Heterogeneous nanocomposites consisting of Pt3Co alloy particles and CoP2 nanorods towards high-efficiency methanol electro-oxidation

Heterogeneous nanocomposites comprising chemically distinct constituents are particularly promising in electrocatalysis. We herein report a synthetic strategy that combines the reduction of Pt and Co ionic precursors at an appropriate ratio with the subsequent phosphating at an elevated temperature for forming heterogeneous nanocomposites consisting of quasi-spherical Pt3Co alloy domains and rod-like CoP2 domains for high-efficiency methanol electro-oxidation. The strong electronic coupling between Pt3Co and CoP2 domains in the nanocomposites render the electron density around Pt atoms to decrease, which is favorable for reducing the adsorption of poisoning CO-like intermediates on the catalyst surfaces. Accordingly, the as-prepared heterogeneous Pt3Co-CoP2 nanocomposites show good performance for methanol electro-oxidation both in acidic and alkaline media. In specific, at a Pt loading of only 6.4% on a common carbon substrate, the mass-based activity of Pt3Co-CoP2 nanocomposites in an acidic medium is about 2 and 1.5 times as high as that of commercial Pt/C catalyst (20% mass loading) and home-made Pt3Co alloy nanoparticles (8.0% mass loading), while in the alkaline medium, these values are 3 and 2, respectively.

Automated summary

This study reports a synthetic strategy to prepare heterogeneous Pt3Co-CoP2 nanocomposites with high performance for methanol electro-oxidation. The nanocomposites exhibit strong electronic coupling between Pt3Co and CoP2 domains, resulting in decreased electron density around Pt atoms, which is beneficial for reducing the adsorption of poisoning CO-like intermediates on catalyst surfaces. The as-prepared Pt3Co-CoP2 nanocomposites show superior mass-based activity compared to commercial Pt/C catalyst and homemade Pt3Co alloy nanoparticles in both acidic and alkaline media.