Sulphonated graphene oxide as functionalized filler for polymer electrolyte membrane with enhanced anti-biofouling in microbial fuel cells

This research focuses on the development of a polymer electrolyte membrane (PEM) which is intended to increase power generation while addressing the persistent issue of biofouling in microbial fuel cells (MFC). The central hypothesis of this research work is that a novel PEM made from sulphonated polyether ether ketone (SPEEK) grafted with styrene sulphonic acid (SSA) integrated with sulphonated graphene oxide (SGO) will improve the membrane properties as well as enhance the anti-biofouling effect. The optimal percentage of SSA grafting has been determined based on physicochemical properties of the membrane. Various weight percentages of SGO (2.5, 5, 7.5, & 10 wt%) were introduced to the SPEEK/SSA base polymer to augment the physicochemical properties and also to defend against biofouling. Among the tested membranes, the SPEEK/SSA+5 % SGO composite membrane demonstrates the highest water uptake (106.2 +/- 1.9 %) and ion exchange capacity (1.55 +/- 0.2 meq g(-1)). Due to these superior properties, it achieves the maximum power density of 203 mW m(-2) and an open circuit voltage (OCV) surpassing 700 mV. The crystal violet assay performed post-MFC operation affirms that the nanocomposite membrane effectively inhibits bacterial fouling. This study positions itself as a solution for long-term, high-performance MFC operations, all while significantly increasing power output and reducing biofouling concerns.