Rhodamine B Removal of TiO2@SiO2 Core-Shell Nanocomposites Coated to Buildings

Abstract

Surface application of photocatalyst in cement-based materials could endow it with photocatalytic properties, however, the weak adhesion between photocatalyst coatings and the substrates may result in poor durability in outdoor environments. In this study, TiO2@SiO2 core-shell nanocomposites with different coating thicknesses were synthesized by varying the experiment parameters. The results indicate that SiO2 coatings accelerated the rhodamine B removal to a certain extent, owing to its high surface area; however, more SiO2 coatings decreased its photocatalytic efficiencies. The cement matrix treated with TiO2@SiO2 core-shell nanocomposites showed good photocatalytic efficiency and durability after harsh weathering processing. A reaction mechanism was revealed by the reaction of TiO2@SiO2 nanocomposites with Ca(OH)2.