Investigation of Carbon Nanofibers as Catalyst Support for Fuel Cell Electrodes

Abstract

Cathodes for fuel cells with platinum as catalyst supported on tubular carbon nanofibers (CNFs) were investigated for the oxygen reduction reaction. CNFs should find a promising application field in fuel cell technology, due to their electrical and structural properties. CNFs were plated with platinum particles by an electroless plating method. CNF-based electrodes were produced by a sedimentation method. Polarization curves were measured in half cell tests, and physical characterization was carried out by scanning electron microscopy. It was shown that the fibers are capable of providing the required porosity with low binder content and an excellent electrical conductivity, as well as a good performance with low catalyst loading. The fibers allowed a reduction of the binder content in the electrode to prevent covering of catalyst with binder. With an optimization of the thickness of the electrode, the catalyst is lowered by 40 % without a significant loss of performance.