Preparation And Properties Of Composite Sulfonated Poly(Arylene Ether)s/ Graphene Oxide Proton Exchange Membrane

As a kind of energy conversion device, fuel cell(FC) is getting more and more attention. Proton exchange membrane(PEM) is the core part of proton exchange membrane fuel cell(PEMFC). The performance of PEM directly determines the life of PEMFC and the efficiency of PEMFC. Nowadays, the most widely used membrane is made by DuPont called Nafion. However, the cost of Nafion membranes is very high, and the proton conductivity of Nafion decreases sharply at high temperature and low humidity. Moreover, the methanol permeability coefficient of Nafion increases sharply at high temperature. Therefore, it is important to find suitable material to replace Nafion membranes.Sulfonated poly(arylene ether)s have suitable thermal stability, desirable chemical stability and low cost. However, high sulfonated degree(Ds) leads to poor dimensional stability and mechanical property as well as high methanol permeability, which hinders its application. Therefore, it is necessary to modify this kind of material. Graphene oxide is similar in structure to graphene, so it has high Young’s modulus, high conductivity and high specific surface area.In this paper,(GO) and sulfonated poly(ether ketone)(SPAEKS) were used to prepare sulfonated poly(arylene ether)s/graphene oxide(SPAEKS/GO) composite membrane. The structure of the target membranes was proved by FT-IR spectrum. The proton conductivity of the composite membrane was improved and the methanol permeability of the membrane decreased a lot. The methanol permeability coefficients and proton conductivity of SPAEKS/GO-10% were 7.65×10-7cm2s-1and 0.045S/cm, respectively at 25 oC,and the proton conductivity is 0.095 S/cm at 80 oC. The scanning electron microscopy images of the membranes showed no obvious phase separation in the composite membranes.We prepared SPAEKS/GO-NH2 composite membranes based on graphene oxide with amino groups(GO-NH2) and SPAEKS. To enhance the proton conductivity further by using the interaction between amino groups and sulfonic acid groups. The proton conductivities of the membranes were 0.047S/cm(25oC) and 0.098S/cm(80oC), respectively, showing high proton conductivity characteristics, which were expected to be used in PEMFC as novel membranes material.