title: Tuning nanostructure of graphene oxide/polyelectrolyte LbL assemblies by controlling pH of GO suspension to fabricate transparent and super gas barrier films.
abstract: A technique of layer-by-layer (LbL) self-assembly was used to prepare transparent multilayered gas barrier films consisting of graphene oxide (GO)/branched poly(ethylenimine) (BPEI) on a poly(ethylene terephthalate) substrate. The effect of the GO suspension pH on the nanostructure and oxygen barrier properties of the GO/BPEI film was investigated. The oxygen barrier properties of the assemblies were shown to be highly dependent on the pH. It was demonstrated that the film assemblies prepared using a GO suspension with a pH of 3.5 exhibited very dense and ordered structures and delivered very low oxygen transmission rates (the lowest was <0.05 cm(3) m(-2) day(-1)). The assemblies were characterized with ultraviolet-visible spectroscopy and ellipsometry to identify the film growth mechanism, and the result indicated a linear growth behavior. To analyze the nanostructure of the films, atomic force microscopy, transmission electronic microscopy, and grazing incidence wide-angle X-ray diffraction were used.
authors.affiliation: R&D Center for Membrane Technology and Department of Chemical Engineering, Chung Yuan University, Chung-Li 32023, Taiwan. cchu@cycu.edu.tw.
authors.forename: Jung-Tsai
authors.initials: JT
authors.lastname: Chen
authors.forename: Ywu-Jang
authors.initials: YJ
authors.lastname: Fu
authors.forename: Quan-Fu
authors.initials: QF
authors.lastname: An
authors.forename: Shen-Chuan
authors.initials: SC
authors.lastname: Lo
authors.forename: Shu-Hsien
authors.initials: SH
authors.lastname: Huang
authors.forename: Wei-Song
authors.initials: WS
authors.lastname: Hung
authors.forename: Chien-Chieh
authors.initials: CC
authors.lastname: Hu
authors.forename: Kueir-Rarn
authors.initials: KR
authors.lastname: Lee
authors.forename: Juin-Yih
authors.initials: JY
authors.lastname: Lai
mesh_terms: D005740:Gases / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D049329:Nanostructures / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry; D010100:Oxygen / Q000737:chemistry; D011093:Polyethylene Terephthalates / Q000737:chemistry; D011094:Polyethyleneimine / Q000737:chemistry
chemical_list: D005740:Gases; D010087:Oxides; D011093:Polyethylene Terephthalates; D006108:Graphite; D011094:Polyethyleneimine; D010100:Oxygen