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In the present study, we investigated the photoluminescence (PL) and scintillation properties of Sm:CaHfO3. All Sm:CaHfO3 samples showed multiple PL emission peaks due to the 4f-4f transitions of Sm3+. Additionally, the PL quantum yield of 0.5% Sm:CaHfO3 was 62.8% under excitation at 410 nm, and the value was the highest among the samples. Under X-ray irradiation, all the samples showed emission peaks due to the 4f-4f transitions of Sm3+. Afterglow levels at 20 ms after 2 ms X-ray irradiation were 6000-22000 ppm. [ABSTRACT FROM AUTHOR]

The radioluminescence and dose rate response of LaMgAl11O19 doped with rare earth single crystals were investigated. All the samples showed emission peaks at wavelengths longer than 800 nm corresponding to doped trivalent rare-earth ions. Among the prepared samples, the Nddoped sample showed the best lower detection limit of 1.6 mGy/h, enabling highly sensitive dose measurement. [ABSTRACT FROM AUTHOR]

Eu2+ and Ln3+ (Ln3+ = Nd3+, Dy3+, Ho3+, Tm3+, Yb3+) co-doped Sr2Al2SiO7 green-phosphors were synthesized via high temperature solid state method. The XRD analysis proved that the obtained phosphors are all pure-phased. To investigate the luminescent properties, the analysis of fluorescence, afterglow luminescence, photo-stimulated luminescence and diffuse reflection spectrum were conducted. It is evident that the central positions of excitation and emission spectra remained unchanged. However, the intensity and decay time of the afterglow and photo-stimulated luminescence of Eu2+ were tunable through doping with various Ln3+ ions. Among them, Eu2+ and Tm3+ co-doped Sr2Al2SiO7 exhibits excellent photo-stimulated luminescence properties. Moreover, the results from thermoluminescence (TL) measurements suggest that the introduction of Tm3+ doping induces deeper traps. Additionally, afterglow decay and TL curves were assessed, highlighting the exceptional phosphorescent properties exhibited by the present phosphors. [ABSTRACT FROM AUTHOR]

Advanced optical information encryption usually relies on the integration of multicolor, stimulus‐responsive, and afterglow luminescence. However, achieving these simultaneously within a single‐phase system has posed challenges, complicating the design process. In this study, an advanced 3D information encryption strategy is presented based on undoped and alloyed Cs₂CdCl₄, encrypted through three distinct channels: emission wavelength, water stimulation, and afterglow time. Specifically, Mn2+, Sb3+, and Ag+ doped Cs₂CdCl₄ single crystals are successfully synthesized via a modified hydrothermal method, which exhibit bright orange, green, and blue emissions, respectively. Decryption of specific information can be achieved by employing corresponding narrowband filters. Furthermore, the Cs₂CdCl₄ system demonstrates hydrochromism, attributed to water‐induced sequential phase transitions. Upon water treatment, the 2D Cs₂CdCl₄ will undergo a phase transition to Cs3Cd2Cl7, and finally to cubic CsCdCl3. Interestingly, the resultant CsCdCl3 exhibits pronounced afterglow, originating from the triplet emission of Cd ions. Leveraging these unique properties, a highly secure and adjustable 3D encrypted quick response code is designed. The encrypted information is encoded in coordinates, and decrypted information can be retrieved in both compressed and decompressed modes as required. These findings pave the way for the development of novel smart photonic materials and multimodal optical information encryption. [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]

Miniaturization of organic afterglow materials has shown promising application in biomedical and other areas. Current technologies, such as nanoprecipitation, mechanical treatment, and emulsion polymerization, lack the capability of facile control on the morphology and dimension of the miniaturized organic afterglow materials. Here we report the fabrication of organic afterglow nanostructures via block copolymer self‐assembly at room temperature. The fabrication is based on two‐component design strategy where hydrophobic luminescent emitters with small rate constants of phosphorescence decay or reverse intersystem crossing are designed as the first component. Amphiphilic block copolymers that can form spherical core‐shell micelles and worm‐like micelles with glassy hydrophobic cores are used as the second component. Upon addition of water into a dimethylformamide solution that contains the two components, the amphiphilic block copolymers self‐assemble into well‐defined nanostructures and accommodate the hydrophobic luminescent emitters in nanostructure's hydrophobic cores. After switching to pure water by dialysis, room‐temperature afterglow nanostructures have been obtained because of the excellent protection of organic triplets by the glassy hydrophobic cores. The afterglow nanostructures exhibit intriguing afterglow mechanism modulated by the types of luminescent emitters, controlled dimensions and morphologies by the structural parameters of the block copolymers. [ABSTRACT FROM AUTHOR]

