Abstract: Surface-adhering biofilms contribute significantly to irreversible biofouling and corrosion, presenting a multi-trillion-dollar annual problem in public health and industry. Strategies employing antibacterial elements are emerging to fabricate multifunctional coatings that effectively combat such microbially produced damage. However, rapid, reliable, and robust surface engineering remains challenging due to stability limitations and intricate anti-biofilm additive dynamics. Herein, a silver-capsule-conjugated polyurethane coating with high stability and antimicrobial efficacy in a cooperative manner is developed through controlled supramolecular self-assembly. Polyvinylpyrrolidone (PVP)-mediated molecule entanglement breaks through the incompatibility between polymeric components and nanomaterials, strengthening the dispersion and fixation of encapsulated silver nanoparticles. The facilitation and control of the nanoscale interfacial binding significantly suppresses the aggregation of inorganic nanoparticles and consequent microcracks development, giving rise to mechanical robustness and thermal stability of the hybrid coating under extreme conditions. A synergistic combination of exposed residues, electrostatic, and coordination interactions could readily integrate the resultant coating on virtually arbitrary material surfaces. This composite coating exhibits broad-spectrum and high bactericidal efficiencies of 99.99 % against Staphylococcus aureus and Escherichia coli, as well as excellent biofilm formation suppression. Moreover, our coating has robust resistance to microbial-influenced corrosion (MIC) and can even endure 720 h of salt spray. This study deciphers a general code for creating stable and durable nanohybrid coatings to mitigate microbially related risks.

Key words: Ag encapsulation, Supramolecular interactions, Antibacterial activity, Anti-biofilm, Anti-microbial corrosion, ROS formation