Nanocomposite polymer electrolyte membrane for high performance microbial fuel cell: Synthesis, characterization and application

Abstract

In this work, nanocomposite membranes composed of poly (vinylidenefluoride-co-hexafluoropropylene) (PVDF-HFP)/Nafion/TiO2 are fabricated and evaluated for potential application as polymer electrolyte membrane (PEM) in microbial fuel cell (MFC). In particular, PVDF-HFP is partially sulfonated by treating the polymer (in granular form) with chlorosulfonic acid for a period of 7 h at 60°C. Further, TiO2 nanoparticles have been incorporated within the blend of Nafion and partially sulfonated PVDF-HFP. The fabricated nanocomposite membranes have been tested and utilized as a PEM in MFC for the evaluation of their electrical potency. The characteristic metal oxide bands obtained in FTIR spectra confirmed successful incorporation of TiO2 within the structure of polymer blend. XRD spectra suggested the semi-crystalline nature of the composite membrane. At a threshold content of TiO2 (7 wt%, T-7), water uptake of composite membrane has increased up to 27.7%, with an enhanced proton conductivity value (34.7 mS/cm) in comparison to that of Nafion-117 membrane (30.2 mS/cm). The anti-bio fouling effect is analyzed by SEM images. Nevertheless, T-7 membrane exhibited superior properties (like improved water uptake, proton conductivity, ion exchange capacity), and a significantly enhanced MFC performance like maximum current density (1926 ± 89 mA/m2), maximum power density (552.12 ± 26 mW/m2) as well as maximum COD removal (88.97%) amongst all the fabricated composite, as well as corresponding Nafion-117, membranes. © 2019 The Electrochemical Society.