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Herein, two kinds of amorphous solid‐state supramolecular systems with purely organic room temperature phosphorescence (RTP) from calix[3]phenothiazine (C[3]Pz) activated by 1,2‐/1,3‐dicyanobenzene (1,2‐/1,3‐DCB) are reported. Different from macrocycle‐confined guest phosphorescence emission, RTP of these two amorphous solid‐state supramolecular systems is entirely from the 1,2‐/1,3‐DCB rivets C[3]Pz cavity to form dense supramolecular complex through CH...π interactions, leading to two different phosphorescence emissions at 566/524 nm under 430 nm excitation, respectively. Although C[3]Pz shows a regular arrangement in the crystal, the vibration dissipation of the benzene ring results in C[3]Pz emitting only fluorescence at 508 nm at room temperature. 1,2‐DCB and 1,3‐DCB can act as molecular rivets to fix the C[3]Pz to inhibit molecular vibration so as to reduce nonradiative relaxation, which enables C[3]Pz to achieve effective RTP emission with 20.8–36.8% quantum yields. This kind of guest‐activated host RTP, which is fairly rare in supramolecular systems, is successfully used for color QR codes and information encryption. [ABSTRACT FROM AUTHOR]

Phosphorescent materials constructed by macrocyclic host confined guest has become a research hotspot in bioimaging. Herein, a highly efficient phosphorescent light‐harvesting supramolecular switch constructed by cucurbit[8]uril (CB[8]) encapsulated dicationic 6‐bromoisoquinoline derivative (G), sulfonatocalix[4]arene (SC4AD), near‐infrared (NIR) fluorescence dyes, and diarylethene molecular switch (1) is reported. First, the resulting supramolecular foldamer formed by G and CB[8] works as a phosphorescent donor with phosphorescence at 605 nm. When secondary assembling with SC4AD, the phosphorescent emission peak of G⊂CB[8] generates a hypsochromic shift to 583 nm with a 6.4‐fold enhancement of intensity. Further, NIR fluorescence dyes Nile Blue (NiB) and Sulfo‐Cyanine 5 (cy5) are introduced to the assembly as acceptors to construct phosphorescent light‐harvesting systems. As expected, light‐harvesting systems with energy transfer efficiency of 57.5%/75.7% and a high antenna effect of 359.7/247.7 are constructed at an efficient donor/acceptor ratio of 100:1/15:2 for NiB and cy5, respectively. After co‐assembly with diarylethene derivative (1), the phosphorescence transferred from G⊂CB[8]@SC4AD/NiB (or cy5) to 1 and caused the photoluminescence quenching after irradiation by 365 nm light. And the photoluminescence of the light‐harvesting system was restored with the irradiation by >450 nm light. The highly efficient phosphorescent light‐harvesting system is applied to lysosome targeted imaging in HeLa cells and information encryption. [ABSTRACT FROM AUTHOR]

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]

An enhancement strategy is realized for ultralong bright room‐temperature phosphorescence (RTP), involving polymerization between phosphor monomers and acrylamide and host–guest complexation interaction between phosphors and cucurbit[6,7,8]urils (CB[6,7,8]). The non‐phosphorescent monomers exhibit 2.46 s ultralong lifetime after copolymerizing with acrylamide. The improvement is due to the rich hydrogen bond and carbonyl within the polymers which promote intersystem crossing, suppress nonradiative relaxation and shield quenchers effectively. By tuning the ratio of chromophores, a series of phosphorescent copolymers with different lifetimes and quantum yields are prepared. The complexation of macrocyclic hosts CB[6,7,8] promote the RTP of polymers by blocking aggregation‐caused quenching, and offsetting the losses of aforementioned interaction provided by polymer. Multiple lifetime‐encoding for digit and character encryption are achieved by utilizing the difference of their lifetimes. [ABSTRACT FROM AUTHOR]