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Development of self-healing and photostimulated luminescent supramolecular polymeric materials is important for artificial soft materials. A supramolecular polymeric hydrogel is reported based on the host-guest recognition between a β-cyclodextrin (β-CD) host polymer (poly-β-CD) and an α-bromonaphthalene (α-BrNp) polymer (poly-BrNp) without any additional gelator, which can self-heal within only about one minute under ambient atmosphere without any additive. This supramolecular polymer system can be excited to engender room-temperature phosphorescence (RTP) signals based on the fact that the inclusion of β-CD macrocycle with α-BrNp moiety is able to induce RTP emission (CD-RTP). The RTP signal can be adjusted reversibly by competitive complexation of β-CD with azobenzene moiety under specific irradiation by introducing another azobenzene guest polymer (poly-Azo)., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

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]

Comprehensive Summary: Monitoring of sweat pH plays important roles in physiological health, nutritional balance, psychological stress, and sports performance. However, the combination of functional MOFs with phosphorescent material to acquire the real‐time physiological information, as well as the application of dual mode anti‐counterfeiting, has seldom been reported. Herein, we developed multifunctional gel films based on MOFs and phosphorescent dyes which responded to H+ ions and the related mechanism was studied in detail. Upon exposure to H+, the composite gel film exhibited decreased fluorescent signal but enhanced room temperature phosphorescence (RTP), which could be utilized for sweat pH sensing through a dual‐mode. Moreover, multifunctional gel films exhibited a potential application in information encryption and anti‐counterfeiting by designing of stimulus responsive multiple patterns. This research provided a new avenue for portable and non‐invasive sweat pH monitoring methods while also offering insights into stimulus‐responsive multifunctional materials. [ABSTRACT FROM AUTHOR]

Room-temperature phosphorescence (RTP) plays an important role in the field of information encryption due to its ability to effectively eliminate interference caused by background fluorescence (FL). Herein, a series of RTP carbon dots (CDs) containing different nitrogen contents were prepared via a molten salt method. In the reaction system, magnesium chloride and potassium nitrate were used as doping salts to form salt shells, and potassium nitrate was used as salt medium to promote the reaction. By adjusting the amount of melamine, the synthesized CDs-3 exhibit cyan FL and yellow phosphorescence, with a long phosphorescence lifetime of 673.29 ms. It is worth noting that the yellow RTP can be maintained either in dry or wet state, which facilitates for the information encryption. It is suggested that the salt shell composed of magnesium salt with high charge density has a rigid structure, which inhibits the nonradiative transition process of the triplet-state exciton and enhances the phosphorescence intensity. Unfortunately, when the amount of melamine increases to a certain extent, due to the incomplete encapsulation of the salt shell, the phosphorescence of the prepared CDs quenches accordingly. In addition, CDs-3 can also be mixed with epoxy resin to obtain the desired fluorescent/phosphorescent composites. These excellent optical properties indicate that the synthesized CD materials have great development prospects in fields such as anti-counterfeiting and luminescent materials. [ABSTRACT FROM AUTHOR]

Room-temperature phosphorescence carbon dots (CDs) show the highlighted advantages in chemical sensing and bioimaging owing to its long lifetime, however, acquiring the efficient phosphorescence of carbon dots is still encountering difficulty due to the spin prohibition. Here, we synthesized one type of CDs through one-step hydrothermal method. To be specific, the CDs displayed the blue fluorescence in aqueous, and emitted the bright green phosphorescence when being coated on the filter paper. Importantly, introducing coumarin to the CDs resulted in the distinct quenching of both its fluorescence and phosphorescence. Based on this phenomenon, we successfully established a dual-channel detection of coumarin. The fluorescence detection channel exhibited a linear range of 5–350 μM with a detection limit of 0.196 μM, while the phosphorescence detection channel achieved a linear range of 50–1000 μM with a detection limit of 0.268 μM. The further investigation revealed that IFE and SQE were mainly responsible for the fluorescence quenching of CDs, while the phosphorescence quenching was originated from the increased energy gap between the singlet and triplet states (ΔE ST) of CDs, thus obstructing the ISC process. Moreover, we employed the CDs as the phosphorescent ink for anti-counterfeiting. [Display omitted] [ABSTRACT FROM AUTHOR]

