Facile Postsynthesis of Visible-Light-Sensitive Titanium Dioxide/Mesoporous SBA-15

Visible-light-sensitive titanium dioxide/mesoporous SBA-15 (TiO 2 /SBA-15) composites were synthesized through a postsynthetic approach with the assistance of ethylenediamine. The as-prepared nanocomposites were characterized by XRD, nitrogen adsorption, SEM, HRTEM/EDS, FT-IR, DR UV−vis, and XPS. TiO 2 nanoparticles are homogenously dispersed on the silica SBA-15. XPS analyses indicate that the oxygen atoms of TiO 2 were partially substituted by nitrogen atoms, resulting in good response to the visible-light absorption. Ethylenediamine plays a double role: (1) etching the surface of silica SBA-15 and directing its regeneration and (2) introducing nitrogen atoms to the lattice of TiO 2 . The excellent photocatalytic activity of the composites is evaluated via the photodecomposition of phenol in the liquid phase under visible- and ultraviolet-light illumination. The conversion of phenol varies with the content of TiO 2 in the composites, and the optimal value is up to 46.2% under illumination in the visible region.