Halloysite nanotube-based nanofiber coatings with Ag-Cu nanoclusters for dual antimicrobial and anticorrosion applications

Microbiologically influenced corrosion (MIC) accelerates the degradation of metal components in marine and water-handling systems, creating a need for coatings that combine barrier protection with antimicrobial activity. Here, we report a dual-function nanofiber coating in which Ag-Cu bimetallic nanoclusters are immobilized within halloysite nanotubes (Ag-CuNC/halloysite nanotube (HNT) ) and embedded into electrospun polycaprolactone (PCL) nanofibers to form conformal coatings on copper. In artificial seawater, the nanocomposite coating improved corrosion performance under both abiotic and Lysinibacillus sp. -inoculated conditions by increasing charge-transfer resistance and yielding the lowest corrosion current densities. Notably, bare copper reached 17. 8 × 10 −6 A cm −2 after 7 days, while neat PCL nanofibers reduced this value to 7. 29 × 10 −6 A cm − 2, and Ag-CuNC/HNT–PCL provided the strongest protection. The coating also stabilized the corrosion medium pH close to the initial value in abiotic tests and mitigated acidification in biotic tests. Ag-Cu nanoclusters exhibited broad-spectrum antimicrobial activity against Escherichia coli, Staphylococcus aureus, and Candida albicans, and inhibited Pseudomonas aeruginosa biofilm formation by 94. 5% as free nanoclusters and 61% when incorporated into nanofiber coatings. Structural analyses confirmed successful dispersion of Ag-CuNC/HNT within the nanofiber matrix, supporting a scalable strategy for MIC mitigation and antimicrobial surface protection in marine environments.