Color‐Tunable Supramolecular Luminescent Materials

Abstract

Constructing multicolor photoluminescent materials with tunable properties is an attractive research objective on account of their abundant applications in materials science and biomedical engineering. By comparison with covalent synthesis, supramolecular chemistry has provided a more competitive and promising strategy for the production of organic materials and the regulation of their photophysical properties. By taking advantage of dynamic and reversible noncovalent bonding interactions, supramolecular strategies can, not only simplify the design and fabrication of organic materials, but can also endow them with dynamic reversibility and stimuli responsiveness, making it much easier to adjust the superstructures and properties of the materials. Occasionally, it is possible to introduce emergent properties into these materials, which are absent in their precursor compounds, broadening their potential applications. In an attempt to highlight the state‐of‐the‐art noncovalent strategies available for the construction of smart luminescent materials, an overview of color‐tunable materials is presented in this Review, with the emphasis being placed on the examples drawn from host–guest complexes, supramolecular assemblies and crystalline materials. The noncovalent synthesis of room‐temperature phosphorescent materials and the modulation of their luminescent properties are also described. Finally, future directions and scientific challenges in the emergent field of color‐tunable supramolecular emissive materials are discussed.

Recent Advances in Mechanochromism of Metal-Organic Compounds

“…Luminescent materials have always been valued by researchers due to their widely use in data storage, optoelectronic devices, biological imaging and other fields (Zhu et al, 2016;Shi et al, 2018;Wang et al, 2021;Jackson et al, 2021;Yin et al, 2021;Min et al, 2022). Metal-organic compounds (MOC), composed of metal ions and organic ligands, are expected to exhibit more interesting photophysical properties.…”

Dynamic Timing Control over Multicolor Molecular Emission by Temporal Chemical Locking

“…Chemical control over molecular luminescent properties not only facilitates the fundamental understanding of molecular photophysics, [1] but also provides tremendous opportunities towards diverse applications [2] such as imaging, sensors, anti-counterfeiting and optical displays. [3][4][5] During the past decades, remarkable efforts have been made on the precise control of molecular luminescence, [6][7][8][9] including fluorescence and phosphorescence, by elaborating molecular structures and supramolecular assembling manners.…”

“…[10][11][12] Meanwhile, introducing stimuli-responsive structural units into molecular emissive systems offers many approaches to modulating (supra)molecular emission in a dynamic and reversible manner, enabling the emergence of a class of smart luminescent materials. [2,3,10,13,14] Current systems mostly focus on the stimuli-controlled emission switching among different thermodynamically stable states, i.e. fluorescent molecular switches.…”

“…[28] These efforts have exhibited the versatility and uniqueness of DPAC fluorophores as a candidate for fabricating single-fluorophore multi-color systems. [2] Motivated by these research bases, we envisioned that the DPAC unit could serve as an ideal model for fabricating smart emissive system.…”

A Calix[3]acridan‐Based Host–Guest Cocrystal Exhibiting Efficient Thermally Activated Delayed Fluorescence

“…[10] By virtue of noncovalent interactions between the host and guest, the complexes may exhibit enhanced or emergent photophysical properties in comparison with their constituent components. [11] Besides, the host-guest complex is an ideal system to obtain intermolecular CT state as well, in which the arrangement between the donor and acceptor can be well organized through the host-guest interactions. However, the host-guest charge transfer complexes displaying intense fluorescence were scarcely reported because the charge transfer between the host and guest usually quenches the fluorescence upon complex formation.…”