The paper examines afterglow spectra of chlorine–xenon mixtures excited by XeCl laser pulses (308 nm). The dependence of the spectra on the composition and pressure of the mixtures is shown. The mixtures are compared with the total luminescence spectra measured under similar conditions. The time characteristics of excitation and luminescence pulses are presented. [ABSTRACT FROM AUTHOR]

Organic afterglow panels show promising applications in display and information anti‐counterfeiting. Like other panels, organic afterglow panels are susceptible to contamination when used, which can affect their aesthetics and clarity. Here, a kind of visible‐light‐excitable anti‐smudge organic afterglow panels based on a dopant‐matrix strategy and easily prepared through the UV light‐curing method is reported. The phosphorescence lifetime of the panel is up to 9.45 s with an afterglow duration longer than 100 s. Moreover, the transparent panels with low dynamic friction (0.129), large water contact angle (108°) and oleic acid contact angle (77°), display high performance of anti‐smudge, water and oil repellency, and removability of fingerprints, avoiding the influence of ink or sewage on its aesthetics and clarity. This study will expand the pathways for practical applications of afterglow materials. [ABSTRACT FROM AUTHOR]

Unlocking the afterglow properties of the fluorescence molecules at room temperature is an urgent challenge. Herein, inks prepared with dimethyl terephthalate (DTT) and carbazole (Cz) analogs with heteroatom (C, S, and O) substituents on the N as host and guest molecules can be directly sprayed onto different substrates to unlock the excitation‐wavelength dependent (Ex‐De) afterglow characteristics of the guest compound. Additionally, with the increase in the number of lone pair electrons, spin‐orbit coupling (SOC) increases, resulting in a longer afterglow duration lasting up to 4.5 s with Φp>27%. Theory calculations and experiments indicate that the afterglow originated from the interactions between the host and guest molecules restricting the non‐radiative transition of the triplet excitons. Different Ex (with watershed at 310 nm) lead to the variation in the conformation of the S0DTT and S1DTT, which in turn affects the strength of host‐guest interactions and contributes to the Ex‐De characteristics. Benefiting from facile preparation, substrate‐independent applicability, and Ex‐De characteristics, the afterglow samples are demonstrated for applications in multilevel information security fields. This work proposes a general strategy for unlocking the afterglow emission of traditional molecules, which is valuable for the discovery of high‐performance afterglow materials in the future. [ABSTRACT FROM AUTHOR]

Luminescence metal–organic materials (MOMs) are widely used as probes for detection. However, most of such probes are based on fluorescence and work in either turn‐off or turn‐on mode. In contrast, long‐lived (>10 ms) probes (LLPs) with recovery response to analyte are quite rare. Herein "solvation complex" strategy is used to prepare two new afterglow complexes with multiple coordinated solvents, trans‐complex 1 with both delayed fluorescence (DF) and room temperature phosphorescence (RTP), and cis‐complex 2 with RTP. Remarkably, they can serve as selective and recovery LLPs for l‐Arginine detection, with limit of detection down to 1.0 × 10−7 M. In addition, heating/fumigation can induce reversible arousal/silence of their afterglow, while H2O/DMSO vapor fumigation causes reversible crystalline‐to‐crystalline transformation between them. Detailed mechanism studies reveal that the change in coordinated solvent, including loss/acquisition, exchange, or replacement, plays a key role in such afterglow multi‐stimuli‐responsive properties. This work not only shows the potential of such long‐lived luminescence complex for recovery detection, but also reveals the unique advantages of solvation complex in the preparation of afterglow multi‐stimuli‐responsive materials [ABSTRACT FROM AUTHOR]

Objective: The green synthesis of Tin(IV) oxide (SnO2): Gold (Au) nanoparticles (NPs) using Teucrium polium medicinal plant extract was investigated, and the NPs were characterized and tested as photosensitizers to produce reactive oxygen species (ROS). Methods: The cytotoxic effect on C26 cells was investigated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) technique. The results showed their toxicity in a dose-dependent manner. The green synthesis of SnO2:Au NPs was achieved for the first time using an extract of T. polium medicinal plant as a reducing and stabilizing agent. The produced NPs were examined for their application in photodynamic therapy (PDT) for cancer. Results: Methylene blue and anthracene were used to confirm that the photosensitizer could produce ROS when excited with UVA radiation. The anticancer activity of SnO2:Au was investigated in vitro using the C26 cell line and an MTT assay, showing that PDT with SnO2:Au NPs could inhibit cancer cell proliferation. Conclusions: The significant afterglow of the SnO2:Au NPs could cause the generation of ROS to continue several minutes after switching off the light source. [ABSTRACT FROM AUTHOR]

