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0D Hybrid Zn/Cd Halied for Color-Time-Dual-Resolved Security Applications: We devise a family of zero-dimensional (0D) hybrid metal halides based RTP materials with dual phosphorescence performance and adjustable lifetime scale, which realize color-lifetime-dual-resolved encoding ability, showcasing potential applications in multilevel anti-counterfeiting and information security. [Display omitted] • A new optical multiplexing concept of simultaneously utilizing the varied emission color and lifetime as dual temporary codes was proposed. • A new family of zero-dimensional (0D) organic metal halides was directly synthesized accompanied by tailorable lifetime at the same molecular platform. • High-security anti-Counterfeiting and 4D information encryption-decryption were demonstrated. Luminescent materials with engineered optical properties play an important role in anti-counterfeiting and information security technology. However, conventional luminescent coding is limited by fluorescence color or intensity, and high-level multi-dimensional luminescent encryption technology remains a critically challenging goal in different scenarios. To improve the encoding capacity, we present an optical multiplexing concept by synchronously manipulating the emission color and decay lifetimes of room-temperature phosphorescence materials at molecular level. Herein, we devise a family of zero-dimensional (0D) hybrid metal halides by combining organic phosphonium cations and metal halide tetrahedral anions as independent luminescent centers, which display blue phosphorescence and green persistent afterglow with the highest quantum yields of 39.9 % and 57.3 %, respectively. Significantly, the luminescence lifetime can be fine-tuned in the range of 0.0968–0.5046 μs and 33.46–125.61 ms as temporary time coding through precisely controlling the heavy atomic effect and inter-molecular interactions. As a consequence, synchronous blue phosphorescence and green afterglow are integrated into one 0D halide platform with adjustable emission lifetime acting as color- and time-resolved dual RTP materials, which realize the multiple applications in high-level anti-counterfeiting and information storage. The color-lifetime-dual-resolved encoding ability greatly broadens the scope of luminescent halide materials for optical multiplexing applications. [ABSTRACT FROM AUTHOR]

The charge‐transfer (CT) complexes with significant electron delocalization demonstrate abundant appealing physicochemical features and unique orbital hybridization, creating great promise as artificial light‐harvesting antennas for advanced optoelectronics, such as high‐performance organic room‐temperature phosphorescence (RTP). Herein, originally, a localized CT complex is proposed in organic microcrystals for exceptional orange‐emissive RTP with photoluminescence peaks at 575 and 625 nm based on the light‐harvesting antennas of CT states in organic microcrystals with donor doping. The localized CT state antennas can capture more singlet excitons, and transition them into triplet excitons, efficiently promoting intersystem crossing (ISC). Owing to the dense packing structure and strong CT interaction, the generation and stabilization of triplet excitons under ambient conditions are facilitated, imparting effective RTP with a lasting afterglow of up to 3 s. The controlled intensity ratio of fluorescence and phosphorescence is successfully achieved via finely adjusting the donor doping ratio, presenting a tunable CIE evolution from (0.42, 0.30) to (0.25, 0.12). The potential applications of these light‐harvesting microcrystals in information encryption and flexographic printing are illustrated. [ABSTRACT FROM AUTHOR]

The exploration of circularly polarized luminescence is important for advancing display and lighting technologies. Herein, by utilizing isomeric molecular engineering, a novel series of chiral molecules are designed to exploit both thermally activated delayed fluorescence (TADF) and room‐temperature phosphorescence (RTP) mechanisms for efficient luminescence. The cooperation of a small singlet‐triplet energy gap, moderate spin‐orbital coupling (SOC), and large oscillator strength enables efficient TADF emission, with photoluminescence quantum yields exceeding 90 %. By altering the symmetry of molecular structures, it is demonstrated that the intrinsic electronic SOC and vibrational SOC effects can be greatly enhanced to facilitate RTP emission. Notably, through modulating simultaneous TADF and RTP emissions, single‐molecule white emission is successfully achieved. Accordingly, the TADF‐based organic light‐emitting diode (OLED) achieves a maximum external quantum efficiency up to 30 %, representing exceptional performance of non‐aromatic amine‐based emitters. Furthermore, the first single‐molecule white OLED based on TADF and RTP dual‐emissive chiral material is developed, establishing a benchmark for the development of advanced display and lighting technologies. [ABSTRACT FROM AUTHOR]

The development of organic afterglow materials has garnered significant attention due to their diverse applications in smart devices, optoelectronics, and bioimaging. However, polymeric afterglow materials often suffer from short emission lifetimes, typically ranging from milliseconds to seconds, posing a significant challenge for achieving hour‐long afterglow (HLA) polymers. This study presents the successful fabrication of transparent HLA polymers by introducing electron donor/acceptor exciplexes. Employing aromatic polyesters as the polymer electron acceptor and charge reservoirs, the resulting HLA polymers exhibited a remarkable green afterglow that persisted for 12 hours under ambient conditions, representing the longest duration achieved for polymeric afterglow materials to date. Intriguingly, these HLA polymers could be activated solely by sunlight, maintaining a green afterglow for over 6 hours at room temperature in air, which outperformed all previously reported afterglow polymers. The doped polymers exhibited superior flexibility and transparency, making them ideal candidates for flexible display applications. Furthermore, successfully spinning these doped polymers into fibers while retaining their HLA properties opens up exciting possibilities for their use in wearable smart devices. [ABSTRACT FROM AUTHOR]

Developing smart materials with tunable high‐temperature afterglow (HTA) luminescence remains a formidable challenge. This study presents a metal‐free doping system using boric acid as matrix and polycyclic aromatic hydrocarbons as dopants. This composition achieves dynamically tunable afterglow combining a bright blue HTA lasting for over ten seconds even at 150 °C and an ultra‐long yellow room‐temperature phosphorescence below 110 °C. The observed HTA is attributed to the thermally released exciton recombination within the dopant molecules, which shows excellent temperature tolerance compared to traditional triplet related phosphorescence and thermally activated delayed fluorescence. The planarity of dopants is extensively investigated playing a pivotal role in modulating Dexter electron transfer (ET) for capturing released electrons and thereby affecting the overall performance of tunable HTA. This work provides an efficient and universal doping strategy to engineer tunable HTA through the synergistic action of thermally releasing electrons, Dexter ET and exciton recombination. [ABSTRACT FROM AUTHOR]

Room temperature phosphorescent (RTP) probes have significant advantages in the field of cellular imaging, as their long lifetimes can prevent interference from the spontaneous fluorescence of organisms. Persulfurated arenes are a typical RTP molecular parent nucleus. However, most of the applied research on them is concentrated in anti‐counterfeiting, and relatively few are applied in bioimaging. The molecular structure and structure‐property relationship of them applied in bioimaging are still in the exploration stage. In this work, we have designed and synthesized a series of RTP probes with long alkyl chains, all of which can be targeted to mitochondria with good water solubility for mitochondria‐targeted imaging. Further, we investigated the effect of alkyl chains on the luminescence properties of these probes, and found that the moderate length of alkyl chains can realize the enhancement of phosphorescence intensity. We believe this finding is of guiding significance for the design of molecular structures in the field of RTP probes. [ABSTRACT FROM AUTHOR]

