Novel polyolefin/silicon dioxide/H3PO4 composite membranes with spatially heterogeneous structure for phosphoric acid fuel cell

► Novel polyolefin/SiO2/H3PO4 composite membranes for high temperature FC. ► The obtained membranes are a promising alternative to PBI-type. ► The composite membranes possess stable spatially heterogeneous structure. ► 0.5 V at 0.4 A/cm2 at 140 °C was achieved with hydrogen and air as reactants.