Four strategies towards customized rainbow/white light emission from a series of organic charge-transfer cocrystals and their heterostructures

Abstract

A series of structurally isomorphic charge-transfer cocrystals with 1,2,4,5-tetracyanobenzene as the electron acceptor were presented in this contribution to highlight four strategies towards tunable rainbow/white light emission in crystals, i.e.,...

Synthesis and photophysical properties of charge transfer cocrystals based on TCNB and fluorene and its derivatives

“…Recently organic cocrystals have been widely studied due to their unique and novel properties, such as tunable luminescence, 1,2 two-photon absorption, 3,4 optical waveguide, 5–7 bipolar charge transport, 8,9 photothermal conversion, 10–12 etc. Organic cocrystals are single-phase materials assembled by two or more molecules according to a certain stoichiometric ratio.…”

Precise Synthesis of Organic Cocrystal Alloys with Full‐Spectrum Emission Characteristics for the Stepless Color Changing Display

“…Organic light-emitting semiconductor materials have been extensively studied because of their excellent luminescence properties, especially aromatic organic molecules as CT cocrystals of donors, [1][2][3][4][5][6] which has been commonly used in organic light-emitting diode (OLED), [7,8] optical [9,10] waveguides, [11][12][13] and 2D photon codes, [14,15] biomedical, [16][17][18][19] and other fields. A series of factors, such as the size of molecules, crystal morphology, steric hindrance, and intermolecular interaction, would result in diverse molecular-packing structures [47,48] and affect the recognition and co-assembly of donor and acceptor molecules. Thus, the luminous color of organic luminescent materials can be adjusted, which is particularly important for its application.…”

COF@COF: Constructing Core–Shell Structured Covalent–Organic Frameworks from Interpenetration Isomers

“…The construction of COF@COF from the point of view of structure design remains out of reach. We have been obsessed with developing new methods for establishing hierarchies in various material systems and have proposed a concept of “homologous hierarchical structure” resolving difficulties of heterogeneous outgrowth methods between different metal–organic framework species. ,,, In this work, a similar but new concept was developed for COF@COF that uses “homologous” COF pieces, i.e., species with identical framework structures to build different hierarchies, which can easily circumvent the problem of lattice mismatch between different COFs. For a proof-of-concept, the classical three-dimensional covalent–organic framework COF-300 has been chosen as the model system for the following reasons: (1) COF-300 has two interpenetrating isomers, , the 5-fold interpenetrating COF-300 (dia-c5 COF-300) and the 7-fold interpenetrating COF-300 (dia-c7 COF-300), both of which have the same diamond cubic framework structure while differing in the degree of interpenetration.…”