Materials with room‐temperature phosphorescence (RTP) from deep red to near‐infrared (NIR) region exhibit great potential for emerging applications. However, such molecules typically require a low‐lying first triplet (T1) excited state, which may not be optimal for exciton stabilization, potentially compromising the phosphorescence lifetime. This study reports the design of four 9H‐carbazole (Cz) analogs with extended conjugation lengths used as dopants to achieve RTP emissions in deep red and NIR regions with lifetimes exceeding 700 ms. These findings reveal that substituting reactive hydrogen atoms in Cz analogs with methyl groups significantly enhances the photoluminescence quantum yield (PLQY) of these materials compared to their non‐methylated counterparts. Additionally, these doping systems can be activated by visible light, achieving persistent phosphorescence even under the excitation of 450 nm light. Theoretical calculations demonstrate the crucial roles of charge transfer state and the enhanced spin‐orbital coupling (SOC) matrix elements upon doping for achieving long‐lifetime phosphorescence beyond 600 nm. This research presents a strategy employing Cz‐based doping systems to facilitate RTP emissions extending from visible to deep red and NIR regions. [ABSTRACT FROM AUTHOR]

The maintenance of triplet excitons to produce room‐temperature phosphorescence while simultaneously improving the luminescence dissymmetry factor (glum) and photoluminescence quantum yield (PLQY) makes the preparation of circularly polarized room‐temperature phosphorescence (CP‐RTP) materials challenging. Herein, two chiral cocrystals are reported with CP‐RTP using S/R‐1‐(1‐Naphthyl)ethanol (S/R‐1‐nea) as the donor and 1,2,4,5‐Tetracyanobenzene (TCNB) as the acceptor. Simultaneous enhancement of glum and PLQY is accomplished, with the greatest phosphorescence in the PLQY of ≈31% and |glum| of 0.065, which is one of the highest |glum| in cocrystals. Doping two chiral cocrystals into the polyvinyl alcohol (PVA) matrix resulted in polymer films with circularly polarized long afterglow luminescence, indicating the potential for multilevel encryption applications. This study provides a novel approach to achieve the dual improvement of glum and phosphorescence PLQY, and broadens the application prospects of CP‐RTP materials. [ABSTRACT FROM AUTHOR]

Organic emitters that exhibit room‐temperature phosphorescence (RTP) in neat films have application potential for optoelectronic devices, bio‐imaging, and sensing. Due to molecular vibrations or rotations, the majority of triplet excitons recombine rapidly via non‐radiative processes in purely organic emitters, making it challenging to observe RTP in amorphous films. Here, a chemical strategy to enhance RTP in amorphous neat films is reported, by utilizing through‐space charge‐transfer (TSCT) effect induced by intramolecular steric hindrance. The donor and acceptor groups interact via spatial orbital overlaps, while molecular motions are suppressed simultaneously. As a result, triplets generated under photo‐excitation are stabilized in amorphous films, contributing to phosphorescence even at room temperature. The solvatochromic effect on the steady‐state and transient photoluminescence reveals the charge‐transfer feature of involved excited states, while the TSCT effect is further experimentally resolved by femtosecond transient absorption spectroscopy. The designed luminescent materials with pronounced TSCT effect show RTP in amorphous films, with lifetimes up to ≈40 ms, comparable to that in a rigid polymer host. Photoluminescence afterglow longer than 3 s is observed in neat films at room temperature. Therefore, it is demonstrated that utilizing intramolecular steric hindrance to stabilize long‐lived triplets leads to phosphorescence in amorphous films at room temperature. [ABSTRACT FROM AUTHOR]

Recently, biomass‐derived carbon dots (CDs) have attracted considerable attention in high‐technology fields due to their prominent merits, including brilliant luminescence, superior biocompatibility, and low toxicity. However, most of the biomass‐derived CDs only show bright fluorescence in diluted solution because of aggregation‐induced quenching effect, hence cannot exhibit solid‐state long‐lived room‐temperature phosphorescence (RTP) in ambient conditions. Herein, matrix‐free solid‐state RTP with an average lifetime of 0.50 s is realized in the CDs synthesized by one‐pot hydrothermal treatment of duck feather waste powder. To further enhance RTP lifetime, hydrogen bonding is introduced by employing polyols like polyvinyl alcohol (PVA) and phytic acid (PA), and a bimodal luminescent CDs/PVA/PA ink is exploited by mixing the CDs and polyols. Astonishingly, the CDs/PVA/PA ink screen‐printed onto cellulosic substrates exhibits unprecedented green RTP with average lifetime of up to 1.97 s, and the afterglow lasts for more than 14 s after removing UV lamp. Such improvement on RTP is proposed to the populated excited triplet excitons stabilized by rigid chains. Furthermore, the CDs/PVA/PA ink demonstrates excellent potential in anticounterfeiting and information encryption. To the best of the authors' knowledge, this work is the first successful attempt to fabricate matrix‐free ultra‐long RTP CDs by reclamation of the feather wastes for environmental sustainability. [ABSTRACT FROM AUTHOR]

Designing room‐temperature phosphorescent (RTP) hydrogels presents a unique challenge in comparison to RTP polymeric films and powders, due to the quenching of phosphorescence by water molecules within the hydrogel and their inherent softness. This study presents the first example of intrinsic RTP hydrogels without doping by luminophores or stiffening agents. The hydrogel is synthesized by copolymerizing acrylamide (Am) with N‐acryloyl‐aminoundecanoic acid (NAUA). The hydrophobic NAUA induces phase separation in the hydrogel network and the glass transition of the hydrophobic phase can stiffen the structure and constrain the mobility of water molecules and chain segments. Under such condition, the clustering of amide and carboxylic acid groups triggers the emission of RTP with a persistent afterglow exceeding 1.5 s, which is as good as the reported RTP hydrogels with dopants. When the hydrogel is heated above its glass transition temperature, its modulus drops quickly from 20.0 to 0.026 MPa within 2 s and RTP also diminishes. Taking advantage of the temperature‐switchable rigidity and RTP behavior, the hydrogels are endowed with functions such as shape memory, temperature‐sensing, and information concealment. [ABSTRACT FROM AUTHOR]

Developing efficiency and long‐lived room‐temperature phosphorescence (RTP) materials through straightforward methods is highly desired. In this work, a stepwise stabilization strategy was proposed by the coordination and in‐situ precipitation reactions among organic precursors, inorganic cation and anions, producing room‐temperature phosphorescence materials with high emission efficiency (phosphorescence quantum yield of 45 %). Structural and photophysical characterizations revealed the coordination reaction reduced the energy gaps between singlet and triplet states and stabilized the excited states of the guest molecules. The in‐situ precipitation reaction produced a solid matrix, which provided isolated environments for protecting the excitons from quenching. The applications of RTP materials in information encryption were demonstrated. The presented results provided a new clue for producing RTP materials, and extended their applications in wide fields. [ABSTRACT FROM AUTHOR]

