Abstract

The development of self-cleaning surfaces is crucial for reducing maintenance costs, conserving energy, and minimizing detergent use across various applications, including construction, healthcare, and consumer electronics. In this study, we introduce a novel glass surface with self-cleaning properties under visible light based on the photocatalytic activity of immobilized BiOI/TiO? heterostructures. The BiOI/TiO? heterostructures were synthesized, characterized, and immobilized on glass slides to evaluate their photocatalytic and self-cleaning efficiencies under simulated solar conditions. Among the synthesized heterostructures, the BiOI(0.1)/TiO?(0.9) heterostructure leverages an S-scheme charge transfer mechanism, significantly enhancing charge separation efficiency and hydroxyl radical generation under simulated solar conditions. This structure results in enhanced photocatalytic activity compared to pure TiO? and BiOI, as evidenced by improved methyl orange degradation and self-cleaning performance. Self-cleaning tests based on ISO 27,448:2009 showed that the glass surface with immobilized BiOI(0.1)/TiO?(0.9) significantly outperforms glass surfaces with immobilized nanoparticles of pure TiO? and pure BiOI, reducing water contact angles faster and enabling surface cleanliness with minimal irradiation. These findings highlight the BiOI(0.1)/TiO?(0.9) heterostructure as a high-efficiency photocatalyst with potential application in self-cleaning coating opening pathways for next-generation energy-efficient antimicrobial surfaces in real-world applications. © 2025