Highly Permeable Bucky Paper for the Gas Diffusion Layer of Fuel Cell Prepared by a Whole‐Process Solid Template Method

Abstract

Due to the control of porosity and pore size on mass transfer, the structure of the gas diffusion layer (GDL) has a critical impact on the performance of fuel cells. The bucky paper has high conductivity and abundant pores, which has potential to be used as GDL in fuel cells. Herein, a whole‐process solid template method is used to prepare the bucky paper with microcrystalline cellulose (MCC), whose porosity and pore size can be regulated quantitatively. The bucky paper with MCC as a pore‐forming agent has more larger pores, and these pores are mostly connected, which meet the needs of fuel cell application. The result of gas flux shows that the permeability of the bucky paper increases from the initial 12 to 240 mL min−1 kPa−1 cm−2 with MCC. The pore structure of bucky paper are significantly improved, so that the bucky paper with MCC leads to a higher fuel cell power density. Furthermore, the impedance result presents that with the addition of MCC, the mass transfer resistance of the fuel cells decreases significantly. It is fully supported in these results that MCC can modify the pores of the bucky paper and applied in proton exchange membrane fuel cells well.