Aiming to design new efficient organic triplet emitters, here a new electron‐accepting moiety 11,13‐dihydro‐12H‐dibenzo[a,c]imidazo[4,5‐i]phenazin‐12‐one (BIPO) are reported. Three new BIPO derivatives containing long alkyl chains, namely DBIPO (acceptor only), DBIPOBr (acceptor containing bromine atoms), and DBIPOAc with acridan moieties in a donor‐acceptor‐donor configuration, are designed and investigated. Efficient room temperature phosphorescence (RTP) is detected for the three compounds, stemming from a high‐lying (anti‐Kasha type) triplet emission occurring in the acceptor moiety. Additionally, the tetrahydrofuran‐ and dichloromethane DBIPOAc solutions show (i) a dual‐band photoluminescence profile stemming from anti‐Kasha emissions from high‐lying charge‐transfer (1CT) and locally excited (1LE) states, and (ii) a thermally activated delayed fluorescence (TADF) from the same high‐lying 1CT state. Importantly, DBIPOAc doped in rigid nonpolar polymer Zeonex simultaneously exhibits both TADF and RTP, with the emission quantum yield reaching 69.6%. Due to these properties, the BIPO derivatives constitute promising candidates as multi‐functional new emitters for the preparation of active layers of electroluminescent devices and optical oxygen/pressure sensors. The reasons for these interesting properties are discussed in detail. [ABSTRACT FROM AUTHOR]

The development of persistent room‐temperature phosphorescent (pRTP) hydrogels is important for the practical applications of organic phosphors. Unfortunately, the phosphorescence emission of nontraditional luminogens (NTLs) can be strongly quenched by water in hydrogel networks. Herein, a series of pRTP organohydrogels based on NTLs are prepared by dissolving poly(vinyl alcohol) (PVA), biuret (BIU) and poly(maleic acid) (PMAc) (or other nonaromatic macromolecular acids) in a glycerol/water mixed solvent, followed by a simple freezing‐thawing treatment. Very impressively, the organohydrogel exhibits remarkable excitation‐dependent and metal cation‐responsive phosphorescence with a maximum lifetime up to 782.8 ms at ambient conditions. Moreover, the organohydrogels treated with metal cations also have excitation‐dependent phosphorescence. Multidimensional information encryption can be achieved by simply printing solutions of metal cations onto the gel surface and switching the irradiation lights, or using gel blocks prepared with different macromolecular acids. Structural characterizations, mechanical tests, and comparative studies prove that hydrogen bonding between BIU and macromolecular chains leads to rigidification of molecular conformations and the cooperative effect of the components leads to the pRTP of the organohydrogels. This work provides a reliable strategy for the preparation of nonaromatic phosphorescent hydrogels with long afterglows and greatly expands the practical applications of phosphorescent materials. [ABSTRACT FROM AUTHOR]

Developing pure organic materials with ultralong lifetimes and balanced quantum efficiency is attractive but challenging. In this study, we propose a novel strategy to investigate external heavy atoms by linking molecular emitters with halogen through a flexible alkyl chain. X‐ray crystal analysis clearly reveal the halogen C−X‐π interactions, which can be tuned by halogen donors, as well as the distance and geometry between them. Impressively, DOPTZ‐C3Cl featuring a chloride atom as donor, exhibits a balanced long phosphorescence lifetime of 1351 ms and a phosphorescence quantum yield of 10.1 %. We also first demonstrate that Cl can induce more positive effect than heavier halogens (Br and I) on prolonging the lifetime. We envisage that the present study will expedite new molecular design to manipulate the room temperature phosphorescence via external heavy atom effect, and highlight a special C−Cl⋅⋅⋅π interaction for the development of ultralong phosphorescent materials. [ABSTRACT FROM AUTHOR]

The large‐scale fabrication of long‐lived and sustainable room‐temperature phosphorescence (RTP) materials with color‐tunable afterglow is of considerable practical importance in diverse optoelectronic applications but remains challenging. Herein, based on a process for the mass production of cellulose acetoacetate filaments, large‐scale RTP filaments are synthesized by introducing amino‐bearing luminophores via a mild enamine reaction. Attributed to efficient intersystem crossing facilitated by acetoacetyl and benzoyloxy groups alongside a rigid environment provided by multiple hydrogen bonding, the resulting filaments exhibit impressive RTP with a lifetime of 772 ms and a phosphorescence quantum yield of 45.06%. Furthermore, the afterglow color of RTP filaments is rationally modulated from blue to greenish‐yellow to rosy‐red through triplet‐to‐singlet Förster resonance energy transfer. Meanwhile, the formation of diverse clusters with comparable but different lifetimes leads to interesting excitation‐dependent afterglows. This work not only provides an effective strategy to construct long‐lived, color‐tunable, sustainable afterglows but also establishes large‐scale and continuous preparation routes for functional cellulose filaments. [ABSTRACT FROM AUTHOR]

Significant advances are made in understanding the structure‐property relationship in room‐temperature phosphorescence (RTP) materials. For example, intramolecular charge transfer (ICT) structural molecules based on electron donors(D) and electron acceptors(A) are an efficient method to achieve RTP. However, the ability to precisely regulate the singlet‐triplet energy gap (ΔEST) through molecular design to control RTP emissions remains constrained. Herein, a group of 4BN‐NP and 5BN‐NP isomers is reported with D and A position isomerization, where 4BN‐NP exhibits a photo‐induced orange afterglow phenomenon in PMMA. Calculations show that the spin‐orbit coupling (SOC) value of 4BN‐NP is greater compared to 5BN‐NP and the intersystem crossing (ISC) channel is more efficient, resulting in a smaller ΔEST value for 4BN‐NP. This indicates that the short ICT channel is more conducive to inducing phosphorescence emission. In addition, compound 4BN‐NP co‐doped with red fluorescent dyes (RhB, Rh6G, and RBNN) in PMMA produces phosphorescence resonance energy transfer (PRET), inducing red afterglow emission. Surprisingly, light‐activated yellow RTP can be obtained by attaching 4BN‐NP with polymethyl methacrylate (PMMA) to nylon filaments, and its phosphorescence intensity does not diminish even when it is immersed in water containing detergent solution, thus expanding the prospects of its application in textile encryption. [ABSTRACT FROM AUTHOR]

Some marine animals form long‐lived luminescence for predation, communication, camouflage, and anti‐predation. These marine animals demonstrate soft nature, sustainable glowing, and underwater emission, which are difficult to achieve in synthetic room temperature phosphorescence (RTP) materials. Inspired by these marine animals, here the study reports RTP hydrogels that show long‐lived phosphorescence (lifetime >500 ms and afterglow >10 s) in water. Exceptional underwater mechanical properties are simultaneously achieved, including tensile strength of 5.1 MPa, tensile strain of 452%, and toughness of 19.3 MJ m−3. The key to this achievement lies in the in situ phase separation microarchitecture formed between polyacrylamide (PAM) and its partial hydrolysates, which confines the motions of polymer chains and protects vulnerable triplet excitons from quenching of water. Such a strategy shows the merits of facile fabrication without laborious synthesis. In addition, these RTP hydrogels offer repeatable photoprinting and highly stability in water, providing a versatile platform for underwater applications of RTP materials, including information encryption and camouflage of marine animals. [ABSTRACT FROM AUTHOR]

