Facile one-step synthesis of porous PtPb neural network-like nanowires for electrooxidation of methanol with a CO-poisoning tolerance

Abstract

Porous one-dimensional Pt-based alloys with outstanding specific surface areas , short electron transport paths, and accessible Pt atoms are potential electrocatalysts for methanol oxidation reaction (MOR); however, their simple one-step synthesis for MOR remains a challenge. In this study, a simple one-step method is presented for the rational fabrication of PtPb porous nanowires (PNWs) by the direct autoclave of binary metal precursors in the mixed solvent of ethylene glycol and N,N -dimethylformamide at 170 ° C. The formation of PtPb PNWs is driven by the autocatalytic and Ostwald ripening growth mechanism with the assistance of ethylene glycol and N,N -dimethylformamide as a solvent, in situ template, and reducing agent. This method forms PtPb porous ultra-long (∼1.5 μm) neural PNWs with an average width of 20 nm enriched with abundant pores (5–10 nm), high Pb content (29 wt%), and decreased d-band level of Pt. These unique structural features enhanced the MOR mass (specific) activity of PtPb PNWs of 4.39 mA/μg Pt (49.3 mA/cm 2 ) by 4.5 (9.6) and 5.5 (35.0) times than those of Pt PNWs and Pt/C catalyst, respectively besides higher durability and CO-tolerance. The MOR activity of PtPb PNWs was among the highest reported binary porous Pt-based catalysts, which may promote the preparation of other Pt alloys PNWs for MOR. • Porous PtPb neural nanowires (PNWs) were prepared by a simple one-step method. • The formation mechanism of PtPb PNWs was underlined using various analyses. • The methanol oxidation performance of PtPb PNWs was superior to other PtPb. • The mass activity of PtPb PNWs was higher than Pt PNWs and Pt/C catalysts.