Preparation and characterization of carbon black/pitch-based carbon fiber paper composites for gas diffusion layers

We prepared carbon Ketjenblack (KB)/carbon fiber papers (CFPs) from pitch-based carbon fibers (CFs) by web laid processing, and the electrical conductivity and mechanical properties of the CFPs were investigated according to the structure and morphology of the CFs by the addition of KB as a conductive filler at different carbonization temperatures. The wet-laid processing fabrication method for CFPs consisted of four steps: dispersion of CFs, preparation of a CF web, impregnation of phenol resin, and heat treatment. The results showed that the electrical resistance and tensile strength of the CFPs were low at high-heat-treatment temperatures. Notably, CFPs with a thickness of 190 mu m, porosities of 86.7%, and specific resistance of 7.795 x 10(-2) Omega cm were obtained by after adding 6 wt.% of KB at a carbonization temperature of 800 degrees C.