title: Transparent, Ultrahigh-Gas-Barrier Films with a Brick-Mortar-Sand Structure.
abstract: Transparent and flexible gas-barrier materials have shown broad applications in electronics, food, and pharmaceutical preservation. Herein, we report ultrahigh-gas-barrier films with a brick-mortar-sand structure fabricated by layer-by-layer (LBL) assembly of XAl-layered double hydroxide (LDH, X=Mg, Ni, Zn, Co) nanoplatelets and polyacrylic acid (PAA) followed by CO2 infilling, denoted as (XAl-LDH/PAA)n-CO2. The near-perfectly parallel orientation of the LDH "brick" creates a long diffusion length to hinder the transmission of gas molecules in the PAA "mortar". Most significantly, both the experimental studies and theoretical simulations reveal that the chemically adsorbed CO2 acts like "sand" to fill the free volume at the organic-inorganic interface, which further depresses the diffusion of permeating gas. The strategy presented here provides a new insight into the perception of barrier mechanism, and the (XAl-LDH/PAA)n-CO2 film is among the best gas barrier films ever reported.
authors.affiliation: State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, 15 Beisanhuan East Road, Beijing 100029 (China).
authors.forename: Yibo
authors.initials: Y
authors.lastname: Dou
authors.affiliation: State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, 15 Beisanhuan East Road, Beijing 100029 (China).
authors.forename: Ting
authors.initials: T
authors.lastname: Pan
authors.affiliation: State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, 15 Beisanhuan East Road, Beijing 100029 (China).
authors.forename: Simin
authors.initials: S
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, 15 Beisanhuan East Road, Beijing 100029 (China).
authors.forename: Hong
authors.initials: H
authors.lastname: Yan
authors.affiliation: State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, 15 Beisanhuan East Road, Beijing 100029 (China). hanjb@mail.buct.edu.cn.
authors.forename: Jingbin
authors.initials: J
authors.lastname: Han
authors.affiliation: State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, 15 Beisanhuan East Road, Beijing 100029 (China). weimin@mail.buct.edu.cn.
authors.forename: Min
authors.initials: M
authors.lastname: Wei
authors.affiliation: State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, 15 Beisanhuan East Road, Beijing 100029 (China).
authors.forename: David G
authors.initials: DG
authors.lastname: Evans
authors.affiliation: State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, 15 Beisanhuan East Road, Beijing 100029 (China).
authors.forename: Xue
authors.initials: X
authors.lastname: Duan
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D000327:Adsorption; D002245:Carbon Dioxide / Q000737:chemistry*; D003035:Cobalt / Q000737:chemistry; D004058:Diffusion; D005740:Gases / Q000737:chemistry*; D006878:Hydroxides / Q000737:chemistry*; D008274:Magnesium / Q000737:chemistry; D008958:Models, Molecular; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D009532:Nickel / Q000737:chemistry; D015032:Zinc / Q000737:chemistry
chemical_list: D000180:Acrylic Resins; D005740:Gases; D006878:Hydroxides; D002245:Carbon Dioxide; D003035:Cobalt; C006903:carbopol 940; D009532:Nickel; D008274:Magnesium; D015032:Zinc
keywords: brick-mortar-sand structures; carbon dioxide; free volume; gas barrier; layered double hydroxides