Physics Section-MMV, Department of Physics, Banaras Hindu University, Varanasi 221005, India.
Department of Electronics Engineering, Indian Institute of Technology (BHU), Varanasi 221005, India.
J Phys Chem B. 2022 Jun 2;126(21):3931-3939. doi: 10.1021/acs.jpcb.2c00678. Epub 2022 May 18.
In the present study, an investigation of the electronic excitation energy transfer between two p-type fluorescent semiconductors, F8BT [poly(9,9-dioctylfluorene-alcohol-benzothiadiazole] and TIPS-P [6,13-bis(triisopropylsilylethynyl)pentacene], has been carried out in a chloroform solution using steady-state and time-domain fluorescence techniques. The spectral overlap integral between donor (F8BT) emission and acceptor (TIPS-P) absorption is 2.04 × 10 nm/(M cm), and the corresponding critical transfer distance is 53.12 Å. In donor decay dynamics, at the lower acceptor concentrations, the observed results deviate from the Förster theory due to the combined effect of diffusion and energy migration. However, it does not exhibit energy migration and distribution for higher acceptor concentrations, and the system follows the Förster model of resonance excitation energy transfer (FRET). The higher value of the donor-acceptor interaction strength than self-interaction (donor-donor interaction) appears to be responsible for this behavior. Further, in acceptor decay, the appearance of the rise time and its decrease with the acceptor concentration confirms FRET from F8BT to TIPS-P.
在本研究中，使用稳态和时域荧光技术，在氯仿溶液中研究了两种 p 型荧光半导体 F8BT（聚（9,9-二辛基芴醇-苯并噻二唑）和 TIPS-P[6,13-双（三异丙基硅基乙炔基）并五苯]之间的电子激发能量转移。供体（F8BT）发射和受体（TIPS-P）吸收之间的光谱重叠积分是 2.04×10 nm/（M cm），相应的临界转移距离是 53.12 Å。在供体衰减动力学中，在较低的受体浓度下，由于扩散和能量迁移的综合影响，观察到的结果偏离了Förster 理论。然而，在较高的受体浓度下，它没有表现出能量迁移和分布，并且该系统遵循共振激发能量转移（FRET）的 Förster 模型。与自相互作用（供体-供体相互作用）相比，供体-受体相互作用强度较高似乎是导致这种行为的原因。此外，在受体衰减中，上升时间的出现及其随受体浓度的降低证实了 F8BT 到 TIPS-P 的 FRET。
