Abstrakt: |
The composite electrolyte membranes were fabricated using sulfonated polyether ether ketone (SPEEK) as the precursor material and supercritical carbon dioxide extraction technology, resulting in enhanced ionic conductivity, water absorption, and low methanol permeability. The water absorption of polyether ether ketone (PEEK) electrolyte membranes was enhanced by the sulfonation process, attributed to the formation of efficient ion pathways. The results showed that the ion exchange capacity(IEC) value of the SPEEK electrolyte membrane increased to 1.38 meq/g as the sulfonation time was extended from 3 h to 12 h, concurrently resulting in an increase in the degree of sulfonation to 46%. After sulfonation, the decomposition temperature of the electrolyte membrane decreased, reaching a lower value of 420 °C. As the sulfonation time increased, the ionic conductivity exhibited an increase from 1.37 x 10-10 S/cm to 1.16 x 10-4 S/cm, meanwhile the methanol diffusion coefficient demonstrated a decrease to 2.183 x 10-7 cm²/s. The study indicates that using sulfonation and supercritical carbon dioxide fluid extraction processes can prepare SPEEK electrolyte membrane with high ionic conductivity and low methanol permeability. [ABSTRACT FROM AUTHOR] |