Supportless Pt and Pt-Pd Nanotubes with High Durability and Activity Towards Oxygen Reduction Reaction for PEMFCs

A new class of cathode catalysts based on supportless Pt nanotubes (PtNTs) and Pt alloy nanotubes with remarkable durability and high catalytic activity have been developed. Due to their unique combination of dimensions at multiple length scales, the PtNTs can provide high Pt surface area by their nanometer-sized wall thickness and have the potential to eliminate or alleviate most of the degradation pathways of the commercial carbon supported Pt catalyst (Pt/C) and unsupported Pt black as a result of their micrometer-sized length. The PtNTs asymptotically approaches a maximum of ~20% Pt surface area loss in durability test, while the commercial PtB and Pt/C loses about 51% and 90% of their initial surface area, respectively. Moreover, the PtNTs and PtPdNTs show much higher specific activity than commercial Pt/C.