Composite membranes based on sulfonated poly(ether ether ketone) and SDBS-adsorbed graphene oxide for direct methanol fuel cells

Sodium dodecylbenzene sulfonate (SDBS) adsorbed graphene oxide (GO) has been used as a filler to modify sulfonated poly(ether ether ketone) (SPEEK). The incorporation of SDBS-GO greatly increases the ion-exchange capacity (IEC), water uptake, and proton conductivity, while it reduces the methanol permeability through the SPEEK membranes. With well controlled contents of SDBS-GO, the composite membranes exhibit higher IEC, water uptake, and proton conductivity and lower methanol permeability than Nafion (R) 112, making them attractive as proton exchange membranes (PEMs). These superior characteristics make the composite membranes with optimized SDBS-GO contents exhibit superior performance in direct methanol fuel cells (DMFCs) compared to the plain SPEEK or Nafion (R) 112 membranes.