Barman Debasish, Annadhasan Mari, Bidkar Anil Parsram, Rajamalli Pachaiyappan, Barman Debika, Ghosh Siddhartha Sankar, Chandrasekar Rajadurai, Iyer Parameswar Krishnan
Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati, 781039, India.
School of Chemistry, and Centre for Nanotechnology University of Hyderabad, Gachibowli, Prof. C. R. Rao Road, Hyderabad, 500046, India.
Nat Commun. 2023 Oct 20;14(1):6648. doi: 10.1038/s41467-023-42017-8.
Photofunctional co-crystal engineering strategies based on donor-acceptor π-conjugated system facilitates expedient molecular packing, consistent morphology, and switchable optical properties, conferring synergic 'structure-property relationship' for optoelectronic and biological functions. In this work, a series of organic co-crystals were formulated using a twisted aromatic hydrocarbon (TAH) donor and three diverse planar acceptors, resulting in color-tunable solid and aggregated state emission via variable packing and through-space charge-transfer interactions. While, adjusting the strength of acceptors, a structural transformation into hybrid stacking modes ultimately results in color-specific polymorphs, a configurational cis-isomer with very high photoluminescence quantum yield. The cis-isomeric co-crystal exhibits triplet-harvesting thermally activated delayed fluorescence (TADF) characteristics, presenting a key discovery in hydrocarbon-based multicomponent systems. Further, 1D-microrod-shaped co-crystal acts as an efficient photon-transducing optical waveguides, and their excellent dispersibility in water endows efficient cellular internalization with bright cell imaging performances. These salient approaches may open more avenues for the design and applications of TAH based co-crystals.
基于供体-受体π共轭体系的光功能共晶工程策略有助于实现便捷的分子堆积、一致的形态以及可切换的光学性质，为光电和生物学功能赋予协同的“结构-性质关系”。在这项工作中，使用扭曲芳烃（TAH）供体和三种不同的平面受体制备了一系列有机共晶，通过可变堆积和空间电荷转移相互作用实现了颜色可调的固态和聚集态发射。同时，调节受体的强度，结构转变为混合堆积模式最终导致颜色特异性多晶型物，即具有非常高光致发光量子产率的构型顺式异构体。顺式异构共晶表现出三重态捕获热激活延迟荧光（TADF）特性，这是基于烃的多组分体系中的一项关键发现。此外，一维微棒状共晶充当高效的光子转导光波导，它们在水中的优异分散性赋予了高效的细胞内化以及明亮的细胞成像性能。这些显著的方法可能为基于TAH的共晶的设计和应用开辟更多途径。
