Effect of the Microporous Layer Structure and Hydrophobicity on the Performance of Direct Methanol Fuel Cells

Abstract

Direct methanol fuel cells (DMFCs) have drawn special attention for their portability and fewer safety concerns because of the use of liquid fuels. The microporous layers (MPLs) play an important role in improving the performance of DMFCs, especially at high current density. In this work, polypyrrole nanowire networks grown on carbon paper by in-situ electrochemical polymerization are used as cathode MPL. The hydrophobicity of the MPL is tuned by changing the amount of polytetrafluoroethylene (PTFE). With the optimized structure and hydrophobicity of the MPL, the peak power density of the DMFC is 102 m W cm-2, which is 24% higher than that of the DMFC with traditional MPL consisted of carbon black.