Regulation of clusterization-triggered phosphorescence from a non-conjugated amorphous polymer: a platform for colorful afterglow

Abstract

Ultralong and colorful clusterization-triggered phosphorescence (CTP) has been realized by changing polymerization conditions of polyacrylamides (PAMs). These materials have huge potential in the application of sensing, anti-counterfeiting and LEDs.

Effective Internal and External Modulation of Nontraditional Intrinsic Luminescence

“…[ 1,2 ] However, there is little knowledge on the rational modulation of nontraditional intrinsic luminescence (NTIL) in terms of emission color, efficiency, and phosphorescence, on account of the limited understanding of the emission mechanism and structure–property relationships. [ 3 ] Among nonconventional luminophores, nonconjugated polymers with electron‐rich moieties have been reported [ 3,4 ] and various mechanisms proposed. [ 3–5 ] However, because of their structural uncertainty, a definite structure–NTIL relationship is difficult to acquire, which also hampers the understanding of emissive mechanism.…”

“…[ 3 ] Among nonconventional luminophores, nonconjugated polymers with electron‐rich moieties have been reported [ 3,4 ] and various mechanisms proposed. [ 3–5 ] However, because of their structural uncertainty, a definite structure–NTIL relationship is difficult to acquire, which also hampers the understanding of emissive mechanism. Molecular nonconventional luminophores that possess crystal structures with explicit conformation, molecular packing, and intra/intermolecular interactions, are thus highly desired.…”

Efficient metal-free organic room temperature phosphors

“…16d ). 109 The strong URTP and green afterglow disappeared in the presence of vapours, and at the same time, NH 3 imparted a drastic emission quenching. The afterglow restoration achieved by thermal removal of NH 3 ensures an afterglow switch using NH 3 vapour and temperature.…”

“…In 2020, Ling and coworkers reported a colourful afterglow through regulation of clusterization-triggered RTP of non-conjugated amorphous polyacrylamide ( PAM ). 109 The emission features of these non-conjugated polymers containing carbonyl and amine groups depend on the aggregation, which can result in electronic interactions by n–π and π–π interactions. Furthermore, the clusterization of amides can form a rigid conformation of polymer chains, which is helpful to inhibit nonradiative decay of excitons and to stabilize the excited state through hydrogen bonding.…”

All‐Organic, Temporally Pure White Afterglow in Amorphous Films Using Complementary Blue and Greenish‐Yellow Ultralong Room Temperature Phosphors

“…[10][11][12] However, design of highly efficient organic URTP emitters under ambient conditions, still remains as a grand challenge due to its weak spin-orbit coupling efficiency and the nonradiative dissipation of triplets via vibrational and oxygen quenching, which limits the generation of long-lived triplet states. [13][14][15] Ambient afterglow phosphorescence has been achieved in organic molecules via the restriction of the molecular motions by the crystallization of phosphors [16] or by embedding the phosphors in amorphous polymer matrices [17][18][19] or in the cavities/ interlayer galleries of host molecules/ materials. [20][21] Very recently, new molecular designs and photophysical processes have also been proposed to achieve organic afterglow, such as donor-acceptor thermally activated delayed fluorescence (TADF) exciplexes, [21][22][23] and by the delayed sensitization of singlets via phosphorescence energy transfer process.…”