Organic photoresponsive materials, which change their physical properties upon irradiation with light, are attracting tremendous scientific attention, as they offer a flexible and sustainable platform for developing various optoelectronic devices. In this work, photoinduced magnetization switching in two carbazole‐functionalized organic molecules, (9H‐carbazol‐9‐yl)(4‐chlorophenyl)methanone (ClPhCz) and (9H‐carbazol‐9‐yl)(2,4‐dichlorophenyl)methanone (DClPhCz) is reported for the first time. It was found that stabilization of the triplet excited state in those molecules is long enough for a net change in magnetic moment to be detected with a SQUID magnetometer. The change in magnetic moment upon excitation with a blue light laser was larger in ClPhCz, remaining high upon repeating the photoirradiation. In contrast, DClPhCz exhibited a smaller magnetic response, which gradually decreased upon repeating the experiment. [ABSTRACT FROM AUTHOR]

Comprehensive research into afterglow emission in the near‐infrared (NIR) region of carbon dots (CDs) is currently lacking. In this study, highly efficient multicolor CDs are synthesized with fluorescence from blue to NIR using Rhodamine 6G. Boron oxide (B2O3) is employed as a matrix for encapsulating and confining the CDs, inhibiting triplet exciton quenching. Furthermore, structural rigidity is enhanced due to the formation of carbon‐boron (C─B) covalent bonds between CDs and B2O3, achieving tunable afterglow emission ranging from 463 to 722 nm with lifetimes up to 801 ms. The green–yellow afterglow composite exhibits an impressive quantum yield up to 37.67% while demonstrating thermally activated delayed fluorescence (TADF). Thus, this composite is coated onto a blue alternating‐current light‐emitting diode (BAC‐LED) to fabricate a white AC‐LED, which is successfully prepared with Commission Internationale de L'Eclairage (CIE) at coordinates of (0.32, 0.34), accompanied by the color rendering index (CRI) reaching 81.1. The bright afterglow compensates for zero‐point flickering in the BAC‐LED, resulting in stable and gentle emission. The potential applications of these luminescent materials in optoelectronic devices are undoubtedly widened by this remarkable advancement. [ABSTRACT FROM AUTHOR]

Despite recent advancements in inorganic and organic phosphors, creating monodisperse afterglow nanocomposites (NCs) remains challenging due to the complexities of wet chemistry synthesis. Inspired by nanoinclusions in opal, we introduce a novel SiO2‐mediated carbon dot (CD) doping method for fabricating monodisperse, multifunctional afterglow NCs. This method involves growing a SiO2 shell matrix on monodisperse nanoparticles (NPs) and doping CDs into the SiO2 shell under hydrothermal conditions. Our approach preserves the monodispersity of the parent NP@SiO2 NCs while activating a green afterglow in the doped CDs with an impressive lifetime of 1.26 s. Additionally, this method is highly versatile, allowing for various core and dopant combinations to finely tune the afterglow through core‐to‐CD or CD‐to‐dye energy transfer. Our findings significantly enhance the potential of SiO2 coatings, transforming them from merely enhancing the biocompatibility of NCs to serving as a versatile matrix for emitters, facilitating afterglow generation and paving the way for new applications. [ABSTRACT FROM AUTHOR]

Persistent luminescent materials are those which can store an amount of energy locally and release it slowly in the form of light. In this work, persistent luminescent nanoparticles (PLNPs) were synthesized and incorporated into polypropylene (PP) filaments at various loading percentages. We investigated the optical properties of both the as-prepared PLNPs and the PLNP-loaded filaments, focusing on any changes resulting from the integration into the filaments. Specifically, visible and near-infrared spectroscopy were used to analyze the emission, excitation, and persistent luminescence of the PLNPs and PLNP-loaded filaments. The tensile properties of the extruded filaments were also investigated through breaking tenacity, elongation at break, Young's modulus, and secant modulus. All PLNP-loaded filaments were shown to exhibit persistent luminescence when exposed to ultraviolet light. While there were no significant changes in the elongation at break or Young's modulus for the loading percentages tested, there was a slight increase in breaking tenacity and a decrease in the secant modulus. Finally, the filaments were shown to maintain their optical properties and persistent luminescence even after abrasion testing used to simulate the normal wear and tear that fabric experiences during use. These results show that PLNPs can be successfully incorporated into filaments which can be used in fabrics and will maintain the persistent luminescent properties. [ABSTRACT FROM AUTHOR]

