Centro de Física de Materiales (MPC, CSIC-UPV/EHU), Donostia International Physics Center (DIPC), Po Manuel de Lardizabal 5, Donostia-San Sebastian 20018, Spain.
Nanoscale. 2013 Oct 7;5(19):9317-23. doi: 10.1039/c3nr03016d. Epub 2013 Aug 16.
Hybrid materials formed by semiconductor quantum dots and J-aggregates of cyanine dyes provide a unique combination of enhanced absorption in inorganic constituents with large oscillator strength and extremely narrow exciton bands of the organic component. The optical properties of dendrite structures with fractal dimension 1.7-1.8, formed from J-aggregates integrated with CdTe quantum dots (QDs), have been investigated by photoluminescence spectroscopy and fluorescence lifetime imaging microscopy. Our results demonstrate that (i) J-aggregates are coupled to QDs by Förster-type resonant energy transfer and (ii) there are energy fluxes from the periphery to the centre of the structure, where the QD density is higher than in the periphery of the dendrite. Such an anisotropic energy transport can be only observed when dendrites are formed from QDs integrated with J-aggregates. These QD/J-aggregate hybrid systems can have applications in light harvesting systems and optical sensors with extended absorption spectra.
由半导体量子点和菁染料 J-聚集体形成的杂化材料提供了无机成分中增强的吸收与有机成分中大的振子强度和极窄激子带的独特组合。通过光致发光光谱和荧光寿命成像显微镜研究了由与 CdTe 量子点 (QD) 集成的 J-聚集体形成的分形维数为 1.7-1.8 的树枝状结构的光学性质。我们的结果表明：(i) J-聚集体通过Förster 型共振能量转移与 QD 偶联；(ii) 存在从结构外围到中心的能量流，其中 QD 的密度高于树枝状结构的外围。只有当树枝状结构由与 J-聚集体集成的 QD 形成时，才能观察到这种各向异性的能量传输。这些 QD/J-聚集体杂化系统可应用于具有扩展吸收光谱的光收集系统和光学传感器。
