Enhanced methanol electrooxidation over defect-rich Pt-M (M = Fe, Co, Ni) ultrathin nanowires

How to improve the intrinsic activity of the Pt catalysts is still a pivotal issue in direct methanol fuel cells. Here, we prepared ultrathin Pt-M (M = Fe, Co, Ni) bimetallic networked nanowire using a soft template. These networked nanowires possess the one-dimension structural motif with a small diameter just around 2-3 nm and defect-rich surfaces (including grain boundaries, twin boundaries, and low-coordinated defects). Benefiting from the defect surface and electronic effect arising from the introduced transition metals, these Pt-M ultrathin nanowires (UNWs) exhibit enhanced electrocatalytic activity, CO tolerance, and stability toward methanol electrooxidation compared with monometallic Pt UNWs. In particular, due to the modified electronic structure from the appropriate content of Fe, Pt84Fe16 UNWs show 3.06-fold higher mass activity and 2.26-fold higher specific activity than those of Pt UNWs.