Morphology Changes in Perfluorosulfonated Ionomer from Thickness and Thermal Treatment Conditions
2020; American Chemical Society; Volume: 36; Issue: 14 Linguagem: Inglês
10.1021/acs.langmuir.9b03564
ISSN1520-5827
AutoresXiao Gao, Kentaro Yamamoto, Tomoyasu Hirai, Tomoki Uchiyama, Noboru Ohta, Naoki Takao, Masashi Matsumoto, Hideto Imai, Seiho Sugawara, Kazuhiko Shinohara, Yoshiharu Uchimoto,
Tópico(s)Advancements in Solid Oxide Fuel Cells
ResumoThe morphological changes of Nafion thin films with thicknesses from 10 to 200 nm on Pt substrate with various annealing histories (unannealed to 240 °C) were systematically investigated using grazing incidence small-angle X-ray scattering (GISAXS) and grazing incidence wide-angle X-ray scattering (GIWAXS). The results revealed that the hydrophilic ionic domain and hydrophobic backbone in Nafion thin films changed significantly when the annealing treatment exceeded the cluster transition temperature, which decreased proton conductivity, due to the constrained hydrophilic/hydrophobic phase separation, and increased the crystalline-rich domain. This research contributed to the understanding of ionomer thermal stability in the catalyst layer, which is subjected to thermal annealing during the hot-pressing process.
Referência(s)