Pt–Co intermetallic nanoparticles anchored on nitrogen-rich graphene for efficient oxygen reduction reaction in acid

Pt-based intermetallic nanoparticles demonstrate impressive oxygen reduction reaction (ORR) activity and durability due to their atomically ordered nature but their synthesis remains a tremendous challenge. Herein we report Pt–Co intermetallic nanoparticles anchored on nitrogen-rich graphene (NG) nanosheets for efficient ORR electrocatalysis in acidic media. The rich nitrogen atoms, doped via low-temperature plasma treatment on graphene efficiently inhibit the sintering of the nanoparticles during high temperature annealing via strong metal-support interaction and enhance the anchoring stability. Meanwhile, the electronic interaction between NG and Pt–Co intermetallic nanoparticles negatively shifts the d-band center of Pt to enhance their intrinsic ORR activity. As-prepared PtCo/NG-900 with low Pt loading of 3.4 μg cm −2 exhibits high mass activity of 1.28 A mg −1 at 0.8 V vs. RHE, and enhanced durability with only 1.9 mV decay in half-wave potential (E 1/2 ) after 2000 potential cycles.