We have accomplished concentration-controlled fluorescence and room-temperature phosphorescence color-changing emitters with excellent luminescence performance. [Display omitted] • The concentration dependent CNDs realized a spectral shift from blue to yellow regions. • The effect of self-assembly behavior on fluorescence color and excitation wavelength dependence of CNDs were further studied. • The concentration-dependent RTP CNDs@Urea materials were achieved. • The CNDs and CNDs@Urea materials can be used cell imaging, fingerprint recognition and anti-counterfeiting applications. Carbon nanodots (CNDs) exhibiting concentration dependent properties have been synthesized through a one-pot hydrothermal reaction process utilizing diethylenetriamine and l -aspartic acid. At solid-state or high concentrations, the CNDs display excitation-wavelength independent fluorescence (FL) emissions, while at low concentrations, they exhibit excitation-wavelength dependent FL emissions. Detailed characterization of the structure and optical properties reveals that the concentration dependent FL properties can be ascribed to the intrinsic-state luminescence of the CNDs at low concentrations and the assembled-state luminescence at solid-state/high concentrations. With the increase of concentration, the self-assembly behavior of CNDs may cause the transition from intrinsic-state dominant luminescence to assembled-state dominant luminescence, and finally lead to the red-shift of FL color. Furthermore, the CNDs@Urea composites possess adjustable room-temperature phosphorescence (RTP) from turquoise to yellow by controlling the CNDs doping concentration. CNDs with concentration dependent optical properties have shown certain potentials in the fields of cell imaging, fingerprint recognition and anti-counterfeiting applications. [ABSTRACT FROM AUTHOR]

Compact luminophores with long emission wavelengths have aroused considerable theoretical and practical interest. Organics with room‐temperature phosphorescence (RTP) are also desirable for their longer lifetimes and larger Stokes shifts than fluorescence. Utilizing the low electronic transition energy intrinsic to thiocarbonyl compounds, electron‐withdrawing groups were attached to the 4H‐pyran‐4‐thione core to further lower the excited state energies. The resulting mini‐phosphors were doped into suitable polymer matrices. These purely organic, amorphous materials emitted near‐infrared (NIR) RTP. Having a molar mass of only 162 g mol−1, one of the phosphors emitted RTP that peaked at 750 nm, with a very large Stokes shift of 15485 cm−1 (403 nm). Thanks to the good processability of the polymer film, light‐emitting diodes (LEDs) with NIR emission were easily fabricated by coating doped polymer on ultraviolet LEDs. This work provides an intriguing strategy to achieve NIR RTP using compact luminophores. [ABSTRACT FROM AUTHOR]

Despite the extensive research on room temperature phosphorescent (RTP) materials, it remains a great challenge to further improve the photophysical properties of RTP materials. In this study, the RTP emission of guest molecule is significantly enhanced by constructing binary matrices containing cyanuric acid (CA) and amino‐containing compounds. Systematic studies show that the strong interaction between the two components of binary matrix induced variations in the guest molecular configuration and excited state electron distribution, thus facilitating the production of more triplet excitons. Furthermore, the binary matrix also exhibits stronger domain‐limiting effect compared to the CA mono‐matrix, effectively inhibits the energy loss of triplet excitons due to quenching and non‐radiative transitions. The prepared binary matrix RTP materials present ultralong phosphorescence lifetime and high phosphorescence quantum yield (up to 3.21 s and 7.31%, respectively), and even achieve bright RTP emission in a variety of organic solvents and aqueous media. Moreover, the RTP emission intensity of the best binary matrix composite can reach more than 28 times that of the CA mono‐matrix composite, and the RTP lifetime can be extended by 1.51 s. [ABSTRACT FROM AUTHOR]

Hybrid metal halides (HMHs) with time‐resolved luminescence behavior promise to be a breakthrough in multi‐level anti‐counterfeiting, but controlling the dynamic switching between phosphorescence and fluorescence is extremely challenging. Herein, an array of 0D HMHs is constructed by screening the π‐conjugated ligand with room‐temperature phosphorescence (RTP). Compared to the organic chromophore, (ETPP)2ZrCl6 possesses a misaligned stacking and rigid structure, contributing to an improved phosphorescence quantum yield (ΦP = 27.50%) and an extended phosphorescence lifetime (τ = 0.6234 s), as the intervening of inorganic unit [ZrCl6]2− suppresses the energy losses caused by nonradiative relaxation and prompts the intersystem crossover (ISC) process. Not only that, the interplay of phosphorescence‐fluorescence dual‐mode emission can be intelligently controlled by doping the active metal Te4+, resulting in a dynamic switching between RTP phosphorescence and self‐trapped exciton (STE) fluorescence. DFT calculations reveal the governing origins of RTP‐STE from the intermolecular ISC channels and spin‐orbit coupling (SOC) coefficients. These precise images into periodic pixelated arrays enable the multi‐level anti‐counterfeiting and information encryption. This work proposes a fluorescence‐phosphorescence co‐modulating strategy under the premise of dissecting the structural origins for optimizing RTP phosphorescence, which paves the way for designing high‐security‐level anti‐counterfeiting materials. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Room‐temperature phosphorescence (RTP) materials have experienced rapid development due to their potential in organic light‐ emitting diode, information security, bioimaging, etc. However, the design of chiral organic phosphors with circularly polarized RTP (CPP) property remains a formidable challenge. Here, we introduce a chiral perturbation approach using a combination of chiral binaphthol and phenoselenazine derivative to achieve CPP. The photoactivated CPP in polystyrene (PS) film demonstrates a luminescence dissymmetry factor (glum), emission efficiency, and RTP lifetime up to 9.32 × 10–3, 27.0%, and 40.0 ms, respectively. The remarkable sensitivity of PS film to oxygen and temperature enables the adjustable emission colors, ranging from green to offwhite and blue under varying conditions. The doping systems, utilizing hosts of triphenylphosphine and 9‐phenylcarbazole, demonstrate an extended CPP lifetime of 85.9 ms and exhibit a persistent mechanoluminescence property with low pressure response threshold as low as 0.15 N. The information security provided by this CPP material was attained via the using of diverse emission colors and afterglow generated by distinct UV irradiation times and host materials. Alternately, it can also be achieved by observing different emission patterns using R‐ and L‐polarizer. The research has presented a reliable approach for producing CPP materials with high emission efficiency and glum. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Room‐temperature phosphorescence (RTP) materials have experienced rapid development due to their potential in organic light‐ emitting diode, information security, bioimaging, etc. However, the design of chiral organic phosphors with circularly polarized RTP (CPP) property remains a formidable challenge. Here, we introduce a chiral perturbation approach using a combination of chiral binaphthol and phenoselenazine derivative to achieve CPP. The photoactivated CPP in polystyrene (PS) film demonstrates a luminescence dissymmetry factor (glum), emission efficiency, and RTP lifetime up to 9.32 × 10–3, 27.0%, and 40.0 ms, respectively. The remarkable sensitivity of PS film to oxygen and temperature enables the adjustable emission colors, ranging from green to offwhite and blue under varying conditions. The doping systems, utilizing hosts of triphenylphosphine and 9‐phenylcarbazole, demonstrate an extended CPP lifetime of 85.9 ms and exhibit a persistent mechanoluminescence property with low pressure response threshold as low as 0.15 N. The information security provided by this CPP material was attained via the using of diverse emission colors and afterglow generated by distinct UV irradiation times and host materials. Alternately, it can also be achieved by observing different emission patterns using R‐ and L‐polarizer. The research has presented a reliable approach for producing CPP materials with high emission efficiency and glum. [ABSTRACT FROM AUTHOR]

