Nanostructured ultrathin catalyst layer with ordered platinum nanotube arrays for polymer electrolyte membrane fuel cells

Fabrication of novel electrode architectures with nanostructured ultrathin catalyst layers is an effective strategy to improve catalyst utilization and enhance mass transport for polymer electrolyte membrane fuel cells (PEMFCs). Herein, we report the design and construction of a nanostructured ultrathin catalyst layer with ordered Pt nanotube arrays, which were obtained by a hard-template strategy based on ZnO, via hydrothermal synthesis and magnetron sputtering for PEMFC application. Because of the crystallographically preferential growth of Pt (111) facets, which was attributed to the structural effects of ZnO nanoarrays on the Pt nanotubes, the catalyst layers exhibit obviously higher electrochemical activity with remarkable enhancement of specific activity and mass transport compared with the state-of-the-art randomly distributed Pt/C catalyst layer. The PEMFC fabricated with the as-prepared catalyst layer composed of optimized Pt nanotubes with an average diameter of 90(110) nm shows excellent performance with a peak power density of 6.0 W/mg(pt) at 1 A/cm(2), which is 11.6% greater than that of the conventional Pt/C electrode. (C) 2019 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.