Department of Materials Science and Engineering, National Taiwan University of Science and Technology , Taipei 10617, Taiwan.
Material and Chemical Research Laboratories Division of Polymer Research, Industrial Technology Research Institute , Hsinchu 30011, Taiwan.
ACS Appl Mater Interfaces. 2017 Mar 22;9(11):9805-9814. doi: 10.1021/acsami.7b00919. Epub 2017 Mar 8.
Novel sulfonated poly(ether sulfone) copolymers (S4PH-x-PSs) based on a new aromatic diol containing four phenyl substituents at the 2, 2', 6, and 6' positions of 4,4'-diphenyl ether were synthesized. Sulfonation was found to occur exclusively on the 4 position of phenyl substituents by NMR spectroscopy. The ion exchange capacity (IEC) values can be controlled by adjusting the mole percent (x in S4PH-x-PS) of the new diol. The fully hydrated sulfonated poly(ether sulfone) copolymers had good proton conductivity in the range 0.004-0.110 S/cm at room temperature. The surface morphology of S4PH-x-PSs and Nafion 212 was investigated by atomic force microscopy (tapping-mode) and related to the percolation limit and proton conductivity. Single H/O fuel cell based on S4PH-40-PS loaded with 0.25 mg/cm catalyst (Pt/C) exhibited a peak power density of 462.6 mW/cm, which was close to that of Nafion 212 (533.5 mW/cm) at 80 °C with 80% RH. Furthermore, fuel cell performance of S4PH-35-PS with various relative humidity was investigated. It was confirmed from polarization curves that the fuel cell performance of S4PH-35-PS was not as high as that of Nafion 212 under fully hydrated state due to higher interfacial resistance between S4PH-35-PS and electrodes. While under low relative humidity (53% RH) at 80 °C, fuel cells based on S4PH-35-PS showed higher peak power density (234.9 mW/cm) than that (214.0 mW/cm) of Nafion 212.
基于 4,4'-二苯醚的新型含四个苯取代基的芳族二醇（2,2',6,6'位取代）合成了新型磺化聚醚砜共聚物（S4PH-x-PSs）。通过 NMR 光谱发现磺化仅发生在苯取代基的 4 位。通过调整新二醇的摩尔百分比（x 在 S4PH-x-PS 中）可以控制离子交换容量（IEC）值。完全水合的磺化聚醚砜共聚物在室温下具有 0.004-0.110 S/cm 的良好质子电导率。通过原子力显微镜（敲击模式）研究了 S4PH-x-PSs 和 Nafion 212 的表面形态，并与渗流极限和质子电导率相关联。基于负载 0.25 mg/cm 催化剂（Pt/C）的 S4PH-40-PS 的单 H/O 燃料电池在 80°C 和 80%RH 下表现出 462.6 mW/cm 的峰值功率密度，接近 Nafion 212（533.5 mW/cm）。此外，还研究了具有不同相对湿度的 S4PH-35-PS 燃料电池的性能。通过极化曲线证实，由于 S4PH-35-PS 与电极之间的界面电阻较高，在完全水合状态下，S4PH-35-PS 的燃料电池性能不如 Nafion 212 高。然而，在 80°C 下相对湿度较低（53%RH）时，基于 S4PH-35-PS 的燃料电池显示出比 Nafion 212（214.0 mW/cm）更高的峰值功率密度（234.9 mW/cm）。
