An active self–healing and UV–resistant anticorrosion coating based on loading–enhanced nanocontainers tailored for Q235 carbon steel protection

Abstract

Complex self–healing methods and limited UV resistance restrict the application of reactive organic protective coatings for intelligent corrosion–protection in harsh marine environments. To address this, ultra–high aspect ratio boron nitride nanosheets (BNNS) were developed for uniform growth of polydopamine (PDA), loaded with benzotriazole (BTA). These BNNS/PDA/BTA (BPB) nanocontainers achieved high BTA loading (168.4 μg/mg) with efficient pH–sensitive release and excellent corrosion resistance (1.41 × 10¹⁰ Ω·cm²). After 30 days of immersion, the corrosion–rate of modified epoxy coatings was only 1.25 × 10⁻⁵ mm/year, and UV absorption of BPB maintained coating stability under prolonged exposure. This work informs heavy–duty anti–corrosion applications.