A study was conducted to examine the recombination processes in persistent phosphor Mg3Y2Ge3O12:Tb3+ garnet at low temperatures. Photoluminescence (PL), recombination luminescence (RL), electron paramagnetic resonance (EPR), and EPR detected by PL or RL were measured.In samples with low Tb3+ concentration, a broad PL and RL band around 400–450 nm and characteristic Tb3+ lines were observed. However, in samples with high Tb3+ concentration, only Tb3+ lines were present. Both the broad-band and the line components exhibit long-lasting tunneling luminescence with hyperbolic decay. After 263 nm UV irradiation signals of intrinsic electron (F-type) and hole (V-type) trapping centres were observed in the EPR spectra. Such signals were also observed in RL-detected EPR spectra, indicating that the broad RL band at low Tb3+ concentrations originates from tunneling recombination between these intrinsic traps. At high Tb3+ concentrations, the RL-EPR spectrum was not observed, suggesting that intrinsic electron and Tb-related hole trapping centres probably participate in the tunneling recombination.

Abstract Classic psychedelics and MDMA have a colorful history of recreational use, and both have recently been re-evaluated as tools for the treatment of psychiatric disorders. Several studies have been carried out to assess potential long-term effects of a regular use on cognition, delivering distinct results for psychedelics and MDMA. However, to date knowledge is scarce on cognitive performance during acute effects of those substances. In this systematic review and meta-analysis, we investigate how cognitive functioning is affected by psychedelics and MDMA during the acute drug effects and the sub-acute (“afterglow”) window. Our quantitative analyses suggest that acute cognitive performance is differentially affected by psychedelics when compared to MDMA: psychedelics impair attention and executive function, whereas MDMA primarily affects memory, leaving executive functions and attention unaffected. Our qualitative analyses reveal that executive functioning and creativity may be increased during a window of at least 24 h after the acute effects of psychedelics have subsided, whereas no such results have been observed for MDMA. Our findings may contribute to inform recommendations on harm reduction for recreational settings and to help fostering differential approaches for the use of psychedelics and MDMA within a therapeutic framework.

Gadolinium pyrosilicate (GPS, Gd2Si2O7) single crystals with different doping concentrations of Tb (0.1–2.0 mol%) are successfully fabricated using the floating-zone technique. In this work, the dependence of Tb-doping concentration on the photoluminescence (PL) and scintillation properties of Tb-doped GPS (Tb:GPS) has been investigated. The PL emission contour graph shows multiple emissions, with the strongest emissions at 378 nm for 0.1% and 0.5% Tb-doping and 544 nm for 1.0% and 2.0% Tb-doping, corresponding to Tb3+ 4f-4f transitions. The PL lifetimes of the specimens range from 4.89 to 5.22 ms. The scintillation spectra exhibit comparable wavelength and intensity trends to the PL emission. The scintillation lifetimes of the specimens range from 2.41 to 3.88 ms. The Tb:GPS specimens demonstrate a relatively excessive afterglow level, with Af20 values ranging from 1640 to 7250 ppm and Af40 values ranging from 136 to 362 ppm. Using recently developed pulse height measurement for millisecond decay scintillators, under excitation at 662 keV γ-rays, the 1.0% Tb:GPS specimen exhibits the highest scintillation light yield among all other specimens at 95,600 ph/MeV, making Tb:GPS one of the highest light yield oxide scintillators. [ABSTRACT FROM AUTHOR]

