Jump to Main Content
Preparation and Characterization of Nonaqueous Proton-Conducting Membranes with Protic Ionic Liquids
- Lu, Fei, Gao, Xinpei, Yan, Xiaojun, Gao, Hejun, Shi, Lijuan, Jia, Han, Zheng, Liqiang
- ACS Applied Materials & Interfaces 2013 v.5 no.15 pp. 7626-7632
- X-radiation, asymmetric membranes, chlorides, dielectric spectroscopy, fuel cells, ionic liquids, phosphoric acid, scanning electron microscopy, thermal stability, thermogravimetry
- Hybrid Nafion membranes were successfully fabricated by incorporating with protic imidazolium ionic liquids 1-(2-aminoethyl)-3-methylimidazolium chloride ([MimAE]Cl), 1-(2-hydroxylethyl)-3-methylimidazolium chloride ([MimHE]Cl), and 1-carboxylmethyl-3-methylimidazolium chloride ([MimCM]Cl) for high-temperature fuel cells. The composite membranes were characterized by impedance spectroscopy, small-angle X-ray scattering (SAXS), scanning electronic microscopy (SEM), and thermogravimetric analysis (TGA). The incorporated protic ionic liquids enhance the doping of phosphoric acid (PA) and result in a relatively high ionic conductivity. The Nafion/10 wt % [MimAE]Cl/PA composite membrane exhibits an ionic conductivity of 6.0 mS/cm at 130 °C without humidification. [MimAE]Cl can swell the Nafion matrix more homogeneously than [MimHE]Cl or [MimCM]Cl, which results in a better ionic conductivity. It is notable that the composite Nafion/IL/PA membranes have a better thermal stability than the pristine Nafion membranes.