On the role of the silica-containing catalyst layer for proton exchange membrane fuel cells

Abstract

The performance of a PEMFC (proton exchange membrane fuel cell) severely decreases as the relative humidity decreases. Herein, we present size-controlled SiO2 (silica) nanoparticles in the CLs (catalyst layers) to provide sufficient water to the Nafion ionomer. It is found that the microstructure of the agglomerated CL is notably improved using the SiO2 particles with smaller diameter. In addition, as the SiO2 particle diameter decreases, both the electrochemical surface area and ohmic performance are improved, as well as the wettability, for the PE