Prompt template-free synthesis of porous PtPb sponge-like nanostructure for electro-oxidation of methanol and carbon monoxide

Porous Pt-based alloys entail earth-abundant and low-cost metal, not only contribute to the rational consumption of expensive and rare Pt metal but also the enhancement of its activity towards the methanol electro-oxidation reaction (MEOR). Herein, a porous sponge-like PtPb alloy was synthesized by using the ice-reduction method driven by the coalescence growth mechanism under the intensive reduction power of borohydride. The presented PtPb sponge nanostructure was prepared using a facile, one-step method without heating or surfactants. Meanwhile, PtPb had a sponge-like shape with accessible active sites, a high surface area, abundant pore volume (0.05 cm³/g), pore size (2–20 nm), Pb loading (13.0 at.%), and an upshifted d-band center of Pt. These inimitable structural and compositional merits endow the electro-oxidation of methanol with a higher mass (specific) activity of 0.907 mA/µg_Pt (5.7 mA/cm²) compared to those of Pt sponge-like nanostructure and Pt/C catalyst by 1.47 (1.35) and 1.72 (8.51) times, respectively, besides higher durability. Moreover, PtPb had higher activity and durability towards the electro-oxidation of carbon monoxide (CO) than Pt and Pt/C. The proposed study may provide new insights into the simple synthesis of a Pt-based alloy for the electrocatalytic oxidation of small organic molecules.