Infrared (IR) luminosity of lightning channel in the 3–5 μm range usually persisted throughout the entire interstroke interval, which is in contrast to the simultaneously recorded visible (0.4–0.8 μm) luminosity that always decayed to an undetectable level prior to a subsequent return stroke pulse. A longer visible luminosity period at the end of flash tended to be associated with a longer IR afterglow period following the decay of visible luminosity (and by inference current) to an undetectable level. At the end of flash, the IR luminosity persisted up to about 1 s, and the median IR afterglow duration was a factor of 10 longer than the median visible luminosity duration. The IR luminosity often exhibited a hump when the visible luminosity was monotonically decaying or undetectable, with the corresponding channel temperature being likely around 3400 K. Plain Language Summary: Lightning is usually imaged in the visible (0.4–0.8 μm) range, although it also produces significant infrared (IR) emission. In this study, we compare, for the first time, the medium‐to‐far (3–5 μm) IR luminosity of lightning channels with the simultaneously recorded visible luminosity. The key findings include the persistent nature of IR luminosity throughout interstroke intervals, which is in contrast to visible luminosity that always decayed to an undetectable level before the following return‐stroke onset. After the last stroke, IR luminosity persisted much longer than visible luminosity. The IR luminosity often exhibited a hump when visible luminosity was monotonically decreasing or already undetectable. We inferred that the IR hump, occurring when the channel temperature decreases to a few thousand Kelvin, is associated with enhanced IR emission from nitric oxide molecules whose concentration is expected to be maximum around 3400 K. We also examined a number of factors influencing IR afterglow duration, such as the number of preceding strokes, return‐stroke peak current, and the occurrence of M‐components. This study contributes to the very limited literature on the IR emission from lightning and provides new insights into the dynamics of lightning channel cooling process. Key Points: In contrast to the visible, infrared (IR) channel luminosity between strokes usually persisted through the following return‐stroke onsetIR luminosity profile often exhibited an increase (hump) when the visible luminosity was monotonically decaying or undetectableAt the end of flash, IR luminosity persisted up to ∼1 s and its median duration was a factor of 10 longer than its visible counterpart [ABSTRACT FROM AUTHOR]

All‐inorganic metal halides with afterglow emission have attracted increasing attention due to their significantly longer afterglow duration and higher stability compared to their organic–inorganic hybrid counterparts. However, their afterglow colors have not yet reached the blue spectral region. Here, we report all‐inorganic copper‐doped Rb2AgBr3 single crystals with ultralong blue afterglow (>300 s) by modulating defect states through doping engineering. The introduction of copper(I) ions into Rb2AgBr3 facilitates the formation of bromine vacancies, thus increasing the density of trap states available for charge storage and enabling bright, persistent emission after ceasing the excitation. Moreover, cascade energy transfer between distinct emissive centers in the crystals results in ultra‐broadband photoluminescence, not only covering the whole white light with near‐unity quantum yield but also extending into the near‐infrared region. This 'cocktail' of exotic light‐emission properties, in conjunction with the excellent stability of copper‐doped Rb2AgBr3 crystals, allowed us to demonstrate their implementation to solid‐state lighting, night vision, and intelligent anti‐counterfeiting. [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]

This paper deals with experimental studies of ionization waves igniting the breakdown in long discharge tubes in neon at low pressures. Ionization waves were produced by rectangular voltage pulses applied to the high-voltage electrode of the discharge tube. Our research focused on concentration measurements of neon excited atoms at the metastable 1s5(3P2) level after the ionization wave passage and the breakdown termination. We also found the characteristic decay times of these states and the most significant elementary processes responsible for metastable atom deactivation.

Mn ions in different valence states can emit light of different colors in an octahedral coordination environment, which is conducive to the development of a single matrix with multi-color luminescence and applications in the field of anti-counterfeiting. The dual mode multi-color luminescent material CaSb 2 O 6 : Mn has been successfully synthesized using a single Mn source in the atmosphere. The CaSb 2 O 6 matrix itself can also absorb 285 nm UV light, emit blue light, and show a long afterglow phenomenon. Both Mn4+ and Mn2+ ions will appear in the [SbO 6 ] octahedra, whether the Mn source adopts MnCO 3 or MnO 2. The Mn4+ ion exhibits red emission upon UV excitation at 347 nm. The Mn2+ ion can emit a bright green light at 285 nm excitation while exhibiting a long afterglow phenomenon. In this study, the Mn2+ doped octahedron showed unique green emission and broadens the range of its photoluminescence (PL) wavelength. The performance of the material's long afterglow properties on the digital codes demonstrates its potential for dynamic anti-counterfeiting. [ABSTRACT FROM AUTHOR]

