Nano-modified epoxy coatings: An effective method for sustainable construction

Corrosion in reinforced concrete (RC) structures is an increasingly prevalent issue in the construction industry. Thus, reducing corrosion and strengthening concrete structure would help sustain the environment. This study is centred around the development of epoxy coatings modified with nano-clay and graphene derivatives including multi-walled CNT (Graphene Oxide (GO), and reduced Graphene Oxide (rGO)). Prepared coatings matrix applied on mild steel bar and embedded in concrete specimen for testing for accelerated corrosion. The study evaluated the effectiveness of epoxy coatings modified with nanoparticles using various non-destructive methods, including visual inspection, impressed current corrosion testing, and ultrasonic-guided wave measurements. The non-destructive testing results were further supported by the findings from destructive testing. Ultrasonic studies showed that nano-clay coating is 1.5 times better than PE, however GO/CNT showed no corrosion onset after 60 days of corrosion testing. PE coatings lost 2–3% more mass than nano-clay coatings, while GO/CNT coatings lost 98% less mass as represents in destructive testing. Nano-clay coatings minimize tensile strength loss by 9% than PE coatings, whereas GO/CNT coatings lower it by 98–99%. Overall, graphene-based coatings are more effective in corrosion inhibition than nano-clay coatings. Suggested modification increase infrastructure life by several factors and reduces maintenance, promoting sustainable construction.