In the field of proton exchange membranes (PEMs), it is still a great challenge to explore new Nafion alternatives, maintaining the high proton conductivity and lowering the cost of practical application. In this work, a series of low sulfonated poly(aryl ether ketone sulfone) (SPAEKS) membranes hybridized by [Bi 6 O 5 (OH) 3 ] 2 (NO 3 ) 10 ⋅6H 2 O (H 6 Bi 12 O 16 ) have been successfully fabricated. When the doping amount of H 6 Bi 12 O 16 reaches 5 wt%, the DS15-Bi 12 -5 showing the best proton conductive ability and mechanical properties. The proton conductivity can achieve 72.8 mS⋅cm −1 at 80 • C and the tensile strength can reach 43.57 MPa. Confirmed by experimental data and activation energy (E a ) calculations, the existence of Bi cluster makes more hydrogen bonds, providing additional proton hopping sites and offers more proton transport vehicles, leading to a high proton conduction performance. This work proved that polyoxometalates (POMs) can replace the role of sulfonate groups in SPAEKS to a certain extent and work out the defects of high sulfonation, making a remarkable contribution to the practical application of low sulfonated SPAEKS.

No abstract