Afterglow materials have garnered significant interest due to distinct photophysical characteristics. However, it is still difficult to achieve long afterglow phosphorescence from organic molecules due to aggregation‐caused quenching (ACQ) and energy dissipation. In addition, most materials reported so far have long afterglow emission only at room or even low temperatures, and mainly use UV light as an excitation source. In this work, we report a strategy to achieve high temperature long afterglow emission through the assembly of isolated 0D metal‐organic cages (MOCs). In which, both ACQ and phosphorescence quenching effects are effectively mitigated by altering the stacking mode of organic chromophores through orthogonally anchoring into the edges of cubic MOCs. Furthermore, improvement in molecular rigidity, promotion of spin‐orbit coupling and broadening of the absorption range are achieved through the MOC‐engineering strategy. As a result, we successfully synthesized MOCs that can produce afterglow emission even after excitation by WLEDs at high temperatures (380 K). Moreover, the MOCs are capable of generating afterglow emissions when excited by mobile phone flashlight at room temperature. Given these features, the potential applications of MOCs in the visual identification of explosives, information encryption and multicolor display are explored. [ABSTRACT FROM AUTHOR]

Organelle-targeted imaging can provide information on cellular functions and intracellular interactions, being significant for disease diagnosis. The use of room-temperature phosphorescence (RTP) in organelle-targeted imaging can fully utilize its unique characteristics of long wavelength and deep penetration. However, this technology has long been plagued by insufficient probe targeting and limited luminous intensity. In this work, we prepared a series of complexes composed of multicationic persulfurated arenes and biomacromolecules via electrostatic interactions in 1:1 stoichiometry for high-contrast mitochondrial-targeted RTP imaging. Such an electrostatic interaction design effectively prevented the self-aggregation of the probes, which is not conducive to mitochondrial targeting. Simultaneously, it suppressed the non-radiative decay to the maximum extent, enabling the probes to exhibit strong RTP signals both in aqueous solution and at the cellular level. Furthermore, the biomacromolecules can serve as carriers for an electrostatic interaction transfer of the persulfurated arenes to mitochondria. This leads to high mitochondrial targeting Pearson's correlation coefficients of the probes and high-contrast RTP imaging effects, as well as the independence of the co-incubated probe concentration. These results provide new insights for the development of targeted imaging technologies. [ABSTRACT FROM AUTHOR]

The long-lived room-temperature phosphorescence (RTP) originating from thiophene boronate polyvinyl alcohol (PVA) has enabled the creation of metal-ion-responsive RTP films doped with spirolactam ring-containing rhodamine 6G (1). In this study, RTP-active PVA films, namely, TDB@PVA and ATB@PVA, were prepared through boronate esterification of thiophene-2,5-diboronic acid (TDB) and 5-acetylthiophene-2-boronic acid (ATB) with the diol units of PVA. The delayed emission properties were evaluated, revealing an emission band at 477 nm with a turquoise afterglow for TDB@PVA and at 510 nm with a green afterglow for ATB@PVA after UV light irradiation ceased. The photophysical properties were assessed using TD-DFT and DFT calculations at the B3LYP/cc-pVDZ level. N-(rhodamine-6G)lactam dye with a salicylimine unit (1) was doped into the RTP-based PVA films, producing a multicolored afterglow upon the addition of metal ions. This phenomenon is explained by a triplet-tosinglet Förster-type resonance energy transfer process from the cross-linked thiophene boronate in PVA to the metal-ion-activated colored form of 1. This photophysical feature finds applicability in encryption techniques. Notably, the reversible metal-ligand coordination of 1 in the PVA system enabled a write/erase information process. [ABSTRACT FROM AUTHOR]

The efficient utilization of clean and safe sunlight as an excitation source for room‐temperature phosphorescent (RTP) materials is crucial for practical applications in solar energy. Herein, sunlight‐activated RTP nitrogen‐doped carbon dots @ alumina (N‐CDs@Al2O3) composites with long lifetime and exceptional stability are designed and fabricated using an in situ preparation strategy. The N‐CDs@Al2O3 display bright yellow RTP (more than 18 s to the naked eye) when activated by sunlight. The results indicate that the introduction of nitrogen into the CDs not only promotes the effective filling of triplet excitons but also facilitates the red‐shift of the absorption spectrum of the CDs. The high rigidity structure of Al2O3 and stable strong covalent bonds effectively protect the triplet excitons. Additionally, the numerous oxygen vacancy defects formed under appropriate calcination conditions effectively store and release triplet excitons. Finally, the application of N‐CDs@Al2O3 in multi‐color 3D artworks, defense markings, and emergency signs is demonstrated. This work provides design principles and feasible strategies for the development of new sunlight‐activated RTP materials. [ABSTRACT FROM AUTHOR]

Donor–acceptor (D–A) structure with charge transfer (CT) effect is widely utilized in the construction of organic luminescent materials. The adjustment of their CT effect and related luminescent property usually relies on the changes of molecular structure with different D or A moieties, which will lead to some uncertainties in structure‐property relationship. With the aim to explore the clear inherent luminescent mechanism for D–A molecule with CT effect, it is ideal that the regulation of intramolecular charge transfer in one same D–A molecule can be realized. Accordingly, three D–A type organic phosphorescence luminogens are designed and synthesized. Once being doped into different polymer matrixes, disparate charge transfer effects and related room temperature phosphorescence (RTP) properties can be achieved for a single molecule. Subsequent experiments confirm that different distributions of molecules with locally excited (LE) state and CT state are mainly responsible for their distinct RTP behaviors, exhibiting the well‐clarified structure‐property relationship of D–A type phosphorescence luminogens. Furthermore, the transition from CT to LE state can even be realized through chemical reaction, leading to the activated RTP effect for practical applications. [ABSTRACT FROM AUTHOR]

