文献类型：期刊文献

英文题名：Insights into High Li+/Mg2+Separation Performance Using a PEI- Grafted Graphene Oxide Membrane

作者：Wang, Shuai[5];Zhu, Liuyuan[5];Yang, Rujie[5];Li, Minliang[2];Dai, Fangfang[1,3];Sheng, Shiqi[5];Chen, Liang[2,4];Liang, Shanshan[6,7]

机构：[1]Univ Chinese Acad Sci, Wenzhou Inst, Wenzhou 325000, Peoples R China;[2]Zhejiang A&F Univ, Opt Mech & Elect Engn, Hangzhou 311300, Peoples R China;[3]Zhejiang Lab Regenerat Med Vis & Brain Hlth, Oujiang Lab, Wenzhou 325001, Peoples R China;[4]Ningbo Univ, Sch Phys Sci & Technol, Ningbo 315211, Peoples R China;[5]East China Univ Sci & Technol, Sch Phys, Shanghai 200237, Peoples R China;[6]East China Univ Sci & Technol, Sch Phys, Shanghai 200237, Peoples R China;[7]East China Univ Sci & Technol, Natl Engn Res Ctr Ind Wastewater Detoxicat & Resou, Shanghai 200237, Peoples R China

年份：2023

卷号：127

期号：14

起止页码：6981

外文期刊名：JOURNAL OF PHYSICAL CHEMISTRY C

收录：;EI(收录号：20231413846636);WOS:【SCI-EXPANDED(收录号:WOS:000965709300001)】；

基金：ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China (12004110, 11974366, 12004109, and 12005062) and the Fundamental Research Funds for the Central Universities.

语种：英文

外文关键词：Grafting (chemical) - Graphene - Membrane technology - Permeation - Polyelectrolytes - Swelling

摘要：Lithium extraction from brine or seawater using membrane technology has attracted extensive attention in recent years. Graphene oxide (GO), as one of the two-dimensional materials, has been proven as a competitive candidate for membranes. However, the GO membranes still suffer challenges for ion sieving due to the swelling in the aqueous solution. In this work, a GO-PEI membrane with positively charged channels was constructed by polyelectrolyte polyethyleneimine (PEI) molecular chain-grafted GO nanosheets. The GO-PEI membrane showed a high selectivity of 22.2 for Li+/Mg2+, together with a competitive Li+ permeation rate of 0.09 mol m-2 h-1 in a binary permeation test. In addition, the membrane showed excellent stability during the separation process. The enhanced Li+/Mg2+ separation performance of the GO-PEI membrane could be mainly attributed to the synergistic effect of size sieving and electrostatic repulsion. We further systematically studied the influence of various variables, such as PEI molecular weight, PEI content, membrane thickness, and ion concentration, on separation performance. This work deepens the understanding of membrane ion selectivity from multiple perspectives and puts forward a strategy to design a two-dimensional membrane structure from microscopic materials.