Tailoring the electronic structure of PtNi nanoalloy for boosting methanol electro-oxidation reaction

Abstract

Tailoring the electronic structure of Pt-based catalysts can effectively facilitate their methanol oxidation reaction (MOR). Despite a great deal of effort, the fabrication of Pt-based catalysts with both tunable electronic structure and well-dispersion is still challenging. Herein, the PtNi alloy nanoparticles supported on poly (3, 4-ethylenedioxythiophene) modified multi-walled carbon nanotubes (PtNi/PEDOT-MWCNTs) was prepared for MOR. Transmission electron microscopy reveals the successful synthesis of PtNi nanoparticles (3.5 nm) by the reduction of H2. The X-ray photoelectron spectroscopy confirmed the strong electronic interaction between Ni and Pt, and the electronic environment of Pt atoms can be tailored by alloying different atomic content of Ni. Thus, the obtained PtNi/PEDOT-MWCNTs was suitable to design an effective electro-catalyst. As revealed through the electrochemical measurements, the fabricated PtNi/PEDOT-MWCNTs catalyst displayed higher peak current density, better stability, and excellent CO-tolerance than those of Pt nanoparticles dispersed on PEDOT-MWCNTs, MWCNTs, and commercial carbon black. The surface/interface engineering tactic highlights the tailoring of the electronic structure of Pt-based catalysts, which can be applied in various fields, including methanol fuel cells and other catalytic reactions.