Abstract: Metal organic framework (MOF) materials have attracted widespread attention due to their tunable structure, high porosity, and large specific surface area. MOF modified with functional groups were introduced into ionic polymers that could provide proton conduction, which could prepare proton exchange membranes with high proton conductivity. In this paper, UiO-66-NH₂ were introduced into sulfonated polyphosphazene (SPFPP) to prepare composite proton exchange membranes, the thermal stability, swelling degree, water uptake, and proton conductivity were characterized. Composite membranes exhibits excellent thermal stability, the swelling degree of the composite membranes are lower than that of the pure SPFPP membrane. UiO-66-NH₂ could improve the water retention capacity of composite membranes, resulting in higher water uptakes of composite membranes than pure SPFPP membranes. This higher water retention capacity could improve the proton conductivity of the membrane under high humidity conditions. The proton conductivity of composite membranes SP/UiO-66-NH₂-0.6 reaches up to 0.179 S/cm under 80 ℃, 100%RH, while the proton conductivity of pure SPFPP membranes is 0.120 S/cm under the same conditions.

Key words: metal organic framework material, UiO-66-NH₂, sulfonated polyphosphazene, swelling degree, water uptake, proton conductivity