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A series of solid supramolecules based on acrylamide–phenylpyridium copolymers with various substituent groups (P−R: R=−CN, −CO2Et, −Me, −CF3) and cucurbit[7]uril (CB[7]) are constructed to exhibit tunable second‐level (from 0.9 s to 2.2 s) room‐temperature phosphorescence (RTP) in the amorphous state. Compared with other solid supramolecules P−R/CB[7] (R=−CN, −CO2Et, −Me), P−CF3/CB[7] displays the longest lifetime (2.2 s), which is probably attributed to the fluorophilic interaction of cucurbiturils leading to a uncommon host–guest interaction between 4‐phenylpyridium with −CF3 and CB[7]. Furthermore, the RTP solid supramolecular assembly (donors) can further react with organic dyes Eosin Y or SR101 (acceptors) to form ternary supramolecular systems featuring ultralong phosphorescence energy transfer (PpET) and visible delayed fluorescence (yellow for EY at 568 nm and red for SR101 at 620 nm). Significantly, the ultralong multicolor PpET supramolecular assembly can be further applied in fields of anti‐counterfeiting and information encryption and painting. [ABSTRACT FROM AUTHOR]

Developing red thermally activated delayed fluorescence (TADF) emitters, attainable for both high‐efficient red organic light‐emitting diodes (OLEDs) and non‐doped deep red/near‐infrared (NIR) OLEDs, is challenging. Now, two red emitters, BPPZ‐PXZ and mDPBPZ‐PXZ, with twisted donor–acceptor structures were designed and synthesized to study molecular design strategies of high‐efficiency red TADF emitters. BPPZ‐PXZ employs the strictest molecular restrictions to suppress energy loss and realizes red emission with a photoluminescence quantum yield (ΦPL) of 100±0.8 % and external quantum efficiency (EQE) of 25.2 % in a doped OLED. Its non‐doped OLED has an EQE of 2.5 % owing to unavoidable intermolecular π–π interactions. mDPBPZ‐PXZ releases two pyridine substituents from its fused acceptor moiety. Although mDPBPZ‐PXZ realizes a lower EQE of 21.7 % in the doped OLED, its non‐doped device shows a superior EQE of 5.2 % with a deep red/NIR emission at peak of 680 nm. [ABSTRACT FROM AUTHOR]

Sind gründlich studiert worden, allerdings verlief die Entwicklung von roten/nahinfraroten TADF-Emittern viel langsamer als die von grünen und blauen Emittern (TADF: thermisch aktivierte verzögerte Fluoreszenz). Sind gründlich studiert worden, allerdings verlief die Entwicklung von roten/nahinfraroten TADF-Emittern viel langsamer als die von grünen und blauen Emittern (TADF: thermisch aktivierte verzögerte Fluoreszenz). Zhang et al. präsentieren in ihrem Forschungsartikel auf S. 14808 zwei neuartige rote TADF-Emitter. [Extracted from the article]