Incorporation of silver graphene oxide and graphene oxide nanoparticles in sulfonated polyether ether ketone membrane for power generation in microbial fuel cell

Abstract

This study aims to design a new membrane for Microbial Fuel Cell (MFC) applications, where the membrane should have good proton conductivity, low oxygen permeability and anti-biofouling properties. The self-fabricated composite membranes are Graphene Oxide/Sulfonated Polyether Ether Ketone (GO-SPEEK) and Silver Graphene Oxide/Graphene Oxide/Sulfonated Polyether Ether Ketone (AgGO-GO-SPEEK). The proton conductivity of AgGO-GO-SPEEK membrane is 54.2% higher and the oxygen diffusion coefficient is 76.7% lower than Nafion® 117 membrane, yielding higher selectivity as separator in MFC applications. At the earlier optimum stage, MFC with GO-SPEEK generates the highest maximum power density (1134 mW m−2). Voltage achieved for first three feed cycles after enrichment are 620 mV–650 mV for all MFC system. However, the highest maximum power density (896 mW m−3) is attained by MFC with AgGO-GO-SPEEK membrane after 100 days of operation. The Electrochemical Impedance Spectroscopy (EIS) results show that AgGO-GO-SPEEK membrane has the lowest increment in terms of the membrane's resistance. AgGO-GO-SPEEK,a better anti-biofouling property membrane, leads to a longer and stable power production, caused by the better ion transport through membrane. The results indicated that AgGO-GO-SPEEK membrane is a promising alternative membrane to replace Nafion® 117 as a separator in the MFC.