Defects in phosphors affect not only luminescence intensity but also emission peak width, decay time, and afterglow. The green phosphor β -SiAlON:Eu2+ exhibits the green emission of Eu2+ at 520 nm and the blue emission of nitrogen vacancies at 460 nm in time-resolved fluorescence measurements. The decay time of the intrinsic Eu2+ transition is 0.7 μ s, but afterglow is detected from 50 μ s to 0.01 s. This afterglow decay curve is the same for the green emission of Eu2+ and the blue emission of nitrogen vacancies, suggesting that the defect levels of the nitrogen vacancies affect the Eu2+ transition. The afterglow decay curves were analyzed using the formula of the general-order kinetics, 1 + t / τ B − n , where n is the decay power and τ B is the decay time. This equation is generally used when analyzing afterglow on the order of seconds to hours but has not been examined systematically applied in samples with different concentrations of Eu2+ and temperatures on the order of nanoseconds to milliseconds. The decay power n is approximately 1 for all Eu2+ concentrations (x = 0.001–0.3) and undoped β -SiAlON. The decay time τ B is correlated with the density of the nitrogen vacancies determined by electron spin resonance. Furthermore, the value of n is approximately 1 for 50 μ s to 0.01 s and 0.3 for 1–1000 s. Thus, the luminescence mechanism of Eu2+ can be discussed by comparing n and τ B obtained from the decay curves. In addition, several different Eu2+-doped phosphors, namely SrAl2O4:Eu2+, Dy3+, CaAlSiN3:Eu2+, and CaS:Eu2+, Tm3+, are studied. [ABSTRACT FROM AUTHOR]

Traditional roadway lighting is intended to provide safe guidance for drivers and pedestrians, but the large-scale application of roadway lighting has resulted in significant energy consumption and light pollution. However, road markings prepared by luminous coating are a kind of multi-functional road marking that can meet the needs of highway lighting at night and save energy. Here, CaAl2O4:Eu2+,Nd3+,Gd3+ blue long-afterglow phosphor is obtained by the high-temperature solid-state method, and the blue luminescent coating is synthesized by the blending method. The phase composition, microscopic morphology, luminescence properties and water resistance of the phosphor and luminescent coatings are characterized. The best components and processes of the luminescent coating are explored to meet the application of an expressway. Considering the afterglow's performance, the optimal calcination temperature of the phosphor is determined to be 1300 °C. The afterglow of the phosphor can be over 8 h after 2 h of daylight excitation. The addition of 1.25% SiO2 to the luminescent coating improves the uniformity of the components, and the incorporation of 3.5% CaCO3 improves the denseness of the coating. When the coating thickness is 0.8mm, the luminescent coating can achieve the best luminous effect. After 120 h of immersion in water, the afterglow intensity of the luminescent coating reduced to 70% of the original, which has excellent water resistance. The blue luminescent coating with the addition of appropriate amounts of CaCO3 and SiO2 improves the dispersion as well as the densification of the components in the coating to achieve the best luminescent effect. In the Shenyang area, different weather conditions (cloudy, sunny, rainy) have no significant effect on the afterglow performance of the luminescent coatings, all of which can achieve over 5 h of afterglow and are suitable for expressways. [ABSTRACT FROM AUTHOR]

As one of the self‐luminescence imaging approaches that require pre‐illumination instead of real‐time light excitation, afterglow luminescence imaging has attracted increasing enthusiasm to circumvent tissue autofluorescence. In this work, we developed organic afterglow luminescent nanoprobe (nanotorch), which could emit persistent luminescence more than 10 days upon single light excitation. More importantly, the nanotorch could be remote charged by 660 nm light in a non‐invasive manner, which showed great potential for real‐time tracing the location of macrophage cell‐based microrobots. [ABSTRACT FROM AUTHOR]

Afterglow brightness represents one of the most important characteristics in the application of afterglow materials. High molar absorption coefficient, high afterglow efficiency, and long afterglow lifetimes are required to achieve intense afterglow. However, current strategies cannot simultaneously fulfill these requirements due to specific intrinsic problems. Here, based on the understanding of difluoroboron β‐diketonate systems, the manipulation of higher triplet excited states is conceived to selectively enhance intersystem crossing with phosphorescence lifetimes remaining long. Aromatic substrates, which possess specific HOMO levels and T1 levels, are selected for relay synthesis to form difluoroboron β‐diketonate compounds with very close‐lying S1 and T2 levels; according to the energy gap law, such systems exhibit strong intersystem crossing. Upon doping into rigid matrices, the resultant difluoroboron β‐diketonate systems display the brightest ambient afterglow that has ever been observed. [ABSTRACT FROM AUTHOR]

