Poly(4-vinylpyridine) Based Semi-Interpenetrating Cross-Linked High Temperature Proton Exchange Membranes for Fuel Cells

Abstract

A series of high temperature polymer electrolyte membranes are fabricated using a commercially low-cost poly(4-vinylpyridine). Because of the existence of the amount of pyridine groups, poly(4-vinylpyridine) possesses a strong interaction with phosphoric acid molecules. In order to improve the dimensional and mechanical stability, the semi-interpenetrating network is constructed by employing poly(vinyl chloride) as the supporting material because of its good compatibility with poly(4-vinylpyridine) and poly(vinyl benzyl chloride) as the cross-linker due to the high nucleophilicity. The macromolecular cross-linked semi-interpenetrating membranes exhibit high conductivity and good mechanical properties simultaneously. Consequently, the optimized membrane (i.e., 10% CL-PP) with an acid doping content of 176% displays a good conductivity of 45.8 mS cm–1 at 160 °C and a high mechanical strength of 10.3 MPa at room temperature. The H2–O2 high temperature proton exchange membrane fuel cell based on the above-mentioned membrane achieves a peak power density of 478 mW cm–2 at 160 °C without any backpressure. This work provides a facile method on the preparation of high-performance semi-interpenetrating membranes for fuel cell applications.

Semi-Interpenetrating High-Temperature Proton Exchange Membranes Based on Cross-Linked Poly(fluorenyl-terphenyl-piperidinium) and Poly(vinylbenzyl chloride-co-vinylbenzyl chloride) for Fuel Cells

“…The PA uptakes of PFTP/PSVIm-VBC-20%, PFTP/PSVIm-VBC-30%, and PFTP/PSVIm-VBC-40% membranes were 137.2, 160.3, and 171.7%, respectively, which were higher than that of cPFTP (124.6%) because the introduction of imidazolium groups offered extra alkaline active sites for PA absorption. , The LS and AS of the cPFTP membrane were 8.3 and 15.8%, respectively, whereas the values for the PFTP/PSVIm-VBC-40% membrane were 17.3 and 34.2%, respectively. Although the swelling ratio of the PFTP/PSVIm-VBC- x % membrane increased with increasing PA uptake, it is lower than that of membranes with a similar structure. , …”

“…In addition, CO at the parts per million level results in platinum catalyst poisoning; therefore, extremely high-purity H 2 is required for PEMFCs, which greatly increases the cost of PEMFC use. The operation of PEMFCs at high temperatures has many advantages, such as improved CO tolerance of anodic platinum catalysts, enhanced reaction kinetics at both electrodes, and simplified heat and water management. − Therefore, the development of high-temperature PEMs (HT-PEMs) is urgently required for the application of PEMFCs.…”