Fabrication of Pt3Ni catalysts on polypyrrole-modified electrochemically exfoliated graphene with exceptional electrocatalytic performance for methanol and ethanol oxidation

Abstract Electrochemically exfoliated graphene is deemed as a good catalyst support owing to less functional groups and defects on its surface. However, its inert surface is not conducive to the in-situ growth of catalysts. In this work, electrochemically exfoliated graphene is modified by polypyrrole to increase the surface active sites for growing catalyst nanoparticles. Moreover, to reduce the consumption of rare Pt metal as well as raise its electrocatalytic activity, Pt3Ni alloy catalysts are prepared on its surface. It is worth mentioning that polypyrrole not only serves as a linker to immobilize and disperse Pt3Ni nanoparticle on EEG, but also promotes the poison tolerance of Pt3Ni catalysts by donating electrons. Therefore, the electrocatalytic performance of Pt3Ni catalysts for methanol and ethanol oxidation are highly improved after polypyrrole modification. The optimum ratio of Pt to Ni in Pt–Ni alloy is also studied and the results show that Pt3Ni catalysts exhibit better electrocatalytic performance than other PtxNi alloys (x = 1, 2, 4). The novel strategy that using polypyrrole to modify electrochemically exfoliated graphene may advance the application of electrochemically exfoliated graphene as a new generation catalyst support.