particle sizes of the core–shell nanostructures determined with the Scherrer equation, ranged from 7.35 to 9.29 nm. The electrochemical characterization revealed a catalytic activity of the novel Fe3O4@Pt anode as high as that of Ru@Pt for the EOR, and higher than the activity of Pt-alone. However, the Fe3O4@Pt catalysts showed a lower activity for the MOR than Ru@Pt and Pt-alone. Durability tests indicated a high electrochemical stability of the Fe3O4@Pt and Ru@Pt nanostructures.

► Core–shell nanostructures were synthesized by a fast process of 60 s.
► The novel Fe3O4@Pt core–shell anode showed a high catalytic activity for the EOR.
► Fe3O4@Pt and Ru@Pt showed a high electrochemical stability in acid medium.
► The Fe3O4@Pt catalyst is a highly interesting candidate to be used in DAFCs.