Preparation And Properties Of Sulfonated Polyaryl Ether Ketone Sulfone/Heteropoly Acid Organic/Inorganic Composite Membrane Containing Carboxyl Groups

The proton exchange membrane fuel cell?PEMFC?is a new type of clean and efficient electrochemical device,which has the advantages of high energy conversion rate,safety and reliability,good compoundability and good portability.Proton exchange membrane?PEMs?is a key component of proton exchange membrane fuel cell.It not only has the function of blocking electrons,but also plays a key role in conducting protons.Currently,the commercial Nafion membrane produced by Du Pont is a solid polymer electrolyte with a perfluorinated structure.It has great chemical and thermal stability,high electrical conductivity and excellent mechanical properties.However,the poor alcohol resistance of Nafion membranes,the low proton conductivity under high-temperature,and its high manufacturing cost and complicated preparation techniques have hindered its widespread application.In order to improve the performance of the membrane and the shortage of commercial Nafion membrane materials,it is urgent to develop new membrane materials.Currently,sulfonated aromatic polymers?SPAEKS?are PEMs with the highest potential due to their excellent chemical and thermal stability and good mechanical strength.SPAEKS membrane materials mainly rely on sulfonic acid groups to conduct protons.With the increase of sulfonation degree of the membranes,SPAEKS membranes are prone to over swelling,which will lead to a significant decline in the mechanical properties,oxidation stability,dimensional stability and alcohol resistance of the membranes,so it will directly lead to the decline in the performance of these SPAEKS membranes.Therefore,it is very important to obtain the excellent performance of SPAEKS proton exchange membrane materials by chemical or physical modification.In this paper,the self-assembly method is used to prepare the proton conducting heteropoly acid?POM?materials{[Co?H2O?₈][H?H₂O?_2.5]?HINO?4(PMo₁₂O₄₀)}n.The half-occupied oxygen sites of water molecules in[Co?H2O?₈]²⁺and H⁺?H₂O?_2.5clusters are beneficial to form hydrogen-bond network.And then hydrogen-bond network could provide transmission sites for protons,thus facilitates proton transport.Then,SPAEKS polymer was synthesized by polycondensation,and a series of C-SPAEKS hybrid films were prepared by blending with POM filler.The experimental results show that POM heteropoly acid is homogeneously dispersed in SPAEKS at low content of POM.The composite film has good mechanical properties,excellent folding properties and long-term stability.Even at 80?,the swelling rate of hybrid membrane is very low?less than 13%?.In addition,C-SPAEKS P15%showed high proton conductivity(0.048 s cm^-1at 30?,0.099 s cm^-1at 90?)and low methanol permeability(5.02×10^-7cm²s^-1).Compared with pure C-SPAEKS,the overall performance of POM based hybrid films is improved.It is proved that the series of POM based organic-inorganic complexes have a good application potential in the field of proton exchange membrane.