Nanotube Template-Directed Formation of Strongly Coupled Dye Aggregates with Tunable Exciton Fluorescence Controlled by Switching between J- and H-Type Electronic Coupling
Nanotube Template-Directed Formation of Strongly Coupled Dye Aggregates with Tunable Exciton Fluorescence Controlled by Switching between J- and H-Type Electronic Coupling
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DOI：
10.1021/acs.jpcb.1c02750
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发表时间：
2021-07-01
影响因子：
3.3
通讯作者：
Mandal, Sarthak
中科院分区：
文献类型：
--
作者：
Kamalakshan, Adithya;Ansilda, Roselin;Mandal, Sarthak
具有定制激子特性的强耦合染料聚集体可能会在开发人工光捕获和光电器件中得到应用。在这里，我们报告了使用石胆酸（LCA）作为模板，通过可调谐激子荧光来控制管状假异花青（PIC）染料J-和H-聚集体的形成。以较高LCA/PIC摩尔比（>= 5:1）形成的LCA模板PIC J聚集纳米管表现出尖锐的红移吸收带（555 nm）、强烈的荧光（565 nm）和较短的寿命（200 ps），所有这些都表明它们具有很强的超辐射特性。相比之下，以较低的 LCA/PIC 摩尔比 (2:1) 形成的 H 聚集体纳米管表现出显着的蓝移吸收带（在 420 nm 处）和高度红移的荧光发射（在 600 nm 处），并具有更长的寿命（4.40 ns）。通过控制LCA/PIC摩尔比实现PIC染料聚集体光学性质的受控切换可以作为有机光功能材料设计的重要指导。
Strongly coupled dye aggregates with tailored exciton properties may find their use in developing artificial light-harvesting and optoelectronic devices. Here, we report the control of tubular pseudoisocyanine (PIC) dye J- and H-aggregate formation with tunable exciton fluorescence using lithocholic acid (LCA) as a template. The LCA-templated PIC J-aggregate nanotubes formed at a higher LCA/PIC molar ratio (>= 5:1) exhibit a sharp, red-shifted absorption band (at 555 nm), intense fluorescence (at 565 nm), and shorter lifetime (200 ps), all indicating their strong superradiance properties. In contrast, the H-aggregate nanotubes formed at a lower LCA/PIC molar ratio (2:1) exhibit a significantly blue-shifted absorption band (at 420 nm) and highly red-shifted fluorescence emission (at 600 nm) with enhanced lifetime (4.40 ns). The controlled switching of the optical properties of the PIC dye aggregates achieved by controlling the LCA/PIC molar ratio could serve as an important guideline for the design of organic photo-functional materials.