Enhancement of Hydrophobic, Resistive Barrier and Anticorrosion Performance of Epoxy Coating with Addition of Clay-modified Green Silico-Graphitic Carbon

In this study, a straightforward method for producing clay-modified silico-graphitic carbon (CGSGC) was developed and applied to create CGSGC/epoxy coatings for carbon steel (CS). The CGSGC was synthesized using a mixture of 25% pond clay and 75% remnant agricultural biomass through pyrolysis. The aim was to evaluate the barrier and anti-corrosion properties of these coatings in a 3.5 wt.% solution. The results demonstrated that adding 0.1 wt.% of CGSGC in the epoxy (EP) matrix enhanced its anti-corrosion inhibition capabilities with 99.8% compared to standard EP coating. The 0.1 wt.% CGSGC/EP mixed coating exhibited robust hydrophobicity with WCA of 142.2° and thermal stability up to 250°C with 2-3% weight reduction. The microhardness of the optimized sample shows a 59.18% improvement compared to standard EP coating. SEM images revealed improved EP compactness and reduction in microstructural defects (holes and cracks), with the incorporation of 0.1 wt.% CGSGC. 3D profilometry showed a smoother surface for the 0.1 wt.% CGSGC/EP coating. These materials can be a safer alternative to conventional hazardous chemicals for protecting carbon steel from corrosion.