Improving the proton conductivity of proton exchange membranes via incorporation of HPW-functionalized mesoporous silica nanospheres into SPEEK

A highly stable composite proton exchange membrane (PEM) was developed by loading phosphotungstic acid in mesoporous silica nanospheres (HPW@MSNs) and blending with sulfonated poly (ether ether ketone) (SPEEK). The SPEEK/HPW@MSNs-0.5 membrane exhibits enhanced comprehensive performance, such as improved and stable proton conductivity and increased methanol barrier property. The proton conductivity decreased by 15.10% after 240 h at 60 °C and was 1.9 times lower than that of the SPEEK/HPW membrane. The selectivity of the SPEEK/HPW@MSNs-0.5 membrane was about 2.0 times that of the pure SPEEK membrane and 3.4 times that of the SPEEK/HPW membrane.