Hydrogen Bond and Dipole–Dipole Interaction Enabling Ultrastable, Quick Responding, and Self-Healing Proton Exchange Membranes for Fuel Cells
Shanyun Mo, Zihui Li, Junda Chen, Yue Chen, Ning Wang, Chunmei Tang, Ling Meng, Lei Du, Lixin Xing, Siyu Ye
Abstract
High Resolution Image Download MS PowerPoint Slide Proton exchange membranes (PEMs) are subject to mechanical degradation, such as microcracks and pinhole formation, under real-world fuel cell operating conditions, which leads to great issues in terms of device death and safety concerns. Therefore, PEMs with self-healing features are imperative but have rarely been used for proton exchange membrane fuel cells (PEMFCs). Here, a dimensionally stable and self-healing PEM is developed by tuning the hydrogen bond and dipole–dipole interactions between the mature perfluorinated sulfonic acid (PFSA) and a self-healing copolymer, which is specifically synthesized with hexafluorobutyl acrylate (HFBA) and acrylic acid (AA). This hexafluorobutyl acrylate-acrylic acid copolymer (HFBA- co -AA) is suggested as the key to improving the self-healing efficiency of the blended PFSA/HFBA- co -AA membrane. This PFSA/HFBA- co -AA membrane can recover 43.6% of the original tensile strength within only 20 min at 80 °C. This study may pave an avenue toward the development of reliable and durable PEM for fuel cells.