Organic afterglow can be generated from persistent thermally activated delayed fluorescence (pTADF) or organic ultralong room temperature phosphorescence (OURTP), but the pTADF plus OURTP type organic afterglow is challenging to achieve, especially for the color‐tunable and high‐temperature ones. Herein, an accessible strategy toward such dual‐mode afterglow is presented by doping the indolo[3,2‐b]carbazole (ICZ‐p1) into polymethyl methacrylate (PMMA). The resulting films exhibit photo‐activated afterglow with two persistent emission peaks of ca. 435 and 497 nm. Impressively, their longest lifetimes respectively reach to 2.28 and 2.47 s at 298 K, along with 0.32 and 0.42 s at 360 K, enabling the afterglow at room and high temperature. Experimental and theoretical results reveal that the photo‐activated afterglow is associated with the elimination of molecular O2 inside film and composed by the pTADF with multi‐resonance (MR) effect and OURTP. By altering the temperature from 77 to 358 K, the color‐tunable afterglows of green and blue are harvested at such temperature ranges. Benefiting from the multi‐resonance thermally activated delayed fluorescence (MRTADF) characteristics, this emitter can release narrow‐band electroluminescence. Consequently, the results obtained here may offer important references for chasing MRTADF plus OURTP‐type dual‐mode organic afterglow showing color‐tunable and high‐temperature features. [ABSTRACT FROM AUTHOR]

Polymeric room‐temperature phosphorescence (RTP) materials especially multicolor RTP systems hold great promise in concrete applications. A key feature in these applications is a triplet charge transfer transition. Aromatic electron donors and electron acceptors are often essential to ensure persistent RTP. There is much interest in fabricating non‐aromatic charge‐transfer‐mediated RTP materials and it still remains a formidable challenge to achieve color‐tunable RTP via charge transfer. Herein, a charge‐transfer‐mediated RTP material by embedding quinoline derivatives within a non‐aromatic polymer matrix such as polyacrylamide (PAM) or polyvinyl alcohol (PVA) is developed. Through‐space charge transfer (TSCT) is achieved upon alkali‐ or heat treatment to realize a long phosphorescence lifetime of up to 629.90 ms, high phosphorescence quantum yield of up to 20.51%, and a green‐to‐blue afterglow for more than 20 s at room temperature. This color‐tunable RTP emerges from a nonaromatic polymer to single phosphor charge transfer that has rarely been reported before. This finding suggests that an effective and simple approach can deliver new color‐tunable RTP materials for applications including multicolor display, information encryption, and gas detection. [ABSTRACT FROM AUTHOR]

Nonconventional luminophores have received increasing attention, owing to their fundamental importance, advantages in outstanding biocompatibility, easy preparation, environmental friendliness, and potential applications in sensing, imaging, and encryption. Purely organic molecules with outstanding fluorescence and room‐temperature phosphorescence (RTP) have emerged as a new library of benign afterglow agents. However, the cost, toxicity, high reactivity, and poor stability of materials also limit their practical applications. Therefore, some natural products, synthetic compounds, and biomolecules have entered horizons of people. The as‐designed exhibits sky blue and green fluorescence emission and green RTP emission (a lifetime of 343 ms and phosphorescence quantum of 15.3%) under air condition. This study presents an organic fluorescence for biological imaging and RTP for anti‐counterfeiting and encryption based on amino acids, maleic anhydride and 4‐vinylbenzenesulfonic acid sodium salt hydrate. This study provides a strategy for nonconventional luminophores in designing and synthesizing pure organic RTP materials. [ABSTRACT FROM AUTHOR]

Room temperature phosphorescence rarely occurs from pure organic molecules, especially in the solid‐state. A strategy for the design of highly emissive organic phosphors is still hard to predict, thus impeding the development of new functional materials with the desired optical properties. Herein, we analyze a family of alkyl and aryl‐substituted persulfurated benzenes, the latter representing a class of organic solid‐state triplet emitters able to show very high emission quantum yield at room temperature. In this work, we correlate structural parameters with the photophysical properties observed in different experimental conditions (diluted solution, crystalline and amorphous phase at RT and low temperature). Our results, corroborated by a detailed computational analysis, indicate a close relationship between the luminescence properties and i) the nature of the substituents on the persulfurated core, ii) the adopted conformations in the solid state, both in crystalline and amorphous phases. These factors contribute to characterize the lowest‐energy lying excited‐state, its deactivation pathways, the phosphorescence lifetime and quantum yield. These findings provide a useful roadmap for the development of highly performing purely organic solid‐state emitters based on the persulfurated benzene platform. [ABSTRACT FROM AUTHOR]

Avoiding the tedious process of crystal cultivation and directly obtaining organic crystals with desirable phosphorescent performance is of great significance for studying their structure and properties. Herein, a set of benzophenone‐cored phosphors with bright green afterglow are obtained on a large scale through in‐situ generation via an end‐capping strategy to suppress non‐radiative triplet excitons and reinforce the intermolecular interactions. The ordered arrangement of phosphors with alkyl‐cyano groups as regulators is crucial for the enhancement of room‐temperature phosphorescence (RTP) emission, which has been further verified by the attenuated lifetimes in isolated states through the formation of inclusion complexes upon binding with pillar[5]arenes. Moreover, the hierarchical interactions of phosphors, including hydrogen bonding, π‐π stacking interactions, and van der Waals forces, are quantified by crystal structures and theoretical calculation to deeply interpret the origins of RTP emission. With this study, we provide a potential strategy for the direct acquisition of crystalline organic phosphors and modulation of RTP. [ABSTRACT FROM AUTHOR]

Abstract Recently, biomass‐derived carbon dots (CDs) have attracted considerable attention in high‐technology fields due to their prominent merits, including brilliant luminescence, superior biocompatibility, and low toxicity. However, most of the biomass‐derived CDs only show bright fluorescence in diluted solution because of aggregation‐induced quenching effect, hence cannot exhibit solid‐state long‐lived room‐temperature phosphorescence (RTP) in ambient conditions. Herein, matrix‐free solid‐state RTP with an average lifetime of 0.50 s is realized in the CDs synthesized by one‐pot hydrothermal treatment of duck feather waste powder. To further enhance RTP lifetime, hydrogen bonding is introduced by employing polyols like polyvinyl alcohol (PVA) and phytic acid (PA), and a bimodal luminescent CDs/PVA/PA ink is exploited by mixing the CDs and polyols. Astonishingly, the CDs/PVA/PA ink screen‐printed onto cellulosic substrates exhibits unprecedented green RTP with average lifetime of up to 1.97 s, and the afterglow lasts for more than 14 s after removing UV lamp. Such improvement on RTP is proposed to the populated excited triplet excitons stabilized by rigid chains. Furthermore, the CDs/PVA/PA ink demonstrates excellent potential in anticounterfeiting and information encryption. To the best of the authors' knowledge, this work is the first successful attempt to fabricate matrix‐free ultra‐long RTP CDs by reclamation of the feather wastes for environmental sustainability.

