Compared with fluorescent materials, metal-free organic environmental afterglow materials, with larger Stokes shifts, longer lifetimes, higher S/N ratios, and sensitivities, present potential in new applications. However, achieving air stability and long lifetime organic afterglow systems with tunable emission color still remains a challenge. Herein, we have designed and synthesized luminescent copolymers exhibiting afterglow emission with tunability including white-light afterglow with considerable quantum yield [Commission Internationale de l'Eclairage (CIE) coordinates (0.32, 0.33), Φ P = 11%] in the amorphous state through the rarely reported triplet-to-singlet Förster resonance energy transfer (TS-FET). Also, they can emit different colors under UV light, including white-light [CIE coordinates (0.31, 0.33), Φ Pl = 27%]. This strategy was achieved by copolymerizing two simple-structured single-benzene-based compounds with acrylamide (AM) in different ratios. In addition, these materials can also be employed as a safety ink for paper paving the way for long lifetime luminescent material applications.

Crystal engineering is employed widely in developing metal-free room-temperature phosphorescence (RTP) materials, but the weak responsiveness in rigid state and poor selectivity during crystallization limit the research of RTP materials with specific recognition properties. Herein, based on multicomponent crystallization and the deformation of phosphor, we have developed a galactose-functionalized polyhydric compound (BHB) with a twisted 4-bromobiphenyl structure, to realize methanol selectively activated "off-on" RTP system. Methanol molecules selectively formed solvate with BHB and rigidified the crystal structure by enriching intermolecular noncovalent interactions. Meanwhile, the distortion of the biphenyl group facilitated the intersystem crossing process effectively, alongside the heavy-atom effect from the bromo substitute, thereby, activating the RTP of BHB. Thus our current research approach realizes RTP materials with selective recognition function by controlling multiple noncovalent interactions such as hydrogen and halogen bonding of molecular systems with structurally distorted phosphors.

A novel supermolecular self-assembly based on ternary host-guest interaction between cucurbit[8]uril (CB transmission electron microscopy (TEM) and dynamic light scattering (DLS) measurements. Meanwhile, the supramolecular polymerization could promote the conversion of the azobenzene from cis to trans, which ultimately results in no isomerism upon UV irradiation.

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Amorphous organic room-temperature phosphorescent (RTP) materials are promising for their facile preparation and processability, while the conformation effects of phosphors at amorphous state are lack of study in comparison with the rigid effects due to the commonly irregular assembling and dispersal of phosphors in rigid systems. Herein, we report a series of phosphorescent molecules modified by polyhydroxy galactose, whose RTP emission at the amorphous state can be regulated by controlling the conformational distortion of the phosphorescent segments. Further, a strong RTP emission is facilely obtained by the co-assembling between polyhydroxy phosphors and polyhydroxy matrices (α-CD, β-CD, and chitosan). Owing to the rigid effect of the enhanced hydrogen bonding cross-linking, the highest RTP quantum yield reaches 19.4%; whereas, the RTP emissions of assemblies become conformation insensitive. The conflicting relationship between the conformation effect and rigid effect is attributed to the differences between aggregated single-component systems and dispersed assembling systems. Besides, the unique and different moisture responsiveness of the co-assembling samples is discovered and further applied in data encryption. The research expands the scope for designing amorphous pure organic RTP materials with supramolecular strategies and shows a modularized approach for assembling-enhanced phosphorescence.