Hollow PtCo Nanowires with Rough Surfaces as Highly Active Electrocatalysts for Oxygen Reduction Reaction

Platinum-based nanowires/nanotubes electrocatalysts have a wide application for oxygen reduction reaction (ORR) in the fuel cells due to their remarkable electron transport capacity, ultra-high Pt utilization and stable one-dimensional structure, but their practical application is limited by catalytic activity and durability. In this paper, a one-pot two-step method for the synthesis of hollow PtCo nanowires (H-PtCo NWs) was reported. The Co nanowires with roughish surfaces synthesized by solvothermal method were used as sacrifice templates to form an intermediate of the Co@Pt NWs through incomplete galvanic replacement steps, and then the H-PtCo NWs were synthesized by subsequent etching process. XRD and TEM confirmed the presence of Pt and Co in H-PtCo NWs and the highly open one-dimensional structure. The ORR test showed the high ORR activity of H-PtCo NWs catalyst against the Co@Pt NWs and the Pt/C. The ORR durability of the H-PtCo NWs was demonstrated from the high retention of the ORR activity after ADTs. Therefore, the combination of one-dimensional characteristics, the alloying of Co element, the high exponent crystal plane and highly open struct of the H-PtCo NWs/C catalyst contributed to the remarkable ORR activity.