Facile Preparation of Water-Dispersible Graphene Sheets Stabilized by Carboxylated Oligoanilines and Their Anticorrosion Coatings

Abstract

Dispersion of graphene in solvents is of crucial importance toward its practical applications. In this study, using a water-soluble carboxylated aniline trimer derivative (CAT(-)) as a stabilizer, the commercial graphene can be stably dispersed in water at high concentration (>1 mg/mL) via strong π-π interaction that was proved by Raman and UV-vis spectra. Moreover, the CAT(-)-functionalized graphene sheets (G-CAT(-) hybrid) exhibited high conductivity (∼1.5 S/cm), good electroactivity and improved electrochemical stability. The addition of well-dispersed graphene into waterborne epoxy system (G-CAT(-)/epoxy) remarkably improved corrosion protection compared with pure waterborne epoxy coating, based on a series of electrochemical measurements performed under 3.5% NaCl solution. This significantly enhanced anticorrosion performance is mainly due to the improved water barrier properties derived from highly dispersed graphene nanosheets in the epoxy coating.

Enhancing the Corrosion Resistance of Epoxy Coatings by Impregnation with a Reduced Graphene Oxide‐Hydrophobic Ionic Liquid Composite

“…A higher R ct implied less number of corrosive electrolytes were transported into coatings . As seen in Table , R ct was increased with addition of material because of the barrier function of the coating was gradually being exerted . Meanwhile, the value of R pore for RGO‐IL coating was higher than sore RGO sample which can be explained by the good dispersity of RGO in coating and improving coating electrical resistance against transfer of corrosive species through the pores of coating.…”

“…[49] As seen in Table 2, R ct was increased with addition of material because of the barrier function of the coating was gradually being exerted. [50] Meanwhile, the value of R pore for RGO-IL coating was higher than sore RGO sample which can be explained by the good dispersity of RGO in coating and improving coating electrical resistance against transfer of corrosive species through the pores of coating. CPE dl as constant phase of the double layer was the non-ideal capacitance between the working electrode and coating, while the charge transfer resistance R ct was in parallel with CPE dl , which showed that the electrolyte permeates at the surface of Q235.…”

Degradation of Toxic Organic Contaminants by Graphene Cathode in an Electro‐Fenton System

“…EIS is a rapid, in situ and non-destructive technique for investigating the electrochemical properties of the electrode surface and affording information on the impedance changes of the electrode surface during the modification process [16,17]. Figure 4 illustrated the Nyquist diagrams and Bode plots of the CuO-graphene cathode under different reduction potentials in 10 g/L Na 2 SO 4 solution.…”

Effect of graphene on the electrochemical protection of zinc‐rich coatings

“…[14] Recently, considerable amount of papers have reported that the graphene/polymer composite possesses enhanced barrier properties that are beneficial for high anticorrosion performances. [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] Unlike carbon nanotubes that can only provide similar mechanical benefits, [10] these lightweight sheets can reduce oxygen permeability of host membranes. [15,31] It also should be noted that the graphene process outstanding electrical conductivity, [32][33][34] which can increase the conductivity of coatings when doped into the polymer matrixes.…”