Abstract: | 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 functionalized π‐conjugated oligomers to form heterosupramolecular assemblies. When [2,2′;5′,2″]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. |