Abstract:
The main obstacle of wide commercialization of proton exchange membrane is to maintain the high conductivity and low swelling ratio of proton exchange membrane at higher temperature under fully hydrated state. In order to solve this issue, by using poly-dopamine (PDA) as an intermediate layer, ZrO
2 was formed on the commercial sulfonated polysulfone (PSF) porous membrane matrix, a facial approach of preparing well performed composite proton exchange membrane was proposed. The influence of PDA deposition conditions and ZrO
2 mineralization process on the surface morphology and element distribution of PSF-PDA-ZrO
2 composite membrane were investigated. The PSF-PDA modified membrane with PDA deposition time of 5 h was selected for mineralization. It is found that the content of Zr element on the surface mineralized layer of PSF-PDA-ZrO
2 composite membranes is significantly increased with increasing mineralization time. The water uptake, swelling ratio and proton conductivity of PSF-PDA-ZrO
2 composite membrane were tested. The results show that the surface of ZrO
2 mineralized layer significantly inhibits the swelling ratio of PSF-PDA-ZrO
2 composite membranes at higher temperature compared with PSF porous membranes, and the swelling ratio of composite membranes gradually reduces with the increase of ZrO
2 mineralization time. The proton conductivity of PSF-PDA-ZrO
2 composite membranes with mineralization time for 1 h, 5 h, 12 h and 24 h is higher than that of the pure PSF porous membrane, and the conductivity of the PSF-PDA-ZrO
2 composite membranes decreases gradually with the increase of mineralization time. The proton conductivity of PSF-PDA-ZrO
2 composite membrane after PDA deposition for 5 h and mineralization for 1 h is up to 0.117 Scm
-1 at 90℃, which is 2.5 times of the PSF porous basement membrane.