A low-cost procedure for the preparation of mesoporous layers of TiO2 efficient in the environmental clean-up

We have developed a low-cost procedure for the deposition of mesoporous films of TiO2, which is easy to use and applicable for objects of various shape and size. This technique is based on spraying a sol containing titanium alkoxide, HCl, a suitable block-copolymer serving as a structure directing agent, and a solvent. Both the viscosity of the sol and the spraying conditions were precisely adjusted in order to achieve uniform coverage of the surface. The thickness of the films can be readily controlled by varying the number of deposited layers, their porosity being homogeneous and their surface area and pore volume increasing practically linearly with the increasing number of deposited layers. The mesoporous films of TiO2 are suitable photocatalysts for the oxidation of NO and the removal of liquid layers deposited on their surface. The effect of the flow rate of the gaseous mixture through the reactor on the photocatalytic conversion of NO was analyzed.