Porous organic polymer with high-density phosphoric acid groups as filler for hybrid proton exchange membranes

Developing sulfonated poly (ether ether ketone) (SPEEK)-based proton exchange membrane with both high proton conductivity and robust mechanical stability is desired for proton exchange membrane fuel cell (PEMFC). Here, a type of phosphoric acid porous organic polymer (PAPOP) with high-density phosphoric acid (-PO3H2) groups and microporous structure was synthesized and incorporated into SPEEK matrix. The porous skeleton bonding-PO3H2 groups of PAPOP reduced the proton transfer activation energy by providing additional proton conduction pathways. The rigid backbone of PAPOP and its good compatibility with SPEEK increased the me-chanical strength of the membrane. The hybrid membrane achieves greatly enhanced proton conductivity up to 417.0 mS cm-1 (80 degrees C, 100% RH) and high tensile strength of 120.6 MPa. The maximum power density of fuel cell with the hybrid membrane exhibits two times increase compared with the control membrane.

Automated summary

Developing a sulfonated poly (ether ether ketone) (SPEEK)-based proton exchange membrane with high proton conductivity and robust mechanical stability is desired for proton exchange membrane fuel cells (PEMFCs). In this study, a phosphoric acid porous organic polymer (PAPOP) with high-density phosphoric acid groups and microporous structure was synthesized and incorporated into the SPEEK matrix. The hybrid membrane showed greatly enhanced proton conductivity and mechanical strength, resulting in a two times increase in the maximum power density of the fuel cell compared to the control membrane.