Enhanced Performance of Sulfonated GO in SPEEK Proton-Exchange Membrane for Microbial Fuel-Cell Application

Sulfonated graphene oxide (SGO) was prepared using sulfuric acid and used as a nanofiller at various concentrations in self-fabricated sulfonated polyetheretherketone (SPEEK) to produce nanocomposite proton-exchange membranes for microbial fuel-cell (MFC) applications. The proton conductivity, water uptake, ion-exchange capacity (IEC), and MFC performance of the nanocomposite membranes (SPEEK-SGO) were compared with those of pristine SPEEK and SPEEK-graphene oxide (GO). The addition of sulfonated GO (2% by weight) in a SPEEK membrane enhanced the proton conductivity and showed the maximum power density of 1,028 +/- 7 mW center dot m-2 compared with SPEEK (570 +/- 4 mW center dot m-2) and SPEEK-GO (704 +/- 6 mW center dot m-2) membranes in a single-chamber MFC. The SPEEK-SGO 2% membrane exhibited a onefold greater performance than the Nafion 115 (sulfonated tetrafluoroethylene) membranes (512 +/- 6 mW center dot m-2) in the same MFC arrangement. The enhanced result of the SGO membranes was attributed to the presence of a high-density of sulfonic acid SO3H, OH, and COOH on SGO, which facilitates higher water uptake, proton conductivity, and IEC of the membrane. (c) 2020 American Society of Civil Engineers.

Automated summary

The addition of sulfonated graphene oxide to sulfonated polyetheretherketone membranes can significantly enhance proton conductivity and improve the performance of microbial fuel cells. The membrane with 2% sulfonated graphene oxide showed better performance compared to pristine polyetheretherketone and graphene oxide membranes.