Nanocomposite Proton Conducting Membranes Based On Nanoscale Ionic Materials

In the context of global environmental pollution and energy shortages,it is urgent to find a clean and efficient energy technology to achieve sustainable development.Fuel cell is a kind of energy conversion technology that can directly convert chemical energy into electricity without pollutants,showing great application prospects.The Proton exchange membrane is the core component of the fuel cell and directly determines its output performance.In this study,two-dimensional nanoscale ionic materials based on graphene oxide and zero-dimensional nanoscale ionic materials based on silica were designed and synthesized.The nanoscale ionic materials were blended with sulfonated polymer matrix to prepare nanocomposite membranes.This study explored the effect of chemical microenvironment,water environment and physical microenvironment on proton conduction and the main research results are as follows:The manipulation of chemical microenvironment and water environment for intensification of proton conduction under low humidity.Graphene oxide-based nanoscale ionic materials(NIMs-GO)were prepared and doped into sulfonated polysulfone to fabricate nanocomposite membranes.Water-retaining PEG segments and-SO₃H/-NH₂ acid-base pairs on NIMs-GO greatly improved the proton conduction of the membrane under low humidity.At 40%RH,75?,the proton conductivity of SPSF/NIMs-GO reached 0.037 S cm-¹,24 times higher than that of SPSF membrane.The manipulation of physical microenvironment for intensification of proton conduction.The silica-based nanoscale ionic materials(NIMs-SiO₂)were prepared and doped into the sulfonated poly(ether ether ketone)(SPEEK)to obtain nanocomposite membranes.NIMs-SiO₂ promoted the microphase separation in the membrane to form continuous ion transport channels.It was found that the proton conductivity of the SPEEK/NIMs-SiO₂(5.28)nanocomposite membrane was greatly improved after the formation of proton transport channels,and the proton conductivity was 0.22 S cm^-1 at70?,which is 92%higher than that of pure SPEEK membrane.