He Xueyi, Gang Mingyue, Li Zhen, He Guangwei, Yin Yongheng, Cao Li, Zhang Bei, Wu Hong, Jiang Zhongyi
Key Laboratory for Green Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China.
Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China.
Sci Bull (Beijing). 2017 Feb 28;62(4):266-276. doi: 10.1016/j.scib.2017.01.022. Epub 2017 Jan 19.
With well-defined channels and tunable functionality, metal-organic frameworks (MOFs) have inspired the design of a new class of ion-conductive compounds. In contrast to the extensive studies on proton-conductive MOFs and related membranes attractive for fuel cells, rare reports focus on MOFs in preparation of anion exchange membranes. In this study, chloromethylated MIL-101(Cr) was prepared and incorporated into chloromethylated poly (ether ether ketone) (PEEK) as a multifunctional filler to prepare imidazolium PEEK/imidazolium MIL-101(Cr) (ImPEEK/ImMIL-101(Cr)) anion exchange membrane after synchronous quaternization. The successful synthesis and chloromethylation of MIL-101(Cr) were verified by transmission electron microscopy, X-ray diffraction and Fourier transform infrared spectroscopy while the enhanced performance of composite membranes in hydroxide conductivity, mechanical strength and dimensional stability were evaluated by alternating-current impedance, electronic stretching machine and measurement of swelling ratio. Specifically, incorporating 5.0wt% ImMIL-101(Cr) afforded a 71.4% increase in hydroxide conductivity at 20°C, 100% RH. Besides, the composite membranes exhibited enhanced dimensional stability and mechanical strength due to the rigid framework of ImMIL-101(Cr). At room temperature and the ImMIL-101(Cr) content of 10wt%, the swelling ratio of the ImPEEK/ImMIL-101(Cr) was 70.04% lower while the tensile strength was 47.5% higher than that of the pure membrane.
金属有机框架材料（MOFs）具有明确的通道和可调的功能，激发了新型离子导电化合物的设计灵感。与对燃料电池有吸引力的质子导电MOFs及相关膜的广泛研究相比，关于MOFs用于制备阴离子交换膜的报道很少。在本研究中，制备了氯甲基化的MIL-101(Cr)，并将其作为多功能填料掺入氯甲基化的聚醚醚酮（PEEK）中，经同步季铵化后制备咪唑鎓PEEK/咪唑鎓MIL-101(Cr)（ImPEEK/ImMIL-101(Cr)）阴离子交换膜。通过透射电子显微镜、X射线衍射和傅里叶变换红外光谱验证了MIL-101(Cr)的成功合成和氯甲基化，同时通过交流阻抗、电子拉伸机和溶胀率测量评估了复合膜在氢氧化物传导率、机械强度和尺寸稳定性方面的增强性能。具体而言，在20°C、100%相对湿度下，掺入5.0wt%的ImMIL-101(Cr)使氢氧化物传导率提高了71.4%。此外，由于ImMIL-101(Cr)的刚性框架，复合膜表现出增强的尺寸稳定性和机械强度。在室温下且ImMIL-101(Cr)含量为10wt%时，ImPEEK/ImMIL-101(Cr)的溶胀率比纯膜低70.04%，而拉伸强度比纯膜高47.5%。
