Wang Yu, Wu Huang, Li Penghao, Chen Su, Jones Leighton O, Mosquera Martín A, Zhang Long, Cai Kang, Chen Hongliang, Chen Xiao-Yang, Stern Charlotte L, Wasielewski Michael R, Ratner Mark A, Schatz George C, Stoddart J Fraser
Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL, 60208, USA.
School of Chemistry, University of New South Wales, Sydney, NSW, 2052, Australia.
Nat Commun. 2020 Sep 15;11(1):4633. doi: 10.1038/s41467-020-18431-7.
Two-photon excited near-infrared fluorescence materials have garnered considerable attention because of their superior optical penetration, higher spatial resolution, and lower optical scattering compared with other optical materials. Herein, a convenient and efficient supramolecular approach is used to synthesize a two-photon excited near-infrared emissive co-crystalline material. A naphthalenediimide-based triangular macrocycle and coronene form selectively two co-crystals. The triangle-shaped co-crystal emits deep-red fluorescence, while the quadrangle-shaped co-crystal displays deep-red and near-infrared emission centered on 668 nm, which represents a 162 nm red-shift compared with its precursors. Benefiting from intermolecular charge transfer interactions, the two co-crystals possess higher calculated two-photon absorption cross-sections than those of their individual constituents. Their two-photon absorption bands reach into the NIR-II region of the electromagnetic spectrum. The quadrangle-shaped co-crystal constitutes a unique material that exhibits two-photon absorption and near-infrared emission simultaneously. This co-crystallization strategy holds considerable promise for the future design and synthesis of more advanced optical materials.
与其他光学材料相比，双光子激发近红外荧光材料因其卓越的光学穿透性、更高的空间分辨率和更低的光散射而备受关注。在此，一种简便高效的超分子方法被用于合成一种双光子激发近红外发光共晶材料。基于萘二亚胺的三角形大环与蒄选择性地形成了两种共晶体。三角形共晶体发出深红色荧光，而四边形共晶体则呈现以668nm为中心的深红色和近红外发射，与其前体相比红移了162nm。受益于分子间电荷转移相互作用，这两种共晶体比其各自的组分具有更高的计算双光子吸收截面。它们的双光子吸收带延伸到电磁光谱的近红外二区。四边形共晶体构成了一种独特的材料，能同时展现双光子吸收和近红外发射。这种共结晶策略对于未来设计和合成更先进的光学材料具有很大的前景。
