Controlled photocatalytic ability of titanium dioxide particle by coating with nanoporous silica

We have successfully deposited nanoporous silica layers on titania nanoparticles, commercial P25 (Degussa), by the reaction of P25 with aqueous mixture of TEOS (silica source) and CTA (porogen) and the subsequent calcination. The thickness of nanoporous silica layer was controlled by changing the added amount of TEOS.