Conductive superhydrophobic coating on gas diffusion layer for enhanced proton exchange membrane fuel cell performance

초록

The Gas Diffusion Layer (GDL) is a crucial component of the Proton Exchange Membrane Fuel Cell (PEMFC). It plays several vital roles, including the transport of the reaction gases?hydrogen and oxygen?the removal of water produced during electrochemical reaction, and the transfer of electrons. Typically, GDLs consist of two main layers: a Gas Diffusion Backing layer (GDB) that provides structural support, and a Microporous Layer (MPL) that helps retain the catalyst and enhances contact resistance between the catalyst and the GDL. Most commercial GDBs are made from porous carbon paper or carbon cloth. To prevent the accumulation of water generated by electrochemical reactions and to facilitate its drainage, a hydrophobic coating is often applied using fluoropolymers, primarily polytetrafluoroethylene (PTFE). However, many fluoropolymer coatings are insulating, leading to a decrease in the electrical conductivity of the GDB, which subsequently reduces the overall electrical conductivity of the GDL.