Energy Transfer in Hybrid Organic/Inorganic Semiconductor Nanostructures

We report on direct formation of J-aggregates in cyanine dye solution by injection of colloidal CdTe quantum dots. The optical properties of formed J-aggregates have been investigated by absorption and photoluminescence spectroscopy and fluorescence lifetime imaging microscopy. Quantum dots/J-aggregate system shows the enhanced absorption in visible and ultraviolet parts of the spectrum typical of quantum dots, along with the narrow emission linewidth and fast recombination rate characteristic of the J-band emitters. Our studies suggest electrostatic association between the J-aggregates and quantum dots, followed by highly efficient energy transfer.