Saha Samyabrata, Majhi Debashis, Bhattacharyya Kalishankar, Preeyanka Naupada, Datta Ayan, Sarkar Moloy
School of Chemical Sciences, National Institute of Science Education and Research, HBNI, Bhubaneswar, Khurda-752050, India.
Department of Spectroscopy, Indian Association for the Cultivation of Science, Kolkata 700032, India.
Phys Chem Chem Phys. 2018 Apr 4;20(14):9523-9535. doi: 10.1039/C7CP07233C.
With an aim to understand the intermolecular/particle interaction and the optical properties of the inorganic-organic hybrid nanostructured materials, Förster resonance energy transfer (FRET) between negatively charged CdS quantum dots (donor) and positively charged Oxazine 170 perchlorate (acceptor) has been investigated by employing steady-state and time-resolved fluorescence spectroscopy. Investigations revealed that size-dependent changes in the FRET efficiency of different QD-dye FRET pairs occurred mainly due to the electrostatic effects. Interestingly, the present study also reveals that at a higher concentration of dye molecules, aggregation occurs on the QD surface and the quenching of dye fluorescence occurs due to homo-FRET process. The homo-FRET process in this case has been established by exploiting steady-state fluorescence anisotropy measurements. The feasibility of aggregate formation and the homo-FRET interaction between the dye molecules has also been demonstrated through quantum mechanical calculations.
为了理解无机-有机杂化纳米结构材料的分子间/粒子相互作用及光学性质，通过稳态和时间分辨荧光光谱研究了带负电荷的硫化镉量子点（供体）与带正电荷的高氯酸氧杂蒽170（受体）之间的Förster共振能量转移（FRET）。研究表明，不同量子点-染料FRET对的FRET效率随尺寸的变化主要是由静电效应引起的。有趣的是，本研究还表明，在较高浓度的染料分子下，染料分子会在量子点表面发生聚集，并且由于同型FRET过程导致染料荧光猝灭。通过利用稳态荧光各向异性测量确定了这种情况下的同型FRET过程。还通过量子力学计算证明了染料分子聚集形成及同型FRET相互作用的可行性。
