Nanocomposite membrane and microbial community analysis for improved performance in microbial fuel cell

Abstract

To improve the performance of a microbial fuel cell (MFC), four variations of sulphonated silicon dioxide (S-SiO2) was incorporated into sulphonated poly ether ether ketone (SPEEK) membranes. S-SiO2 was characterized by scanning electron microscopy (SEM), fourier transform infra-red spectroscopy (FTIR) and X-ray diffraction (XRD) to confirm morphological, physical and chemical characteristics. The prepared membranes were incorporated into a fabricated tubular MFC of 300 mL holding capacity. Membrane characterizations such as water uptake, ion exchange capacity (IEC) and proton conductivity were determined. The highest maximum output of 154 ± 1.5 mW m−2 is produced by SPEEK +7.5 wt% S-SiO2 with an IEC of 1.82 ± 0.08 meq g-1 and an oxygen mass transfer coefficient of 1.42 × 10−6 cm s-1. Microbial community studies show the prevalence of novel microbial strains with the predominance of 3 distinct phyla, namely Betaproteobacteria, Gammaproteobacteria and Firmicutes. The results suggest that the prepared nanocomposite membrane proves to be an efficient and sustainable alternative for improving the performance of a MFC without abating the essential membrane characteristics.