Abstract
In this paper, a new functional diamine monomer 2-methyl-1,4-bis(4-amino-2-trifluoromethyl) benzene (FAPOB) is designed and synthesized for further improving the performance of branched sulfonated polyimide (SPI–B) membrane for implementation in vanadium redox flow battery (VRB). At the same time, the sulfonation levels of SPI-B membranes are accurately regulated by modifying the proportion of FAPOB and 4,4′-diaminobiphenyl-2,2′-disulphonic acid. Among them, the SPI-B-50 membrane with 50 % sulfonation degree exhibits a remarkable proton selectivity of 2.31 × 105 S min/cm3, which is 5.5 times higher than the Nafion 212 (NR212) membrane. Moreover, the SPI-B membrane's stability is significantly improved due to its branched structure and the presence of numerous trifluoromethyl groups. Compared to NR212 membrane, SPI-B-50 membrane demonstrates superior coulomb and energy efficiencies at the same current density. Furthermore, the SPI-B-50 membrane exhibits a higher voltage holding capacity compared to the NR212 membrane. Remarkably, the SPI-B-50 membrane maintains stable efficiencies even after undergoing more than 500 charge-discharge cycles. This research not only involves the innovative synthesis of a novel diamine monomer but also the construction of various SPI-B membranes with a unique molecular structure specifically designed for VRB applications.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
