Influence of nano SiO2/Al2O3-TiO2 powder on strength and durability properties of concrete

This study investigates the application of titanium dioxide (TiO₂), a photocatalyst, to concrete by utilizing TiO₂-coated nano-SiO₂ (NSTP) and nano-Al₂O₃ (NATP) substrates. The incorporation of NSTP and NATP into concrete enhanced mechanical properties through pozzolanic reactions, generating calcium silicate hydrate (C-S-H) and calcium aluminate hydrate (C-A-H) gels that densified the matrix and reduced voids. Concrete containing NSTP and NATP exhibited higher compressive strength compared to conventional TiO₂-based concrete, as well as improved durability, including resistance to chemical attack, carbonation, and chloride ion penetration. Furthermore, under ultraviolet light (<380 nm), NSTP and NATP based concrete demonstrated 100–110% higher photocatalytic efficiency in nitrogen oxide decomposition compared to commercial TiO 2 based systems. These improvements are attributed to enhanced hydration product polymerization and optimized nanoparticle dispersion within the concrete matrix. The findings suggest that NSTP and NATP based concrete can serve as a multifunctional material for sustainable infrastructure by improving structural performance and environmental remediation such as nitrogen oxide decomposition reactions.