Nanosulfonated silica incorporated SPEEK/SPVdF-HFP polymer blend membrane for PEM fuel cell application

Abstract

Sulfonated silica particles are admixed with sulfonated poly (ether ether ketone) (SPEEK)/sulfonated poly (vinylidene fluoride-co-hexafluoropropylene) (SPVdF-HFP), with various ratios by means of solvent casting. X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), atomic force microscopy (AFM), and energy-dispersive X-ray spectroscopy (EDAX) were employed for characterizing the polymer electrolytes. Physicochemical and electrochemical characterizations such as ion exchange capacity, water uptake, swelling ratio, lambda values, temperature-dependent proton conductivity, and performance for prepared polymer composites are also analyzed. From the XRD and FTIR confirms the phase analysis and complex formation of the prepared polymer electrolytes. For 6 wt% S-SiO2, incorporated polymer membrane shows the high water uptake (36.5%), swelling ratio (15.9%), and ion exchange capacity (1.70 meq g−1) values compared to the respective samples. The highest proton conductivity value obtained for the 6 wt% S-SiO2 incorporated polymer membrane of 80 wt% SPEEK-20 wt% SPVdF-HFP is 7.9 × 10−2 S cm−1. The current density and power density value of 354 mA cm−2 and 110 mW cm−2 with an OCV of 0.95 V at 90 °C under the 100% RH.