Advanced Functional Materials, Vol.12, No.8, 519-525, 2002
Photoinduced electron transfer in heterosupramolecular assemblies of TiO2 nanoparticles and terthiophene carboxylic acid in apolar solvents
Monodisperse stearic acid coated titanium dioxide nanoparticles (<3 nm) have been prepared and characterized. The nanoparticles are soluble in common apolar organic solvents and bind to carboxylic acid functionized π-conjugated oligomers to form heterosupramolecular assemblies. When [2,3';5',2&DPRIME;]terthiophene-5-carboxylic acid was coupled to the nanoparticles the fluorescence of the terthiophene moiety of the heterosupramolecular system was completely quenched due to a photoinduced electron transfer from terthiophene to titanium dioxide. Time-resolved fluorescence and Stern-Volmer analysis revealed that the quenching is predominantly static rather than dynamic and occurs in apolar solvents.