Study on the medium-low-humidity performance of MTES for gas diffusion layer in PEMFC

Trimethylethoxysilane (MTES) as a hydrophobic material, graphene as a conductive material, and electrospinning as a preparation method are used to successfully prepare MTES and graphene conductive-hydrophobic composite fiber membranes. A control group was prepared based on the different doping qualities of graphene. Also, the composite fiber membrane as a microporous layer is used for a proton exchange membrane fuel cell. Polarization curve test results show that with the increase of graphene, the voltage loss of the composite fiber membrane gradually decreases, and fuel cell performance is significantly better than that of commercial GDL29BC. Electrochemical impedance spectroscopy test results show that the material transfer impedance of the composite fiber membrane is lower than that of GDL29BC. It also showed that the power density difference of the composite fiber membrane was low when the humidity was 40% and 60%, indicating that the composite fiber membrane has a good self-humidifying effect.