Synergistic effect of aluminium phosphate and tungstophosphoric acid on the physicochemical properties of sulfonated poly ether ether ketone nanocomposite membrane

This study explores the synergistic effect of aluminium phosphate (ALP) nanoparticles and tungstophosphoric acid (TPA) on the physicochemical properties of sulfonated poly ether ether ketone (SPEEK) nanocomposite membranes. SPEEK/TPA/ALP nanocomposite containing optimum TPA (10 wt %) and varying ALP content (3–10 wt %) are fabricated to investigate the effect of ALP nanoparticles on membrane properties. Experimental results reveal that nanocomposite membrane containing 3 wt % ALP nanoparticles and 10 wt % TPA exhibits 3.3 and 18.8 times higher proton conductivity compared to 10 wt % TPA filled SPEEK composite membrane and reference SPEEK membrane. ALP nanoparticles help in retaining water within the membranes and thus 59.4% reduction in water desorption rate is achieved compared to SPEEK/TPA membrane. The leaching of TPA is reduced by 34.5% which helps in retaining membrane properties. Membranes are thermally stable up to 200°C. Microstructure of the composite films is investigated by scanning electron microscope.