Surface derivatization of titanium dioxide nanoparticles with a Fe(III)-porphyrin has been carried out following a new procedure whereby the complex, rather than the surface, contains the aminopropylsilane functional group. Characterization of the light trasparent dispersions by laser flash photolysis, UV-vis spectroscopy and photoelectrochemical methods has shown that the nature of the solvent is an imporetant parameter in determining the redox processes involving the grafted porphyrin. The photocatalytic activity of the composite system was assessed in the process of monooxygenation of cyclohexane and cyclohexene by molecular oxygen
