A facile approach of fabricating proton exchange membranes by incorporating polydopamine-functionalized carbon nanotubes into chitosan

Recently, fabricating low-cost and high-performance proton exchange membranes (PEMs) with carbon nanotubes (CNTs) and chitosan (CS) have been extensively studied. Herein, we reported a facile but effective method to prepare CS-based PEM with polydopamine (PDA) functionalized CNTs ([email protected]). The CS/[email protected] composite membranes were prepared by incorporating [email protected] into CS matrix followed by ion cross-linking with sulfuric acid. Due to the hydrogen bonding between the CS matrix and PDA coating, the thermal, mechanical and oxidation stability of the CS/[email protected] composite membranes were improved. Moreover, the proton conductivity was also improved owing to the improved dispersion of [email protected] in the CS matrix and the electrostatic interaction between [email protected] and CS matrix. The maximum proton conductivity can reach to as high as 0.028 S cm−1 under 80 °C with 2 wt% loading of [email protected] These results indicate that the CS/[email protected] composite membranes have great potential to be used as PEMs in fuel cells.