Effect of silver incorporated sulphonated poly ether ether ketone membranes on microbial fuel cell performance and microbial community analysis

The present study introduces silver (2.5, 5, 7.5 and 10 wt%) as an effective additive in Sulphonated Poly Ether Ether Ketone (SPEEK) membrane to reduce membrane biofouling in Microbial Fuel Cell (MFC) functioning when operated for three months. The incorporation of the inorganic filler into the polymer backbone is investigated by Scanning Electron Microscope (SEM), Energy Dispersive Spectroscopy (SEM-EDAX), Fourier Transform Infra-Red (FTIR) spectroscopy, X-Ray Diffraction (XRD) and Thermo Gravimetric Analysis (TGA) studies. The suitability of the prepared composites is evaluated through several membrane studies in comparison with widely investigated Nafion 117. MFC performance studies showed the highest maximum power density of 156 ? 0.5 mW m- 2 by making use of SPEEK + 7.5 wt% Ag membrane upon three months of tubular Microbial Fuel Cell (MFC) operation. The antibacterial activity of silver ions reduces biofilm formation. Microbial community analysis of the formed biofilm performed through 16S rRNA sequencing identified 33 types of phyla which contributed to the electron transfer. The present research not only provides an alternate composite membrane with reduced biofouling but also identifies the microbes that contributed effectively in bioelectrogenesis thereby providing insights for future studies on prolonged MFC operation.

Automated summary

This study introduced silver as an effective additive in SPEEK membrane to reduce membrane biofouling in MFC. The incorporation of silver ions reduced biofilm formation, leading to the highest maximum power density from SPEEK + 7.5% Ag membrane after three months of MFC operation. Microbial community analysis identified microbes contributing to electron transfer.