Upgrading the electrochemical performance of graphene oxide-blended sulfonated polyetheretherketone composite polymer electrolyte membrane for microbial fuel cell application

In the present study, composite polymer electrolyte membranes were synthesized by the incorporation of graphene oxide (GO) in sulfonated polyetheretherketone (SPEEK) for simultaneous wastewater treatment and electricity generation. A variety of techniques were applied to characterize the chemical, crystal and morphological structure of the as-synthesized membranes. In addition, the water uptake, mass transfer, and oxygen diffusion coefficients, proton conductivity, ion exchange capacity, internal resistance, power density, coulombic efficiency and COD removal of the MFC system applied with SPEEK, SPEEK/GO composite membranes were studied and compared with the commercial Nafion117. The incorporation of various GO contents caused a decrease in oxygen diffusion and mass transfer coefficients of 7.45 × 10-6 cm2 s-1 and 0.00048 cm s-1, respectively. This was also shown that the SPEEK/GO3 membrane with proton conductivity 2.88 mS cm-1, power density 53.12 mW m−2, voltage 883 mV, and CE 3.74% showed higher performance compared to Nafion 117 membrane as a separator in MFC. Furthermore, the MFC with SPEEK/GO3 membrane gave slightly higher COD removal (88.7%) than that of MFC incorporating the Nafion 117 membrane (81.9%). The ion exchange capacity (IEC) and WU of as-prepared membranes were found to vary from 1 to 2.21 meq g-1 and from 44.31 to 67.85%, respectively. The results obtained were revealed that the MFC assembled SPEEK/GO3 composite membrane is demonstrated significant improvement in cell performance compared with commercial Nafion 117 membrane that qualifies it to be a promising candidate as a proton exchange membrane in the lab-scale microbial fuel cells. [Display omitted] •A series of SPEEK composite membrane with various GO loading was synthesized.•MFC performance of SPEEK and SPEEK/GO polymer electrolyte membrane was investigated.•Incorporation of nanosheet GO into the SPEEK membrane increases the MFC efficiency.•The weight ratio of GO3% with the composite membrane exhibited maximum COD removal.