Electrospun glass nanofibers (EGNFs) were prepared to reinforce polyethylene (PE) plastic waste towards the development of photochromic anticounterfeiting patterns and long-persistent photoluminescent materials, such as smart windows and concrete. By physical integration of lanthanide-doped aluminate (LdA) nanoparticles (NPs) into polyethylene plastic reinforced with EGNFs, a transparent lanthanide-doped aluminate nanoparticles (LdANPs)/EGNFs@PE sheet was produced. The colorless EGNFs@PE hybrids became green under ultraviolet (UV) rays and greenish-yellow in a darkened room as proved by CIE Lab and photoluminescence analysis. In the luminescent LdANPs/EGNFs@PE hybrids, the identified photochromism was promptly reversed at low concentrations of LdANPs to designate fluorescence emission. Photoluminescence was maintained with slow reversibility for the high phosphor concentrations to designate afterglow emission. LdANPs exhibit diameters of 5-12 nm, whereas glass nanofibers have diameters of 70-120 nm. The morphologies of LdANPs/EGNFs@PE substrates were studied by energydispersive x-ray spectroscopy (EDX), scanning electron microscopy (SEM), and x-ray fluorescence (XRF). The mechanical properties of the prepared polyethylene plastic were enhanced by reinforcement with glass nanofibers as a roughening agent. The photoluminescent substrates showed markedly improved scratch resistance in comparison to LdANPs-free EGNFs@PE substrate. The obtained luminescence spectra displayed an emission band at 519 nm upon excitation at 365 nm. The results demonstrated that the luminous plastic has improved hydrophobicity and UV shielding upon increasing the LdANPs content. [ABSTRACT FROM AUTHOR]

Ultra‐long room temperature phosphorescence (URTP) materials are extremely promising for applications in organic electronics. Creating materials with controlled photophysics to achieve this, however, is difficult due to the challenges in filling up and stabilizing the sensitive triplet excited states at ambient temperature. Herein, triplet excitons are harvested by an intuitively designed structurally simple organic phosphor in water under ambient conditions by using supramolecular host–guest chemistry with cucurbituril‐7 (CB7) and sodium dodecyl sulphate (SDS), a negatively charged surfactant, with high photoluminescence (PL) quantum yields (PLQYs) (69% and 73% for CB7 and SDS, respectively) and phosphorescence lifetimes (12.52 and 12.42 ms for CB7 and SDS, respectively). A protective polyvinyl alcohol (PVA) film successfully controls the afterglow emission, excited state lifetime as well as PLQY in a single organic phosphor (CzPy24+). While a 1% concentration of CzPy24+ in the PVA film shows blue phosphorescence with 78.82% PLQY having a lifetime of 1.9 s, a 5% of CzPy24+ addition shows a green afterglow with 67.52% PLQY and a lifetime of 1.3 s. Similarly, yellow afterglow is achieved on adding 20% CzPy24+ to the PVA film with a PLQY of 40.88%. The findings are promising and helpful in constructing tunable phosphors for suitable applications. [ABSTRACT FROM AUTHOR]

Phosphorescent glazes are usually used in direction signs of emergency routes. That is why afterglow damping and thermal stability of phosphorescent pigments are the most decisive factors of phosphorescent glazes. This study aims to choose a suitable glaze to enhance the time and intensity of the afterglow. For this reason, the effects of BaO, ZnO, B 2 O 3 , and PbO additives on the afterglow intensity and lifetime of reference industrial glaze containing SrAl 2 O 4 phosphorescent material were investigated. 5, 7, 10, 15, and 20 %wt SrAl 2 O 4 phosphorescence powder was mixed with base industrial glaze to recognize the optimum component. Samples were fired at 1040 °C for 40 min in the same conditions and then were analyzed by photoluminescence spectroscopy. Results showed that increasing the SrAl 2 O 4 proportion increased samples afterglow damping time, and 10 %wt SrAl 2 O 4 was chosen as the optimum amount. Also, BaO is more efficient for increasing the intensity and afterglow lifetime. Moreover, 0.02, 0.03, 0.05, and 0.1 %wt SiC were added to the reference industrial glaze containing 10 %wt SrAl 2 O 4 to investigate the reduction firing conditions on the glaze afterglow. Increasing the SiC ratio up to 0.02 %wt increased the afterglow lifetime from 5 ± 0.4 to 27 ± 1.7 min, but the afterglow intensity was decreased. Despite this, adding 0.03, 0.05, and 0.1 %wt SiC darkened the glaze and reduced the intensity and afterglow lifetime. The sample containing 0.1 %wt SiC did not melt properly, and this sample did not have any afterglow. Furthermore, the temperature required for firing affects the afterglow of the samples. On the other hand, to investigate the effect of temperature, the base industrial glaze containing 10 %wt SrAl 2 O 4 was fired at 1040, 1120, and 1140 °C to determine thermal stability. The sample fired at 1140 °C had almost no phosphorescent afterglow. Also, dilatometry tests at the temperature of 600 °C and hot-stage microscope analysis were performed to determine the linear coefficient of thermal expansion and the melting point of the samples, respectively. The results showed the linear coefficient of thermal expansion of the industrial glaze with 10 %wt SrAl 2 O 4 was 73.3 × 10−7 1/°C, and it could be changed between 58.5 × 10−7 1/°C by adding 10 %wt B 2 O 3 to 73.5 × 10−7 1/°C by adding 10 %wt BaO. The melting point of the pure industrial glaze was 1130 °C, and adding 10 %wt, SrAl 2 O 4 decreased it to 1076 °C. Also, by adding 10 %wt BaO, ZnO, B 2 O 3 , and PbO to phosphorescent glaze, melting point was obtained 1128 °C, 1020 °C, 1030 °C, and 974 °C respectively. The same sample with 0.02 %wt SiC melted at 1154 °C. [Display omitted] • The effects of BaO, ZnO, B 2 O 3 , and PbO additives on the afterglow intensity and lifetime of reference industrial glaze containing SrAl 2 O 4 phosphorescent material were investigated. • The afterglow damping duration increased from 5 to 27 min by controlling the reduction of firing conditions by adding SiC. • The effects of BaO, ZnO, B 2 O 3 , and PbO additives on thermal stability, linear coefficient of thermal expansion, and melting point were investigated. [ABSTRACT FROM AUTHOR]

