Preparation and properties of proton exchange membrane reinforced by metal-organic framework/ionic liquid

Abstract

To improve the proton conductivity of the sulfonated polyether ether ketone/ionic liquid （SPEEK/IL） membrane and reduce the loss rate of IL in the membrane， Cd@Co-MOF-74/Phosphate-4-phenylimidazole ionic liquid （［IM2］［H2PO4］）/SPEEK ternary composite membranes were prepared by the solution casting method. Results show that due to the formation of hydrogen bonds between the imidazole ring in ionic liquids and the —OH or carboxylic acid groups in MOF， imidazole molecules are anchored on the pore walls of MOF. The proton conductivity of the ternary composite membrane at 120 ℃ is the highest， reaching 26.93 mS·cm-1， when the mass fraction of the Cd@Co-MOF-74 doping is 1.5%. The IL loss rate of bimetallic MOF/IL/SPEEK ternary composite membranes with different contents is generally between 20% and 25%. Doping bimetallic MOFs in SPEEK/IL membranes ensures high proton conductivity while reducing the swelling rate of SPEEK/IL composite membranes， thereby increasing their service life.

Keywords

• speek
• ionic liquid
• mof
• proton exchange membrane
• proton conductivity