Purely Organic Blue Room‐Temperature Phosphorescence Activated by Acrylamide In Situ Photopolymerization

Abstract

Purely organic room‐temperature phosphorescence (RTP), especially blue phosphorescence, has aroused considerable attention in organic optoelectronic applications. Herein, a purely solid supramolecular assembly with blue phosphorescence is constructed by 6‐bromoisoquinoline‐modified β‐cyclodextrin (CD‐IQ), acrylamide (AAm), and cucurbit[7]uril (CB[7]) based on in situ photopolymerization strategy, accompanied by blue RTP emission at 450 nm. The abundant hydrogen‐bonding network between the formed polyacrylamide matrix and the β‐CD effectively restricts the motion of the 6‐bromoisoquinoline chromophore and suppresses the nonradiative transition, realizing purely blue RTP emission. As compared with CD‐IQ‐polymer, supramolecular assembly between CB[7] and CD‐IQ can improve the quantum yield and lifetime from the initial 25.5% and 238.47 ms to 49.41% and 268.9 ms, respectively, which is attributed to the confinement effect of the cucurbituril hydrophobic cavity, and can be further applied in fields of anti‐counterfeiting, information encryption, and writing.

Smart organic materials based on macrocycle hosts

“…Taking advantage of the rigid environment and the inhibition of the molecular motions offered by the polymer matrixes, RTP materials based on the crosslinking of supramolecular polymers have been achieved assisted by the host-guest interactions of CD and CB[n]. 34,35 In particular, a type of ''supramolecular pins'' with efficient phosphorescence in both solutions and solid phases was developed by Liu and coworkers following ''one host with one guest'' binding mode between CB [8] and phenylpyridinium salt, of which the afterglow was substantially promoted by further incorporation into polymer matrixes with high phosphorescence efficiency (Fig. 3b).…”

Recent advances in the design of afterglow materials: mechanisms, structural regulation strategies and applications

“…349 Increasingly, CB[n] supramolecularly assembled RTP materials with excellent properties are being discovered. [350][351][352] Ma et al constructed host-guest RTP materials that controlled the location of CB[n] on guest molecules by adjusting the pH, thereby changing the intensity of the phosphorescent signals. 353 Liu et al selected organic salts as guest molecules, which greatly improved the PQY of the complex to 81.2%, which at the time was the record PQY for a pure organic system.…”

Circularly Polarized Room-Temperature Phosphorescence with an Ultrahigh Dissymmetry Factor from Carbonized Polymer Dots by Stacked Chiral Photonic Films

“…Various types of novel CPL-featured materials, including fluorescence − and thermally activated delayed fluorescence, , have been designed and fabricated. Recently, the development of room temperature phosphorescence (RTP) materials has received great attention in the past few years because of their unique long afterglow characteristics and wide range of applications in sensors, − bioimaging, , information encryption, and anti-counterfeiting. − Although phosphorescent materials have made great progress in achieving long lifetimes and high quantum yields (QYs), , novel RTP materials with CPL properties are still rarely investigated.…”