| 초록 |
The proton conductive membranes were prepared by impregnating sulfonated poly(arylene ether ketone) (SP) into the porous polytetrafluoroethylene (PTFE) substrates for vanadium redox flow battery. To impregnate SP, the surface of porous PTFE was chemically hydrophilized with catechol and polyethyleneimine (PEI). The SP filled PTFE membranes (trPTFE/SP) showed significantly enhanced thermal, dimensional, and mechanical stability. While the water uptake of trPTFE/SP membranes reduced by only 3 ~ 5 %, the swelling ratio reduced to about a half and tensile strength increased by 5 times. Also, they revealed hugely decreased vanadium ion permeability, which was from 5 times to 15 times lower than that of Nafion117. This low vanadium permeability led to high coulombic efficiency over 96 % and energy efficiency around 84 % during the 100 charge-discharge cycling tests, which are better than Nafion 117 membrane. |