A purely organic supramolecular assembly emitting three‐photon room‐temperature phosphorescence (RTP) is constructed from a macrocyclic host, cucurbit[8]uril (CB[8]), and 4‐bromophenyl pyridine salt having an alkyl chain length of 6 or 12 carbon atoms (6C and 12C, respectively). Benefiting from macrocyclic host confined guests, the encapsulation of 12C and 6C in the CB[8] cavity results in three‐photon absorption and subsequent near‐infrared (NIR) phosphorescence emission. Notably, secondary assembly with sulfonated β‐cyclodextrin (SCD) further enhances the phosphorescence emission of the multilevel supramolecular assembly. NIR‐delayed fluorescence via a light‐harvesting phosphorescent energy transfer system is achieved by adding Nile blue as a substrate. Comparison of 12C/CB[8]/SCD and 6C/CB[8]/SCD shows that a long hydrophobic layer is more conducive to stabilizing NIR‐delayed fluorescence emission. These findings indicate that multilevel supramolecular assemblies can be used for three‐photon‐excited NIR‐delayed fluorescence and RTP imaging of cancer cells, which greatly expands the biological applications of pure organic RTP materials. [ABSTRACT FROM AUTHOR]

To improve room‐temperature phosphorescence (RTP) property, thianthrene (TA) is chemically modified into three intramolecular dimers (1TA1TA, 1TA2TA, and 2TA2TA) at different active sites. They all show dual‐emission of fluorescence and RTP after deoxygenation when they are dispersed in polymer matrix to form films. As for the RTP emission among their films, 2TA2TA shows the largest red shift peaking at 540 nm, the longest lifetime of 36.5 ms, and the highest RTP efficiency of 40.7%. These RTP characteristics enable 2TA2TA to act as a self‐referenced ratiometric and colorimetric probe for oxygen sensing and detection at low concentration. As a result, 2TA2TA exhibits the highest quenching efficiency of 98.4% and highest sensitivity (KSV = 13.32 KPa−1) for quantitative oxygen detection. Besides, these oxygen‐sensitive materials can also be used to study aerodynamics through a direct and visual observation of emission intensity/color distribution. Overall, the new‐generation optical probe will be developed in oxygen sensing and detection with high sensitivity, good reversibility, and reproducibility by using the pure organic materials with single‐molecule dual‐emission of fluorescence and RTP through the dispersion of the materials in polymeric host. [ABSTRACT FROM AUTHOR]

Despite ongoing research into photocontrolled supramolecular switches, reversible photoswitching between room-temperature phosphorescence (RTP) and delayed fluorescence is rare in the aqueous phase. Herein, an efficient RTP-fluorescence switch based on a cascaded supramolecular assembly is reported, which is constructed using a 6-bromoisoquinoline derivative (G3), cucurbit[7]uril (CB[7]), sulfonatocalix[4]arene (SC4A4), and a photochromic spiropyran (SP) derivative. Benefiting from the confinement effect of CB[7], initial complexation with CB[7] arouses an emerging RTP signal at 540 nm for G3. This structure subsequently coassembles with amphiphilic SC4A4 to form tight spherical nanoparticles, thereby further facilitating RTP emission (-12 times) in addition to a prolonged lifetime (i.e., 1.80 ms c.f., 50.1 µs). Interestingly, following cascaded assembly with a photocontrolled energy acceptor (i.e., SP), the efficient light-driven RTP energy transfer occurs when SP is transformed to its fluorescent merocyanine (MC) state. Ultimately, this endows the final system with an excellent RTP-fluorescence photoswitching property accompanied by multicolor tunable long-lived emission. Moreover, this switching process can be reversibly modulated over multiple cycles under alternating UV and visible photoirradiation. Finally, the prepared switch is successfully applied to photocontrolled multicolor cell labeling to offer a new approach for the design and fabrication of novel advanced light-responsive RTP materials in aqueous environments. [ABSTRACT FROM AUTHOR]

