Effect of PTFE Content and Sintering Temperature on the Properties of a Fuel Cell Electrode Backing Layer

The effects of the polytetrafluoroethylene (PTFE) content and sintering temperature on the properties of a fuel cell electrode backing layer are studied in this work. Characterization of the electrical conductivity, hydrophobicity, and surface structure of the backing layer is carried out for various PTFE content values (15–45 wt. %) and sintering temperatures (175–400 °C). The results showed that, generally, the electrical conductivity of the backing layer surface decreased whereas the hydrophobicity increased as the PTFE content and the sintering temperature increased. Based on the observations made via scanning electron microscope (SEM) analysis and testing of the electrical conductivity and hydrophobicity, the PTFE content should not exceed 35 wt. %, and the best sintering temperature was 350 °C.