Transparency anticorrosion coatings prepared from alumina-covered graphene oxide/polyimide nanocomposites

Abstract

In this study, a novel alumina-covered graphene oxide/polyimide (AlGO/PI) nanocomposite was developed as an anticorrosion coating material. The hydroxyl groups on GO reacted with aluminum isopropoxide via a sol-gel process to yield AlGO nanosheets. The characterization and structure were confirmed by Fourier transform infrared spectrometry, X-ray photoelectron spectroscopy, field emission scanning electron microscopy, and field emission transmission electron microscopy. Subsequently, GO and AlGO were incorporated into a PI matrix, leading to the formation of GO/PI and AlGO/PI nanocomposites. Well-dispersed AlGO nanosheets in the PI matrix acted as effective additives to enhance the water barrier properties of GO/PI (58 g/(m 2 •day)) and AlGO/PI (43 g/(m 2 •day)) coatings. Most importantly, the resultant AlGO/PI films exhibited excellent optical transparency (>75%) and anticorrosion properties. Electrochemical measurements of corrosion potential, polarization resistance, and corrosion current as well as electrochemical impedance spectroscopy confirmed that the AlGO/PI nanocomposites exhibited better anticorrosion properties than GO/PI nanocomposites. This is likely because the insulating layer of alumina on GO can isolate the charge transfer pathway between GO and the metal substrates, leading to improved anticorrosion behavior.

Application of electroactive Au/aniline tetramer–graphene oxide composites as a highly efficient reusable catalyst

“…GO was prepared from graphite by the modied Hummers method. 24,25 3 g of graphite was mixed with 360 mL H 2 SO 4 and 40 mL H 3 PO 4 in a ask, and the temperature was raised to 50 C followed by the addition of 18 g of KMnO 4 . The mixture was continuously stirred overnight, and then 10 mL of H 2 O 2 was added into the mixture.…”

“…From the FTIR spectrum of GO, the peak at 1041 cm À1 was ascribed to C-O-C bonding, and the peaks at 3373, 1725, and 1620 cm À1 signied the presence of -OH, C]O, and C]C functional groups, respectively, which indicates that abundant oxygencontaining groups existed on the surface of GO. 24,27 The peak between 3314 and 3209 cm À1 can be attributed to the N-H stretching vibration, while those at 3032 cm À1 can be attributed to the C-H stretching vibration. 28 The AT showed N]Q]N (quinoid ring) and N]B]N (benzenoid ring) bands at 1594 and 1504 cm À1 , respectively.…”

Steady-State Conduction Current Performance for Multilayer Polyimide/SiO2 Films

“…Polyimide (PI) films are a widely used insulating material for engineering industries. These thin films are mainly used in electronic devices, multilayer surface coatings on metals, coatings on intermetallic compounds, temperature protection blankets in space crafts and magnetic wire enamelling for electric motor insulation [ 1 , 2 ]. PI thin films are also used for sensor coatings and composite electrodes for batteries [ 3 , 4 , 5 , 6 , 7 , 8 ].…”

“…We can use Equation (2) to describe the conduction phenomenon. The time needed to obtain the steady-state current relies on the material's nature, the applied electric field and the temperature.…”

A Novel Electroactive Imide Oligomer and Its Application in Anticorrosion Coating

“…Metallic corrosion is a serious safety and economic issue for construction and industrial development [1]. Many approaches to corrosion protection have been developed, including organic coatings [2][3][4][5], inorganic coatings [6,7], ceramic coatings [8], and corrosion inhibitors [9,10]. Recently, organic coatings have attracted significant attention due to their potential for simple preparation, low cost, and functional potential, while being considered one of the most efficient strategies for corrosion protection.…”