Room‐temperature phosphorescence (RTP) from polymer carbon dots (PCDs) has attracted great attention for its potential applications in manufacturing anticounterfeit objects and digital encryption. However, most RTP raw materials with good performance are generally toxic, corrosive, and polluting, which will cause safety hazards during use and subsequent processing. Herein, facile, environmental‐friendly polymer carbon dots are prepared by hydrothermal treatment of gelatin and carboxylate (C‐PCDs) for the first time. The RTP of C‐PCDs is yellow emission and the lifetime up to 422 ms, which is three times that of PCDs produced only by gelatin. Then according to transmission electron microscope, atomic force microscopy, Fourier transform infrared, X‐ray photoelectron spectroscopy, gel permeation chromatography characterizations, and comparison of optical properties, it is found that the newly CONH formed by introduced carboxylate and free amino produced in the hydrolysis has an inhibitory effect on the hydrolysis of amide bonds contained in gelatin and deamination to a certain extent, which will be thought about more n‐π* transition from CO enhancing the conversion for triplet excitons. Moreover, the C‐PCDs with properties of fluorescence and phosphorescence are confirmed in the potential application of double anticounterfeiting under the excitation of ultraviolet lamps. [ABSTRACT FROM AUTHOR]

Transforming carbon dots (CDs) fluorescent materials into smart materials with complex functions is a topic of great interest to nanoscience. However, designing CDs with regulating fluorescence/phosphorescence that can be visually monitored with the environment changes in real‐time remains a challenge. Here, a very simple strategy, one‐step solvent‐free catalytic assistant strategy, which is low cost, facile, environment‐friendly, and high throughput, is put forward. Hydrogen bond is used to manipulate nanostructure of CDs, and the obtained carbon dots (M‐CDs) show a series of attractive properties including matrix‐free room‐temperature phosphorescence, time‐dependent fluorescence, and near‐infrared emissive characteristics. Different from the traditional aggregation caused quenching or aggregation‐induced emission fluorescent materials, M‐CDs exhibit unprecedented and unique dispersion induced redshift fluorescence phenomenon, promoting the studies of fluorescence from static to dynamic. The causes of this phenomenon are further analyzed in detail. As a kind of intelligent fluorescent materials, this new designed CDs greatly enrich the basic recognition of CDs by illustrating the relationship between redshift fluorescence behaviors and the dispersion states, and may provide with an opportunity for solid‐state fluorescent materials, anti‐counterfeiting, cellular imaging, and hopefully many others. [ABSTRACT FROM AUTHOR]

Organic room-temperature phosphorescence (RTP) shows high potential in optical fields, and self-assembly method via various non-covalent interactions is one facile and efficient way to enhance RTP performance. Herein, we investigated the RTP behaviors of three imidazole-based polymer films containing imidazole, methyl imidazolium, and benzyl imidazolium moieties, respectively. Their RTP behaviors and chemical structures were compared and discussed to explore the underlying structure-properties relationships. Owing to plenty of hydrogen bonds of polyacrylamide matrix to lock phosphors, imidazolium-based films gave an obvious green RTP due to cations and iodine anions-enhanced intersystem crossing. The blue RTP signals of imidazole-containing film was aroused by coordination with Zn2+ ions due to crosslinking and heavy atom effects. Moreover, the RTP performance of benzyl imidazolium-based film was remarkably improved by host-guest complexation with cucurbit[7]uril, showing a long lifetime up to 230.6 ms. By utilizing the difference in their RTP lifetimes, information encryption application was successfully achieved as a proof of concept. [Display omitted] [ABSTRACT FROM AUTHOR]

Fluorescence and phosphorescence are known as two kinds of fundamental optical signals, which have been used for myriad applications. To date, simultaneous activation of stable fluorescence and long‐lived room‐temperature phosphorescence (RTP) emission in the aqueous phase remains a big challenge. We prepare zinc‐doped silica nanospheres (Zn@SiNSs) with fluorescence and RTP properties using a facile hydrothermal synthetic strategy. For the as‐prepared Zn@SiNSs, the recombination of electrons and holes in defects and defect‐stabilized excitons derived from oxygen vacancy/C=N bonds lead to the production of stable fluorescence and long‐lived RTP (emission lasting for ≈9 s, quantum yield (QY): ≈33.6 %, RTP lifetime: ≈236 ms). The internal Si−O bonded networks and hydrophilic surface in Zn@SiNSs can reduce nonradiative decay to form self‐protective RTP, and also provide high water solubility, excellent pH‐ and photostability. [ABSTRACT FROM AUTHOR]

