Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
4989121 | Journal of Membrane Science | 2017 | 42 Pages |
Abstract
In this work the degradation behavior of sulfonated polyimide-hydrogen type (SPI-H) membrane for vanadium redox flow battery (VRFB) usage was investigated through in-situ and ex-situ measurements. Morphological, mechanical and physico-chemical properties, together with structure information of the SPI-H membrane or its oligomer before and after degradation were characterized. Both optical photographs and SEM images show more serious destruction of surface morphology of SPI-H membrane during in-situ degradation than ex-situ one. Decrease in mechanical property and viscosity average molecular weight of SPI-H membrane after degradation in different immersion solutions verifies that both H+ and V(V) play important roles in accelerating the decomposition. FTIR results demonstrate that -SO3H groups of SPI-H membrane in VRFB aren't destructed. 1H-NMR spectra verify the scission of polymer chain and the hydrolysis of imide ring of SPI-H membrane after degradation. XPS spectra evidence the oxidation of -NH2 groups of one hydrolysis product of SPI-H. According to all the experimental results, the 2-step degradation mechanism including hydrolysis and oxidation of SPI-H membrane in VRFB is proposed.
Keywords
tetramethylsilaneTMSVRFB1H-NMRPODHydrogen nuclear magnetic resonanceSPESsPEEKODAIEMVanadium redox flow batteryCoulomb efficiencyEnergy efficiencyFourier transform infraredtriethylamineDegree of sulfonationVoltage efficiencyFTIRX-ray photoelectron spectroscopyXPSMembraneIon exchange membraneSEMDegradation mechanismscanning electron microscopeSulfonated polyimideSulfonated poly(ether sulfone)Sulfonated poly(ether ether ketone)TEA
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Filtration and Separation
Authors
Xiaodong Huang, Yang Pu, Yuqin Zhou, Yaping Zhang, Hongping Zhang,