posted on 2020-03-24, 12:33authored byJia Chen, Mingming Guan, Kai Li, Shaokun Tang
Here
we report a new hybrid anion exchange membrane with enhanced
hydroxide conductivity and excellent chemical and dimensional stability
by incorporating quaternary ammonium (QA)-functionalized covalent
organic framework into brominated poly(2,6-dimethyl-1,4-phenylene
oxide) (BPPO). N,N,N′,N′ -Tetramethyl-1,6-hexanediamine
(TMHDA) was impregnated into the pores of COF-LZU1 via a vacuum-assisted
method, followed by reacting with allyl bromide. The generated QA
groups were immobilized within the highly ordered pores of COF-LZU1
via in situ polymerization, forming long-range ordered multiple ion
channels. The obtained QA@COF-LZU1 was then mixed with QAPPO to construct
a hybrid anion exchange membrane for anion exchange membrane fuel
cells (AEMFCs). The hydroxide conductivity of QA@COF-LZU1/PPO hybrid
membrane increased up to 168.00 mS cm–1 at 80 °C,
about 77% higher than that of pristine membrane. In addition, alkaline
stability and thermal stability of the hybrid membranes were obviously
enhanced. The excellent performance and the outstanding chemical stability
render the COF hybrid membrane a good candidate for the application
in AEMFCs.