Layer-by-layer assembled graphene oxide films and barrier properties of thermally reduced graphene oxide membranes

Abstract

In this study, we present a facile method of fabricating graphene oxide (GO) films on the surface of polyimide (PI) via layer-by-layer (LBL) assembly of charged GO. The positively charged amino-phenyl functionalized GO (APGO) is alternatively complexed with the negatively charged GO through an electrostatic LBL assembly process. Furthermore, we investigated the water vapor transmission rate and oxygen transmission rate of the prepared (reduced GO [rGO]/rAPGO) 10 deposited PI film (rGO/rAPGO/PI) and pure PI film. The water vapor transmission rate of the GO and APGO-coated PI composite film was increased due to the intrinsically hydrophilic property of the charged composite films. However, the oxygen transmission rate was decreased from 220 to 78 cm 3 /m 2 ·day·atm, due to the barrier effect of the graphene films on the PI surface. Since the proposed method allows for large-scale production of graphene films, it is considered to have potential for utilization in various applications.

Mixed Dye Removal Efficiency of Electrospun Polyacrylonitrile–Graphene Oxide Composite Membranes

“…The background subtracted Raman spectra shown in Figure S4 confirmed the successful preparation of GO, cGO, and cGO–PAN composite nanofibers by examining the ratio of D- and G-bands. While the D/G peak ratio for the bare GO was examined to be 0.88, which was within the literature values [ 41 , 42 , 43 , 44 ], the ratio slightly increased to 0.92 and 0.93 upon modification with CTAC and PAN, respectively. It has been reported that the modification of GO (e.g., covalent organic/polymer modifier and chemical doping) often leads to a notable increase of the D-band (i.e., more defects and disordered structure), resulting in the increase of the D/G ratio [ 43 , 44 ].…”

“…While the D/G peak ratio for the bare GO was examined to be 0.88, which was within the literature values [ 41 , 42 , 43 , 44 ], the ratio slightly increased to 0.92 and 0.93 upon modification with CTAC and PAN, respectively. It has been reported that the modification of GO (e.g., covalent organic/polymer modifier and chemical doping) often leads to a notable increase of the D-band (i.e., more defects and disordered structure), resulting in the increase of the D/G ratio [ 43 , 44 ]. The marginal increase of D/G ratios for our cGO and cGO–PAN composite nanofibers could be due to the relatively weak modification between the GO and the modifiers via electrostatic and physical interactions.…”

Effective immobilization of gold nanoparticles on core–shell thiol-functionalized GO coated TiO2 and their catalytic application in the reduction of 4-nitrophenol

“…In addition, titanium glycolate was transformed to TiO 2 by hydrolysis. We assume that although thiol-functionalized graphene wrapped titanium glycolate presents new properties, the thin graphene oxide layer induces good water transmittance to the new composite [37,38]. The presence of amorphous TiO 2 and gold was confirmed from the XRD pattern and EDS analysis shown in Fig.…”

Facile preparation of a Ag/graphene electrocatalyst with high activity for the oxygen reduction reaction

“…32 Meanwhile, the low I D /I G value of graphene veries that the sample is graphene rather than graphene oxides (GO) since the ratio of I D /I G for GO is close to 1.0. 33 Second, the 2D band shis from 2762 cm À1 to 2711 cm À1 , and the G band shis from 1585 cm À1 to 1588 cm À1 for graphene and Ag/graphene, respectively. This can be attributed to the inuence of electron properties during the double resonance process, 34,35 and indicates n-doping of graphene with Ag deposition.…”