Selectivity enhancement of quaternized poly(arylene ether ketone)membranes by ion segregation for vanadium redox flow batteries

论文摘要

Quaternary ammonium densely functionalized octa-benzylmethyl-containing poly（arylene ether ketone）s（QA-OMPAEKs） with ion exchange capacities（IECs） ranging from 1.23 to 2.21 mmol g-1 were synthesized from:（1） Ullmann coupling extension of tetra-benzylmethyl-containing bisphenol A;（2） condensation polymerization with activated dihalide in the presence of K2CO3;（3） selective bromination using N-bromosuccinimide; and（4） quantitative quaternization using trimethylamine. Both smallangle X-ray scattering（SAXS） and transmission electron microscope（TEM） characterizations revealed distinct nano-phase separation in QA-OMPAEKs as a result of the dense quaternization. The QA-OMPAEK-20 with an IEC of 1.98 mmol g-1 exhibited a high SO42- conductivity of 11.4 mS cm-1 and a low VO2+ permeability of 0.06×10-12m2s-1 at room temperature,leading to a dramatically higher ion selectivity than Nafion N212. Consequently, the vanadium redox flow battery（VRFB）assembled with QA-OMPAEK-20 achieved a Coulombic efficiency of 96.9% and an energy efficiency of 84.8% at a current density of 50 mA cm-2, which were much higher than those of the batteries assembled with Nafion N212 and a home-made control membrane without distinct nano-phase separation. Therefore, ion segregation is demonstrated to be a strategical route for the design of high performance anion exchange membranes（AEMs） for VRFBs.

论文目录

• 1 Introduction
• 2 Experimental
•   2.1 Materials
•   2.2 Synthesis of octa-benzylmethyl-containing com-pounds a and b
•   2.3 Copolymerization
•   2.4 Bromination of OMPAEKs
•   2.5 Quaternization of Br-OMPAEKs
•   2.6 Membrane preparation
•   2.7 Characterization
• 3 Results and discussion
•   3.1 Synthesis of octa-benzylmethyl-containing mono-mers
•   3.2 Polymerization and functionalization
•   3.3 Membrane morphology
•   3.4 Water uptake, ion conductivity, and VO2+permeability
•   3.5 Mechanical strength, thermal property, and oxi-dative stability
•   3.6 VRFB performance
• 4 Conclusions

文章来源

类型: 期刊论文

作者: Yu Chen,Zhongcheng Liu,Meijin Lin,Qilang Lin,Bihai Tong,Dongyang Chen

来源: Science China(Chemistry) 2019年04期

年度: 2019

分类: 工程科技Ⅰ辑,工程科技Ⅱ辑

专业: 材料科学,工业通用技术及设备,电力工业

单位: College of Materials Science and Engineering, Fuzhou University,College of Chemistry, Fuzhou University,School of Metallurgy Engineering, Anhui University of Technology

基金: supported by the National Natural Science Foundation of China (51503038,51873037)

分类号: TB383.2;TM912

页码: 479-490

总页数: 12

文件大小: 1019K

下载量: 13