3.2.3. Optimization of the Nafion ionomer contents of
cathodes
The role of an ionomer binder in the catalyst layer is to confer
proton conductivity, which is one of the mandatory structural
requirements for high fuel cell performance. The ratio of
ionomer to catalyst is critical in determining the structural
properties of the cathode catalyst layer in terms of proton
conductivity and porosity. The pore structure of the cathode is
of immense importance as it controls the diffusion of the
reactant gas, air/oxygen, to the active sites and the removal of
product water. Generally, it is observed that when MEAs are
fabricated by decal transfer method, the resultant electrode