Angular sulfide and sulfone bridged cis-benzothiazinophenothiazine derivatives with phenyl and benzoyl attached at the amino positions were synthesized and characterized. Crystallographic analyses revealed their twisted structures. The phenyl substituted sulfone bridged benzothiazinophenothiazine demonstrated bright fluorescence emission in both solution and crystalline state. The benzoyl substituted benzothiazinophenothiazine and the sulfone derivatives showed room-temperature phosphorescence in the crystalline states. The electron-rich phenyl substituted cis-benzothiazinophenothiazine compound could be chemically oxidized to monocation and dication with gradually planarized structures depending on the oxidation states. [ABSTRACT FROM AUTHOR]

Developing metal-free and long lifetime room-temperature phosphorescence (RTP) materials has received tremendous interest due to their numerous potential applications, of which stable triplet-excited state is the core challenge. Here, boron carbon oxynitride (BCNO) dots, emitting stable blue fluorescence and green RTP, are reported for the first time. The obtained BCNO dots exhibit an unexpected ultralong RTP lifetime of 1.57 s, lasting over 8 s to naked eyes. The effective doping of carbon and oxygen elements in boron nitride (BN) actually provides a small energy gap between singlet and triplet states, facilitating the intersystem crossing (ISC) and populating of triplet excitons. The formation of compact cores via crystallization and effective inter-/intra-dot hydrogen bonds further stabilizes the excited triplet states and reduces quenching of RTP by oxygen at room temperature. Based on the water-soluble feature of BCNO dots, a novel advanced security ink is developed toward anti-counterfeiting tag and confidential information encryption. This study extends BCNO dots to rarely exploited phosphorescence fields and also provides a facile strategy to prepare ultralong lifetime metal-free RTP materials. [ABSTRACT FROM AUTHOR]

A D‐A‐D′ type pure organic molecule, named ODFRCZ, has unique triple‐emission character covering fluorescence, phosphorescence, and delayed fluorescence (DF). The phosphorescence of ODFRCZ has a rather long lifetime of about 350 ms at room temperature. One dimer of ODFRCZ with enhanced parallel molecular packing acts more effectively to prompt ISC processes, which further generates room‐temperature phosphorescence (RTP), owing to the larger transition dipole moment and closer energy level between S1 and Tn. ODFRCZ is a rare example of an organic RTP molecule that shows dual‐stimuli responsiveness of dual‐mode mechanochromism (fluorescence red‐shift and RTP/DF on‐off switch) and reversible crystal‐state photochromism. This work may broaden the knowledge for stimuli‐responsive RTP organic molecules and lay the foundation for their wide‐scale applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • A CDs@LP with fluorescence and ultra-long (lifetime of 1.33 s) RTP were prepared. • The dual-responsive probe provide a novel strategy for accurate OTC detection. • Fluorescence and RTP test strip was successfully used to analyze OTC. • The dual-signal probe exhibit low LOD and good recovery rate in actual water samples. Dual-responsive probes emitting both fluorescence and phosphorescence signals are greatly advantageous to sensing. Here, we present a carbon dots-based luminophore (CDs@LP) with blue fluorescence and ultra-long yellow room-temperature phosphorescence (RTP) with lifetime of 1.33 s (that was visible to the naked eye for ∼ 13 s) for ratiometric detection of oxytetracycline (OTC). The CDs@LP was prepared by molten salt method through one-step treatment of 2, 6-diaminopyridine, KNO 3 , MgCl 2 , and KH 2 PO 4. Upon the addition of OTC into CDs@LP aqueous solution, the fluorescence at 386 nm and RTP at 538 nm of CDs@LP were quenched as a result of the inner filter effect (IEF), while the fluorescence at 522 nm of OTC steadily enhanced due to the molecular restriction through the formation of OTC-Mg2+ complexes. Both fluorescence and RTP signals have excellent linear relationships with OTC concentration. The CDs@LP had a low detection limit of 3.2 nM (fluorescence) and 0.27 μM (phosphorescence), which also exhibited satisfactory selectivity and anti-interference performance towards other antibiotics. Moreover, the CDs@LP was successfully loaded on a filter paper and used for OTC sensing. Thus, it is a promising tool for OTC detection and can act as a foundation for producing dual-signal sensing tools. [ABSTRACT FROM AUTHOR]

