Escorihuela Jorge, García-Bernabé Abel, Montero Álvaro, Sahuquillo Óscar, Giménez Enrique, Compañ Vicente
Departamento de Termodinámica Aplicada, (ETSII) Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain.
Departament de Química Orgànica, Universitat de València, Av. Vicent Andrés Estellés s/n, 46100 Burjassot, Valencia, Spain.
Polymers (Basel). 2019 Apr 22;11(4):732. doi: 10.3390/polym11040732.
A series of proton exchange membranes based on polybenzimidazole (PBI) were prepared using the low cost ionic liquids (ILs) derived from 1-butyl-3-methylimidazolium (BMIM) bearing different anions as conductive fillers in the polymeric matrix with the aim of enhancing the proton conductivity of PBI membranes. The composite membranes prepared by casting method (containing 5 wt. % of IL) exhibited good thermal, dimensional, mechanical, and oxidative stability for fuel cell applications. The effects of anion, temperature on the proton conductivity of phosphoric acid-doped membranes were systematically investigated by electrochemical impedance spectroscopy. The PBI composite membranes containing 1-butyl-3-methylimidazolium-derived ionic liquids exhibited high proton conductivity of 0.098 S·cm at 120 °C when tetrafluoroborate anion was present in the polymeric matrix. This conductivity enhancement might be attributed to the formed hydrogen-bond networks between the IL molecules and the phosphoric acid molecules distributed along the polymeric matrix.
制备了一系列基于聚苯并咪唑（PBI）的质子交换膜，使用源自1-丁基-3-甲基咪唑鎓（BMIM）且带有不同阴离子的低成本离子液体（ILs）作为聚合物基质中的导电填料，目的是提高PBI膜的质子传导率。通过流延法制备的复合膜（含有5 wt.%的IL）在燃料电池应用中表现出良好的热稳定性、尺寸稳定性、机械稳定性和氧化稳定性。通过电化学阻抗谱系统研究了阴离子、温度对磷酸掺杂膜质子传导率的影响。当聚合物基质中存在四氟硼酸根阴离子时，含有1-丁基-3-甲基咪唑鎓衍生离子液体的PBI复合膜在120°C时表现出0.098 S·cm的高质子传导率。这种传导率的提高可能归因于IL分子与沿聚合物基质分布的磷酸分子之间形成的氢键网络。
