Superhydrophobic photothermal coatings based on candle soot for prevention of biofilm formation

Bacterial biofilms formed on the material surfaces have posed a series of serious problems for human health and industries. The treatment of mature biofilms is particularly difficult because they are inher-ently highly resistant against antibiotics and other adverse factors. The prevention is strategically advan-tageous over the treatment, and thus the development of innovative surfaces with capability to inhibit biofilm formation is highly demanded. In this work, we developed a superhydrophobic photothermal coating for prevention of biofilm formation, which was based on candle soot with hierarchical structure and excellent light-to-heat conversion ability. This coating was fabricated by deposition of a candle soot layer on the substrate, followed by sequential chemical vapor deposition of tetraethoxysilane and immo-bilization of fluorinated silane to make the coating robust and superhydrophobic. The resulted coating could repel a majority of bacteria from the surface at the early stage, and then eradicate a small number of bacteria remained on the surface under a short-term irradiation of near-infrared laser. The combi-nation of anti-adhesive property and photothermal bactericidal property endowed the coating with good antibiofilm property to prevent biofilm formation for at least 2 weeks. This coating is facile for deposition on various substrates with good storage stability, showing great potential for diverse practical applications to solve the biofilm-associated problems of materials and devices. (c) 2022 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Automated summary

In this study, a superhydrophobic photothermal coating was developed to prevent biofilm formation. The coating demonstrated both anti-adhesive and photothermal bactericidal properties, and could be deposited on various substrates, showing great potential for diverse practical applications.