Li+ Selectivity of Carboxylate Graphene Nanopores Inspired by Electric Field and Nanoconfinement. Issue 48 (5th March 2021)

• Record Type: Journal Article
• Authors: Li, Yingying; Yue, Xingyi; Huang, Gen; Wang, Mei; Zhang, Qingwen; Wang, Chunchang; Yi, Haibo; Wang, Shuangyin
• Is Part Of: Small. Volume 17:Issue 48(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-03-05
• Subjects: dehydration -- electric field -- graphene nanopore -- ion association -- ion selectivity; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.202006704
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract: The regulation of the ion selectivity by electric field and ion association on the Li + selectivity of carboxyl functionalized graphene nanopores are investigated by molecular dynamics simulation. Carboxylate graphene nanopores of sub‐2 nm exhibit excellent Li + selectivity under the electric field of 1.0 V nm −1 . The results show that ion association inspired by electric field may be a key factor affecting ion selectivity of sub‐2 nm nanopores. The ion association of Mg 2+ and Cl − can be promoted obviously near the nanopores under the electric field of 1.0 V nm −1 . The migrating of Mg 2+ can be retarded by stable clusters of Mg 2+ and Cl − formed near nanopores. The degree of association of Li + with Cl − is relatively low and the disassociation of the Li + cluster is easier so that Li + can more easily pass through the nanopores. These results gain insight into the effect of ion association inspired by electric field and nanoconfinement of graphene nanopore on Mg 2+ /Li + separation, and provide helpful information for the application of nanoporous materials in extraction of Li + ion from salt‐lake brine. Abstract : Mg 2+ selectivity for graphene nanopores (sub‐2 nm) is attributed to ion hydration characteristics. Sub‐2 nm nanopore exhibits excellent Li + selectivity under 1.0 V nm −1 . Unique Li + selectivity can be attributed to ion association under moderate electric field. Ion association may also be a key factor affecting ion selectivity of graphene nanopore under a certain electric field.