A series of cation exchange membranes (CEMs) with different ion exchange capacitiy (IEC) values based on side-chain type partially fluorinated sulfonated poly(aryl ether)s (sSPFAEs) are prepared through aromatic nucleophilic substitution and solution casting

and subsequently used as the separator in microbial fuel cell (MFC).Their power production performances in double chamber MFCs are investigated and compared with commercial CEM.The obtained sSPFAE membranes have IEC of 0.97~1.56 mmol/g with thickness around 80 m

show water uptakes of about 20.9%~41.7%

and proton conductivities of 27.3~60.5 mS/cm

which are higher than those for commercial CEM with thickness of 420 m (22 mS/cm).For the MFCs with sSPFAE membranes

the intermal resistances are in the range of 29~64 according to the peak power density and the slope method from the polarization curves

and increase with the IEC; their columbic efficiencies are about 47.7%~55%.The membrane of sSPFAE-1.56 exhibits the maximum power output of 657.3 mW/cm2 and all the sSPFAE membranes outperform commercial CEM.According to the EIS analysis results for the whole MFC system by equivalent circuit simulation

the anodic diffusion resistances hold 87%~90% of the total resistances.Combining the CV analysis and EIS analysis with the electrode potential test results

the separating membranes have considerable influence upon the mass tranfer across the chambers as well as the anodic diffusion resistance.