A novel SPEEK/PW11V/rGO hybrid film for proton conduction

• A novel SPEEK/PW11V/rGO hybrid film was prepared.
• It shows a good proton conductivity of 2.22 × 10− 2 S cm− 1 at ambient condition.
• It is a new solid high proton conductor.
• Conduction mechanism has been investigated.

A SPEEK/PW11V/rGO hybrid film was prepared by a simple method through sulfonated polyether ether ketone (SPEEK), tungstovanadophosphoric acid (H4PW11VO40, abbreviated as PW11V) and reduced graphene oxide (rGO) in this work. The results indicate that the Keggin framework of PW11VO404 − anion still remain in the hybrid film and confirm the homogeneous dispersion of PW11V on the surface of graphene sheet, which results in a better stability of PW11V. The electrochemical impedance spectroscopy shows that this film exhibits high proton conductivity of 2.22 × 10− 2 S cm− 1 at 17 °C and 6.43 × 10− 2 S cm− 1 at 65 °C (65% relative humidity). Its activation energy value for proton conduction is 18.9 kJ mol− 1, suggesting that the conduction mechanism for this film is a mix of Vehicle mechanism and Grotthuss mechanism. It is an alternative film material which may be applied in the field of fuel cells.