Gas Diffusion Layer

For a fuel cell, the Gas Diffusion Layer (GDL) may be fabricated with either carbon cloth or carbon paper. These are porous materials which allow gases to pass through to the catalyst layer. Since carbon is conductive, it facilitates the transport of electrons. Both the carbon paper and carbon cloth are available in either untreated or pretreated form. The treated form becomes hydrophobic and prevents the GDLs from becoming saturated by liquid water, while still allowing reactant gas and water vapor to pass through the pores of the material. The normal loading for treated material is 30% Teflon™.