초록 |
Titanosilicate ETS-10 has a 3D ordered microporous structure and is potentially useful as a permselective barrier. Nanocomposite membranes of sulfonated poly(ether ether ketone) (SPEEK) and microporous titanosilicate ETS-10 were prepared with various mass ratio by solution casting for vanadium redox flow battery application. The scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy images of the composite membrane showed the presence and the uniformity dispersion of ETS-10 in the SPEEK polymer matrix. The water uptake, swelling ratio, mechanical property, proton conductivity, vanadium ion permeability and VRB single cell tests of the composite membrane were characterized in detail. The composite membrane with 4 wt% ETS-10 showed the VRB single cell performance of CE 98.5 % and EE 83 % at 60 mA cm-2 resulting from low vanadium permeability without proton conductivity loss, while Nafion 117 membrane showed the cell performance of CE 97.6 % and EE 77 %. Furthermore, the composite membrane with 4 wt% ETS-10 exhibited high capacity retention and maintained efficiency during 100 cycles at 40 mA cm-2. The results indicated that ETS-10 particle is suitable as a permselective barrier for reducing vanadium crossover and improving cell performance. |