Long-Term Antimicrobial Durability of Visible-Light Photocatalytic Coatings for Indoor Environmental Surfaces
DOI:
https://doi.org/10.11113/jomalisc.v5.114Keywords:
visible light active, photocatalyst, long-term antimicrobial coating, spray coating, indoor environmentAbstract
Microbial contamination of indoor environmental surfaces contributes to the transmission of infectious diseases and poses ongoing challenges for maintaining hygienic indoor environments. Conventional disinfectants typically provide only temporary antimicrobial effects and require repeated application, while some technologies such as ultraviolet irradiation may introduce safety or operational limitations. Therefore, durable antimicrobial surface technologies capable of continuous microbial inactivation under indoor lighting conditions are highly desirable. In this study, a visible-light responsive photocatalytic coating was developed for long-term antimicrobial protection of indoor surfaces. The coating formulation consists of a photocatalyst, a photosensitizer, and a functional binder designed to sustain photocatalytic activity under typical indoor illumination. The dispersion exhibited a particle size of 196.2 nm, zeta potential of 10.9 mV, surface tension of 33.20 mN m⁻¹, and low viscosity suitable for coating applications. The prepared sample was spray coating on the wall of a salon. Long-term field monitoring using ATP bioluminescence measurements showed that coated surfaces maintained relative light unit (RLU) values well below the hygiene benchmark of 1500 over a period of up to 48 months. These results demonstrate the potential of visible-light photocatalytic coatings as durable antimicrobial solutions for improving indoor environmental hygiene.
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