Synergistic effect of graphene oxide and cathodic protection to enhance the long-term protective performance of organic coatings

• Published in: Journal of materials science 2023-07, Vol.58 (26), p.10853-10869
• Main Authors: Sun, Tianxiang, Jin, Kai, Wang, Tong, Wang, Wei, Li, Wen, Gao, Hui, Sun, Lifang, Chen, Shougang
• Format: Article
• Language: English
• Subjects: Cathodic protection; Characterization and Evaluation of Materials; Chemistry and Materials Science; Classical Mechanics; Comparative analysis; Corrosion; Corrosion and anti-corrosives; Corrosion mechanisms; Corrosion prevention; Corrosion products; Crystallography and Scattering Methods; Diffusion coating; Diffusion coefficient; Epoxy resins; Graphene; Graphite; Marine engineering; Marine environment; Materials Science; Metals & Corrosion; Organic coatings; Oxide coatings; Polymer Sciences; Protection and preservation; Protective coatings; Service life; Solid Mechanics; Synergistic effect
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-023-08701-2

Graphite oxide (GO)-based organic coating and cathodic protection are effective methods for improving the service life of metals in the marine environment. However, few kinds of researches focus on long-term protective performance for coatings combined with cathodic protection potential and GO doping. In this work, the protective effects of epoxy (EP) coatings with different charge characteristics of GO addition and cathodic protection potential were compared and analyzed, and it is proposed that the accumulation of negative charges in cathodic protection would further enhance the electrostatic repulsive force of negatively charged GO against corrosive media. The long-term protective properties are systematically analyzed by EIS, Cl − diffusion analysis, and corrosion product observation. The GO/EP composite coating combined with − 1.2 V (vs. SCE) negative cathodic protection potential performed the biggest capacitance arc radius, the lowest Cl − diffusion coefficient, and no corrosion trace. The low-frequency impedance value increased from 1.5 × 10 8 Ω·cm 2 to 3 × 10 8 Ω·cm 2 in 60 days test period. In addition, the corrosion inhibition mechanism of the synergistic of GO nanosheet and negative cathodic protection potential on EP coating was revealed. This research result performs important reference significance for the application of GO material in the field of marine anti-corrosion engineering. Graphical Abstract