Facile One-Step Synthesis of Inorganic-Framework Molecularly Imprinted TiO₂ and Its Molecular Recognitive Photocatalytic Degradation of Target Pollutant

Inorganic-framework molecularly imprinted TiO₂ with molecular recognitive photocatalytic activity was prepared by a facile one-step method using tetrabutyl orthotitanate as titanium source as well as the precursor of functional monomer. Unlike the approach of coating an organic layer of molecularly imprinted polymer on TiO₂, the adopted method for the synthesis of molecularly imprinted TiO₂ nanoparticles that are molecular recognitive for the degradation of a target pollutant is simple and direct. Compared to non-imprinted TiO₂, the molecularly imprinted TiO₂ shows higher adsorption capacity and molecular recognition towards the template molecules. The photocatalytic activity of molecularly imprinted TiO₂ towards the target molecules is more than two times that of non-imprinted TiO₂, a result of selective adsorption of target molecules on molecularly imprinted TiO₂. The enhancement in terms of adsorption capacity and molecular recognition can be attributed to the chemical interaction between the target molecules and imprinted cavities, as well as to the geometric matching between imprinted cavities and target molecules. Moreover, the molecularly imprinted TiO₂ exhibits excellent regeneration ability.