Corporate Research & Development Center

Development of Low-Platinum-Loaded Electrocatalyst for Polymer Electrolyte Fuel Cells

Polymer electrolyte fuel cells (PEFCs), which have excellent features including compactness and highcurrent-density operation, have already been utilized in the ENE-FARM residential fuel cell system, and their full-fledged dissemination in PEFC-based fuel cell vehicles is expected in the near future.

The conventional PEFC cathode electrocatalyst is generally based on a structure called platinum-oncarbon (Pt/C), consisting of nanoparticles of Pt that are supported by or loaded on larger C particles. It is technically challenging to reduce the amount of Pt without compromising the durability of the fuel cell.

As a solution to this issue, Toshiba has developed a unique electrocatalyst synthesis process using a sputtering method to produce a thin Pt catalyst layer. From the results of galvanodynamic polarization testing, it was determined that the start-stop durability and per-site specific activity of the new electrocatalyst are double those of the conventional Pt/C catalyst.

ENE-FARM is a trademark of Tokyo Gas Co., Ltd., Osaka Gas Co., Ltd., and Nippon Oil Corporation.

Newly developed catalyst layer

Cross-sectional scanning electron microscope (SEM) images of newly developed and conventional Pt/C catalyst layers

Conventional Pt/C catalyst layer

Cross-sectional scanning electron microscope (SEM) images of newly developed and conventional Pt/C catalyst layers

Cross-sectional scanning electron microscope (SEM) images of newly developed
and conventional Pt/C catalyst layers