Enhanced photocathodic antifouling/antibacterial properties of polyaniline-Ag-N-doped TiO2 coatings

摘要

Currently, there is tremendous interest in the development of surface coatings for outdoor applications that are self-cleaning with strong antibacterial properties. Herein, aniline was polymerized in situ with silver-N-doped TiO2 composites to fabricate PANI-Ag-N-TiO2 nanocomposites, which were then mixed with an acrylic resin to form coatings on type 316L stainless steel. Under UV-Vis light illumination, the PANI-Ag-N-TiO2 coatings delivered a stable photocathodic potential of - 0.79 V, a much larger negative potential than was realized using PANI-N-TiO2(- 0.55 V) or PANI-TiO2 (- 0.40 V) coatings. The addition of Ag nanoparticles thus greatly enhanced the photo-cathodic response. Antimicrobial experiments demonstrated that the PANI-Ag-N-TiO2 coating offers good antibacterial activity (> 95% inhibition) againstE. coliunder UV-Vis light irradiation for 30 min, due to the generation of hydrogen peroxide or other reactive oxygen species capable of damaging the membrane ofE. colicells. Results suggest that PANI-Ag-N-TiO(2)composite coatings offer good antifouling performance in marine environments.