Interfacial engineering of PProDOT-modified Fe-NCNT supports for high-efficiency Pt electrocatalysts toward methanol oxidation reaction

The development of platinum (Pt)-based electrocatalysts with optimized interfacial structures is crucial to improve the efficiency of direct methanol fuel cells (DMFCs). Here, a Pt-based methanol oxidation reaction (MOR) catalyst (Pt/PProDOT/Fe-NCNT) is constructed by anchoring Pt to poly(3,4-propylenedioxythiophene) (PProDOT) modified and Fe/N co-doped carbon nanotubes (Fe-NCNT) via interfacial engineering. The mass activity (MA) of the Pt/PProDOT/Fe-NCNT catalyst (1258.9 mA mg −1 ) was higher than that of the Pt/Fe-NCNT catalyst (661.5 mA mg −1 ), suggesting that the introduction of PProDOT over Fe-NCNT may enhance the catalytic activity and accelerate the reaction kinetics. The MA value of the Pt/PProDOT/Fe-NCNT catalyst was also superior to that of the commercial Pt/C (282.8 mA mg −1 ) catalyst and many other reported Pt-based catalysts. Experiments and material characterization show that the synthesized Pt/PProDOT/Fe-NCNT catalyst has a unique bamboo-like hollow structure and is cross-linked to form a three-dimensional network. Such a structure can lead to more chemically active sites by the electronegative N atoms in Fe-NCNT, while stabilizing the Pt nanoparticles by the S atoms in PProDOT. Furthermore, the stacking of π-π rings between PProDOT and Fe-NCNT facilitates electron conduction, thereby enhancing catalytic activity and MOR efficiency. Results from this study offer a possible new design of Pt-based catalyst with polymer-modified carbon carriers.