Herein we employ density functional theory (DFT) and linear response time-dependent density functional theory (LR-TDDFT) together with our own n-layered integrated molecular orbital and molecular mechanics (ONIOM)-based quantum mechanical/molecular mechanics (QM/MM) methods to study the room-temperature phosphorescent (RTP) micro-mechanism of several benzonitrile-carbazole (CzBz-X) molecules (i.e. CzBz-H, CzBz-F, CzBz-Cl, CzBz-Br) in liquid and solid state. Based on the calculated the ground- and excited-state geometric and electronic structures, the absorption and emission spectra are simulated and agreed well with previous experimental observation. The intersystem crossing (ISC) rate constants of S1 -> T1 obtained by the formula derived from the Fermi golden rule are small in liquid state, while the ISC rate constants are comparable to the relative radiative rate constants of S1 ->S0 in solid state. Molecular vibrations are restricted in solid state, which lead to the decrease of reorganization energies and Huang-Rhys factors, and the increase of ISC rate constants. Both the heavy-atom effect and aggregation effect play important roles in improving the RTP performance in CzBz-X compounds. Through quantum chemistry calculations, the present work not only elucidates the RTP mechanism and the significance of heavy-atom and aggregation effects in CzBz-X, but also provides new insights for designing novel RTP materials.

Circularly polarized phosphorescence (CPP) is increasingly recognized in materials science for its unique applications in optoelectronic devices, chiral recognition, and bioimaging. This study underscores a novel directed chiral self‐assembly strategy of purely organic phosphors into supramolecular nanostructures to achieve bright room‐temperature circularly polarized phosphorescence (RT‐CPP). RT‐CPP molecules are built on an aromatic carbonyl structure having also Br to mix (n,π*) and (π,π*) characters and to enable the heavy atom effect. Side chains are rationally designed to have strong hydrogen bonding, van der Waals interactions, and a chiral center for directed chiral self‐assembly into supramolecular nanostructures. The tightly packed resulting supramolecular nanostructures also impower efficient suppression of molecular motions, thereby minimizing non‐radiative decay and facilitating bright CPP emission at room temperature. The developed self‐assembled supramolecular structures exhibit RT‐CPP with the dissymmetry factor (glum) of ≈10−3, a high phosphorescence quantum yield of 4.1%, and a rapid triplet decay time of 180 microseconds. The presented molecular design principle enabling RT‐CPP from purely organic phosphors may pave the way for novel photonic materials. [ABSTRACT FROM AUTHOR]

Herein, cucurbituril‐regulated supramolecular multi‐dimensional organic framework constructed is reported by tetraphenylvinyl grafted bromophenylpyridine salt derivatives (TPE‐BrN) and cucurbit[n]uril (n = 6, 7, 8) via non‐covalent cross‐linked, giving supramolecular macrocycle‐confined fluorescence‐phosphorescence dual emission at 560 and 510 nm in solid state. Different from the formation of TPE‐BrN⊂CB[6] complexes and TPE‐BrN⊂CB[7] nanoparticle, TPE‐BrN⊂CB[8] manifested high‐efficient 2D network assembly. TPE‐BrN⊂CB[8] assembly can effectively activate triplet‐state to singlet‐state Förster resonance energy transfer (TS‐FRET) with long‐lived near‐infrared emission at 675 nm via doping organic dye Nile red (NiR) and the energy transfer efficiency reached up to 99%. Although CB[7] can also induce the typical phosphorescence emission at 510 nm, there is no TS‐FRET occurring after doping NiR into TPE‐BrN⊂CB[7] assembly due to the formation of different assembly modes. The multicolor long‐lived emission has been demonstrated very well based on the TS‐FRET process activated by CB[8] macrocyclic confined 2D organic framework, which can be successfully applied to fingerprint imaging and the construction of logic gate systems. It provides a novel method for supramolecular macrocycle confined phosphorescence regulation and the development of luminescent materials. [ABSTRACT FROM AUTHOR]

Organic photoluminescent materials with room‐temperature phosphorescence (RTP) are of great interest, yet achieving RTP in hydrogels faces challenges due to water‐quenching effects. In this study, a straightforward method is presented to achieve RTP hydrogel using a self‐healing and salt‐hardening hydrogel. The hydrogel is synthesized by polymerizing acrylic acid (AA) with diethylenetriamine (DETA) as the dynamic crosslinker. The poly(acrylic acid)/DETA hydrogel could achieve an afterglow lasting 1.6 s after soaking with NaBr solution. The salt‐enhanced hydrophobic aggregation of the hydrogel network promotes the clustering of carboxyl groups and oxygen atoms, resulting in a rigid environment that suppresses nonradioactive transitions and leads to the manifestation of RTP. Additionally, the dynamic association of AA‐DETA allows the freeze‐dried hydrogel powder to be blended with various hydrophobic dyes, leading to a remodelable hydrogel with delayed emission of multiple colors. In general, by combining salt‐hardening property with self‐healing property together, a RTP hydrogel platform that can be facilely loaded with various organic dyes is proposed. [ABSTRACT FROM AUTHOR]

Supramolecular organic framework (SOF) has recently garnered significant research interest in the field of luminescent materials. However, SOF with room‐temperature phosphorescence emission in solution is very rare due to the quenching of dissolved oxygen and free molecular motions, which would lead to nonradiative deactivation of triplet exciton in liquid state. In this work, a 3D cationic phosphorescent SOF is synthesized through host‐guest interaction between CB[8] and a tetrahedral monomer TBBP, which can rapidly adsorb anionic guests in solution. When anionic dyes are introduced, triplet to singlet Förster resonance energy transfer (TS‐FRET) in solution can be achieved, and delayed fluorescence with large Stokes shift can be realized. Additionally, when anionic drugs are introduced, the phosphorescence of TBBP‐CB[8] can be quenched due to charge transfer, enabling the detection of drugs through phosphorescence signals. Taking advantage of the fast adsorption property of 3D SOF, an INHIBIT logic gate with three inputs and two outputs is constructed. These findings provide a novel method to prepare phosphorescent functional materials and a new pathway to construct TS‐FRET system in solution. [ABSTRACT FROM AUTHOR]

Despite rapid progress and wide applications of room temperature phosphorescence (RTP) materials, it is still a great challenge to optimize the RTP activity through rational structural design at a molecular level. Herein, a successful cationic engineering strategy is demonstrated to modulate the crystal flexibility achieving controllable RTP in a new pair of metal halides [APML]ZnCl4 ([APML] = N‐(3‐Aminopropyl)morpholine) and [AEML]ZnCl4 ([AEML] = N‐(2‐Aminoethyl)morpholine). Both halides display blue fluorescence under 365 nm UV. Comparing with longer [APML]+, shorter [AEML]+ significantly enhances crystal rigidity and restrains non‐radiative scattering, boosting photoluminescence quantum yield (PLQY) from 18.89% to 22.41%. Synchronously, enhanced crystal rigidity significantly promotes the inter‐system crossing from singlet to triplet excited states. As a consequence, [AEML]ZnCl4 displays long‐lived green RTP property with millisecond scale lifetime in contrast to the blank RTP activity of [APML]ZnCl4. Comprehensive investigations demonstrate that the energy transfer between inorganic and organic components greatly changes the redistribution of singlet and triplet excited states, resulting in distinct phosphorescence activity. The different short‐lived blue fluorescence and long‐lived green phosphorescence provide a color‐time‐dual‐resolved luminescent tag with advanced applications in anti‐counterfeiting, etc. This work highlights a new structural engineering strategy to achieve controllable RTP affording a guide to rationally design RTP materials. [ABSTRACT FROM AUTHOR]