Fluorescent and room-temperature phosphorescent (RTP) materials are widely used in bioimaging, chemical sensing, optoelectronics and encryption. Here, a series of single-component dual-emissive waterborne polyurethanes (WPUs) with both fluorescence and room-temperature phosphorescence were synthesized. Dye without halogen atom incorporated into WPUs can only exhibit fluorescence due to poor spin-orbit coupling. When bromine atom is introduced into dye, we found that WPUs can emit both fluorescence and room-temperature phosphorescence with lifetimes up to milliseconds because of enhanced spin-orbit coupling. Moreover, with an increase in dye concentrations in WPUs, excimers are formed due to the aggregation effect, and may promote communication between singlet and triplet states. At different dye concentrations, structural, thermal, and luminescent properties serve as the main focus. [ABSTRACT FROM AUTHOR]

The monitoring of photosensitizers (PSs) and tissue oxygen are both important in photodynamic therapy. PSs can be monitored by the magnetic resonance imaging of Gd-porphyrins. Dissolved oxygen measurements based on hematoporphyrin monomethyl ether coordinated to trivalent gadolinium ion (Gd-HMME) and free base HMME were studied for determining the PSs and tissue oxygen concentrations simultaneously. Fluorescence of HMME is independent of oxygen, while phosphorescence of Gd-HMME is observed to be sensitive to oxygen. Ratiometric oxygen sensing based on Gd-HMME phosphorescence and HMME fluorescence was proposed, and the relationship between the ratio of phosphorescence to fluorescence and oxygen concentration was found to be linear. The relative uncertainty of the measured values for oxygen concentration reaches its minimum when the fluorescence intensity equals the phosphorescence intensity because of the obtainment of high signal-to-noise ratio for them. The uncertainty of the measured values for 62.5 μM oxygen was 1.2 μM, which indicates that the measurement range and precision of the oxygen measurement system we proposed can reach 0–300 μM and 1.9%, respectively. For detection of oxygen at different concentrations, the measurement uncertainty can be decreased by using HMME and Gd-HMME with suitable concentration ratio to equalize the fluorescence and phosphorescence intensities. Our results indicate that the ratiometric oxygen detection method can fulfill the requirement for tissue oxygen evaluation. [ABSTRACT FROM AUTHOR]

The non-radiative transition of triplet excitons limits the emission of room-temperature phosphorescence (RTP). In this paper, F, N co-doped carbon nanomaterials including carbon dot solutions (L -CDs) with cyan fluorescence and solid-state carbon nanowires (S-CNWs) with yellow fluorescence were successfully prepared by the one-pot hydrothermal method. Interestingly, L -CDs@PVA composites with green RTP were obtained by mixing L -CDs with PVA. The RTP production was attributed to F, N related heteroatomic functional groups on the surface of L -CDs. The C-N, C N bonds form lone electron pairs, which promote the electron transition from n→π∗. The F doping reduces the energy gap from the single to the triplet state, which facilitates the inter-system crossing (ISC) process and increases the radiative transition of the triplet exciton to produce RTP. In addition, PVA forms abundant hydrogen bonds with L -CDs to effectively immobilize the luminescence center and isolate atmospheric oxygen, so that L -CDs@PVA has stable phosphorescence emission at room temperature and this phosphorescence is reversible in dry and wet states. In contrast, S-CNWs displayed solid-state yellow fluorescence, but no phosphorescence even though doped into the PVA matrix (S-CNWs@PVA). Therefore, based on the different characteristics of fluorescence and phosphorescence of L -CDs and S-CNWs, a complex, multi-level information encryption method is proposed and the potential applications of S-CNWs powder for fingerprint recording are explored. • F, N co-doped carbon dots (L -CDs) and carbon nanowires (S-CNWs) were prepared. • L -CDs@PVA and S-CNWs have RTP and solid-state fluorescence respectively. • L -CDs and S-CNWs have potential application for multi-level information encryption. [ABSTRACT FROM AUTHOR]

