Adsorption on the TiO2 polymorphs: a molecular modeling study of topology effects on a photocatalytic "Minisci reaction"

Photocatalysis in organic synthesis concerns the use of light to induce chemical reactions onto organic substrates that are transparent in the wavelength range employed. The TiO2 photocatalysis may offer an alternative to thermal free-radical functionalization of heteroaromatic bases in the presence of classic metal-peroxide systems. Here we report a modeling study with Molecular Mechanics and Molecular Dynamics methods of the nanostructure effect of the TiO2 polymorphs on the adsorption of a heteroaromatic base (quinoline) and on the product of photocatalysis. The modeling studies can characterize the quinoline film formation on the TiO2 polymorphs surfaces on terms of the surface coverage, the interaction geometry at the interface and the interaction strength. These results show that MD methods yield useful information about the different film adsorption on the specific surfaces and on the substrate geomtery in the photocatalytic process.