(617ej) Connected Nanoparticle Catalysts Having a Porous, Hollow Capsule Structure As Carbon-Free Electrocatalysts for Polymer Electrolyte Fuel Cells

Yamaguchi, T., Tokyo Institute of Technology
Kuroki, H., Kanagawa Academy of Science and Technology
Tamaki, T., Tokyo Institute of Technology

We developed connected
carbon-free platinum-iron (PtFe) nanoparticle catalysts
with porous hollow capsule structure (Fig. 1) as oxygen-reduction-reaction
(ORR) electrocatalysts for polymer electrolyte fuel
cells (PEFCs).[1] This catalysts
consist of a beaded network by connected PtFe
nanoparticles with a crystallite size of 6~7 nm and a chemically-ordered (face centered
tetragonal) superlattice structure. The beaded
network is electrically conductive; thus, carbon-supports can be removed from
catalyst layers in PEFCs. We have demonstrated that an MEA prepared using a
carbon-free cathode of connected PtFe-nanoparticle
catalysts was highly durable against start-up/shut-down operations because of
the elimination of carbon-corrosion problems.Moreover, an ORR specific
activity of a connected PtFe catalyst is about 9 times
higher than that of a commercial Pt-nanoparticle
catalyst supported on carbon black (Pt/C). Recent
results will be explained.

[1] T. Tamaki, H. Kuroki, S. Ogura, T. Fuchigami, Y. Kitamoto, and T.
Yamaguchi, Energy Environ. Sci., 8,
3545-3549 (2015)

à–¾: Macintosh HD:Users:Takeo:Desktop:Capsule.pdf

Fig. 1.
Schematic illustration and TEM images of a carbon-free connected PtFe-nanoparticle catalyst with porous hollow capsule
structure and its ORR activity compared with catalysts on carbon.