Due to the high photoluminescence quantum yield (PLQY) and multiple-colored emissions by adjusting their composition and structures, organic-inorganic hybrid metal halides (MHs) have become promising emitters for next-generation light emitting and displays. When separate inorganic metal halides by larger organic cations in crystals, multiple low-dimensional MHs (LDMHs) at the molecular level can be constructed. These LDMHs have been widely reported to exhibit excellent photoluminescence properties which stems from radiative recombination of self-trapped excitons (STEs). Recently, efficient triplet state emission including room-temperature phosphorescence (RTP) originated from organic cations triplet states is also demonstrated in LDMHs, opening a new field for the development of phosphorescence emitters. Herein, we summarize and discuss the new progress in triplet state emission in LDMHs for a better understanding the RTP development of LDMHs for their versatile display applications. [Display omitted] • Recent reports on efficient RTP in LDMHs. • The key to achieve efficient RTP in LDMHs. • The latest application of RTP of LDMH materials. [ABSTRACT FROM AUTHOR]

Abstract: Very simple and highly sensitive methods are presented for the determination of benzo[a]pyrene, one of the most carcinogenic polycyclic aromatic hydrocarbons (PAHs). The approaches are based on solid-phase extraction of the analyte on a nylon membrane via a syringe procedure, and its fluorescent or phosphorescent determination on the solid surface. While the native fluorescence of benzo[a]pyrene retained on a nylon surface is measured directly, room-temperature phosphorescence is induced by spotting a few microlitres of thallium(I) nitrate solution on the surface (heavy-atom effect). An enhancement of the phosphorescence signal was corroborated when the measurements were carried under a nitrogen atmosphere. The analytical figures of merit obtained under the best experimental conditions demonstrate the capability of detecting benzo[a]pyrene at a sub-parts-per-trillion (sub-ngL−1) level. The potential interference from other common PAHs and also from different metal ions was studied. The feasibility of determining benzo[a]pyrene in real samples was successfully evaluated through the analysis of spiked tap, underground and mineral water samples of different origins. Recoveries obtained from spiked river waters were successfully compared with those provided by a reference method, through rigorous statistical analysis. [Copyright &y& Elsevier]

Room-temperature phosphorescence (RTP) has been exploited for analytical research for over 30 years now due to the widespread recognition of its unique properties as a selective and sensitive technique, complementary to fluorescence. Recent years have seen the awakening of medical, geological, industrial, and technological interest in its application. The trend continues, driven by the achievements that have already been made and the promise of future achievements. This review attempts to cover specifically emerging applications of RTP in areas such as medicine, geological dating, forensics, and technology, illustrating the advantages that can be derived from the use of the technique and stressing its potential for novel applications. [ABSTRACT FROM AUTHOR]

A detailed analysis of luminescence properties of humic substances and fulvic acids extracted from peat soil is carried out for the first time. Their fluorescence excitation and emission spectra, fluorescence lifetimes, phosphorescence excitation and emission spectra, and phosphorescence lifetimes at room temperature are investigated. The nature of chromophores of humic substances is discussed. [ABSTRACT FROM AUTHOR]

The development of metal‐free room‐temperature phosphorescent (RTP) and white‐light‐emitting supramolecular materials is significant for artificial soft materials. Herein, a polypseudorotaxane xerogel is fabricated by threading a linear brominated aromatic aldehyde polymer into α‐cyclodextrin cavities. The xerogel can be excited to produce not only RTP signals based on the xerogel network structure's strong restriction of phosphor vibrations and suppression of the nonradiative relaxation process but also white‐light emission at room temperature. Notably, the polypseudorotaxane system possesses excellent fluorescence–phosphorescence dual emission properties and is capable of reversible photoluminescence switching between blue fluorescence emission and white‐light emission in the presence and absence of water. [ABSTRACT FROM AUTHOR]