Organic room‐temperature phosphorescence (RTP) materials are actively explored as attractive candidates for optoelectronic and bioelectronics applications given their unique long‐lived excited‐state features and inherent merits of low‐cost, appreciable functionality, and good biocompatibility. In recent years, many efforts in molecular design and aggregation modulation are devoted to achiev efficient RTP from organics, among which an emerging strategy focuses on confining chromophores within polymer matrices. Polymers possess intertwined chains making them a good platform to restrain the nonradiative decays and quenching, allowing the triplet excitons to survive a long time enough for emission at room temperature. Progress relating to polymer‐based organic RTP materials is highlighted as a new creative subject in the field. This review outlines recent advancements in polymer‐based organic RTP materials. The fundamental mechanism of organic RTP is first presented. Thereafter, design considerations and strategies to construct polymer‐based organic RTP materials are summarized in detail. Several promising progresses in the proposed use of these RTP materials, such as encryption and anti‐counterfeiting, sensors, and bioimaging are overviewed. Finally, the challenges and future perspectives are discussed to emphasize the directions that deserve focus attention in the field. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Kasha's exciton model proposes that T1 energy levels of organic compounds are insensitive to molecular aggregation and microenvironment change because of negligible small transition dipole moments of T1 states. This model holds true in most organic systems till now. Here we report the fabrication of twisted organic phosphors with intramolecular charge transfer characters and flexible molecular structures. When doped into different organic matrices, the twisted phosphor adopts different conformation, exhibits distinct phosphorescence colors and T1 energy levels, which violates Kasha's exciton model in organic system. Given that the change of phosphorescence colors and maxima can be readily distinguished by human eyes and conventional instrument, the twisted phosphors would be exploited as a new type of molecular probe, which would exhibit potential application in optical sensing and stimuli‐responsive systems. [ABSTRACT FROM AUTHOR]

Organic scintillators have recently gained considerable attentions in X‐ray detection for their potential applications in biomedical radiograph and security inspection. However, the weak X‐ray absorption and/or inefficient exciton utilization have limited the development and commercialization of organic scintillators. Currently, high‐performance X‐ray organic scintillators are scarce and organic scintillators with dual triplet‐harvesting channels have not been explored before. Here, we develop several proof‐of‐concept sulfone‐based organic molecules, C1–C7, using different alkoxy chains to manipulate molecular packing mode. These materials exhibit dual triplet‐harvesting channels of thermally activated delayed fluorescence (TADF) and room‐temperature phosphorescence (RTP) in aggregated state. Inspiringly, these molecules display distinct radioluminescence under the X‐ray stimulation. Among them, C6 behaves the highest light yield of 16,558 photons MeV−1. Moreover, clear X‐ray images are demonstrated in both aggregated state and single‐molecule level. High spatial resolutions of 15.0 and 10.6 line pairs per millimeter (lp mm−1) are achieved for rigid and flexible scintillator screens, exceeding most reported organic and conventional inorganic scintillators. These results highlight the great potential of organic molecules with TADF and RTP nature for efficient X‐ray scintillation and imaging. [ABSTRACT FROM AUTHOR]

Tunable‐lifetime room‐temperature phosphorescence (RTP) materials have been widely studied due to their broad applications. However, only few reports have achieved wide‐range lifetime modulation. In this work, ultra‐wide range tunable‐lifetime efficient dark blue RTP materials were realized by doping methyl benzoate derivatives into polyvinyl alcohol (PVA) matrix. The phosphorescence lifetimes of the doped films can be increased from 32.8 ms to 1925.8 ms. Such wide range of phosphorescence lifetime modulation is extremely rare in current reports. Moreover, the phosphorescence emission of the methyl 4‐hydroxybenzoate‐doped film is located in the dark blue region and the phosphorescence quantum yield reaches as high as 15.4 %, which broadens their applications in organic optoelectronic information. Further studies demonstrated that the reason for the tunable lifetime was that the magnitude of the electron‐donating ability of the substituent group modulates the HOMO–LUMO and singlet‐triplet energy gap of methyl benzoate derivatives, as well as the ability to non‐covalent interactions with PVA. Moreover, the potential applications of luminescent displays and optical anti‐counterfeiting of these high‐performance dark blue RTP materials have been conducted. [ABSTRACT FROM AUTHOR]

Molecular ultralong room‐temperature phosphorescence (RTP), exhibiting multiple stimuli‐responsive characteristics, has garnered considerable attention due to its potential applications in light‐emitting devices, sensors, and information safety. This work proposes the utilization of photochemical cascade processes (PCCPs) in molecular crystals to design a stepwise smart RTP switch. By harnessing the sequential dynamics of photo‐burst movement (induced by [2+2] photocycloaddition) and photochromism (induced by photogenerated radicals) in a bismuth (Bi)‐based metal‐organic halide (MOH), a continuous and photo‐responsive ultralong RTP can be achieved. Furthermore, utilizing the same Bi‐based MOH, diverse application demonstrations, such as multi‐mode anti‐counterfeiting and information encryption, can be easily implemented. This work thus not only serves as a proof‐of‐concept for the development of solid‐state PCCPs that integrate photosalient effect and photochromism with light‐chemical‐mechanical energy conversion, but also lays the groundwork for designing new Bi‐based MOHs with dynamically responsive ultralong RTP. [ABSTRACT FROM AUTHOR]

Supramolecular room temperature phosphorescence (RTP) materials are attractive due to their excellent RTP characteristics and water resistance. By evaluating the photophysical properties of HA/BisNpI‐doped materials, it is proved that hyaluronic acid (HA) is a promising matrix and the rigid plane N,N′‐(1,4‐phenylene)‐bis(1,8‐naphthalimide) (Ph‐BisNpI) is an excellent luminescent guest molecule for constructing RTP materials. Moreover, it is found that γ‐cyclodextrin (γ‐CD) can successfully bind BisNpI guest molecule. Accordingly, a tightly arranged ternary supramolecular system with HA as matrix, Ph‐BisNpI as the guest, and γ‐CD as the host is constructed by host‐guest interaction and hydrogen bonding. As expected, the obtained ternary supramolecular system HA/Ph@CD8 displays a superior RTP performance (52.7 ms longer lifetime than HA/Ph), water‐resistance, and even aqueous RTP (τ = 207 µs), which significantly extends the application of RTP in aqueous solution. These results are possibly attributed to the inclusion of γ‐CD on Ph‐BisNpI guest molecules and the self‐assembly of γ‐CD and HA to form a rigid hydrogen bonding network, which effectively inhibits the non‐radiative decay of Ph‐BisNpI and shields the triplet excitons from water and oxygen. Furthermore, the prepared ternary supramolecular RTP materials are successfully used as anticounterfeiting ink and exhibit broader application prospects in water environments. [ABSTRACT FROM AUTHOR]