The accurate thermosensing requires a minimum impact of autofluorescence and light scattering from the samples. In this study, we discovered that commercially available benzene‐1,4‐diboronic acid (BDBA) doped co‐crystals with trimethylolpropane (TMP) exhibit excellent thermochromic dual phosphorescence properties over a wide temperature range from −132 to 40 °C, despite its simple structure that does not have any donor‐acceptor linkage. The dual phosphorescence was consisted of monomeric benzene‐1,4‐diboronate (BDBA ester) and aggregation‐stabilized species. With an increase in temperature, the emission intensity from the monomeric state significantly decreased, whereas that originating from the aggregated state remained almost constant owing to the difference in their thermal stabilities. Further investigation revealed that molecular distortions in singlet excited states enable efficient intersystem crossing, causing efficient phosphorescence from the monomeric state of BDBA ester. [ABSTRACT FROM AUTHOR]

In this work, full‐color and stable white organic afterglow materials with outstanding water, organic solvents, and temperature resistances have been developed for the first time by embedding the selected polycyclic aromatic hydrocarbons into melamine‐formaldehyde polymer via solution polymerization. The afterglow quantum yields and lifetimes of the resulting polymer films were up to 22.7 % and 4.83 s, respectively, under ambient conditions. For the coronene‐doped sample, its afterglow color could be linearly tuned between yellow and blue by adjusting the temperature, and it could still emit an intense blue afterglow with a lifetime of 0.68 s at 440 K. Moreover, the films showed a bright and stable white afterglow at 370 K with a lifetime of 2.80 s and maintained an excellent afterglow performance after soaking in water and organic solvents for more than 150 days. In addition, the application potential of the polymer films in information encryption and anti‐counterfeiting was also demonstrated. [ABSTRACT FROM AUTHOR]

(Gd,Y,Ce)3(YxGa1−x)2GaAl2O12 (GYGAG:Ce) scintillation ceramics with different Y excess, where x = 0.005−0.08, were fabricated by the solid-state reaction method. The effects of stoichiometry on the phase composition, optical quality, and microstructure of GYGAG:Ce ceramics were analyzed. GYGAG:Ce ceramics have a pure garnet phase and obtain good in-line transmittance when x < 0.04, while more Y excess leads to the creation of the secondary phase. The change of x value influences the sintering behavior of the GYGAG:Ce ceramics: The excess of Y works as the self-sintering aid and significantly reduces the sintering temperature of ceramics. When x = 0.01–0.04, the X-ray excited luminescence (XEL) spectra and light yields of GYGAG:Ce ceramics are similar. The fast scintillation decay time and afterglow intensity of GYGAG:Ce ceramics show a slight decrease with increasing x value. Finally, additional 50–500 ppm MgO and 100–500 ppm CaO were introduced to the GYGAG:Ce ceramic with x = 0.04, and both were found to significantly increase the fast scintillation component and reduce the afterglow intensity by two orders of magnitude to 0.01% after X-ray cut-off.