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[Display omitted] Gradually enhancing afterglow under ambient conditions is generated by embedding a typical class of organic luminogens with ingeniousness lying in their architectures into melamine-formaldehyde polymer. Due to effective intramolecular motion resistance, the resulting material exhibits one of the most excellent polymer-based organic afterglow with a phosphorescence quantum yield (Φphos.) up to 38.31% and a lifetime (τphos.) up to 2.73 s. • Gradually enhancing afterglow under ambient conditions is generated. • Effective intramolecular motion resistance is achieved by host–guest doping. • The material exhibits one of the most fabulous polymer-based organic afterglow. • Locking intramolecular conformation contributes to suppressing nonradiative decay. Tackling the challenge of developing ultralong organic phosphorescence (UOP) materials with a high phosphorescence quantum yield (Φ phos.) and an ultralong phosphorescence lifetime (τ phos.) under ambient conditions is urgently needed. Herein, typical organic luminogens with simple chemical structures, namely, triphenylamine (TPA), 9-phenylcarbazole (PCz), and indolo[3,2,1- jk ]carbazole (ICz), are doped into a melamine–formaldehyde (MF) polymer matrix with a compact three-dimensional covalent network to prepare UOP materials, respectively. Both experiments and theoretical calculations suggest that restricting intramolecular motions to suppress the nonradiative decay of triplet excitons plays a critical role in achieving ultralong room-temperature phosphorescence from organic molecules in polymer matrices. The luminophore ICz with a planar and rigid chemical structure, constructed by locking the molecular conformation of TPA via carbon–carbon single bonds, exhibits a bright organic afterglow with a Φ phos. up to 38.31 % and a τ phos. up to 2.73 s in the MF polymer under ambient conditions, representing one of the most excellent polymer-based organic afterglow materials in comprehensive UOP performance. The gradual enhancement in UOP of the resulting luminescent materials has led to their successful use in multi-level anti-counterfeiting. This work provides an effective strategy for developing organic afterglow materials with both high Φ phos. and τ phos. values. [ABSTRACT FROM AUTHOR]

• Long-emission phosphorescence activated by ortho -carboxyl substitution strategy. • Exploration of the multi-color phosphorescent carbon dots. • Tunable LEDs produced by using these carbon dots. While room temperature phosphorescence (RTP) associated with carbon dots (CDs) has been widely achieved, obtaining long-wavelength emission RTP, especially while mitigating the quenching effect of water or dissolved oxygen, remains a challenging yet desirable goal. We synthesized three types of phosphorescent CDs with varying luminescent properties by using three precursors with carboxyls positioned differently. The formation process of these CDs resulted in a well-ordered and compact structure, effectively inhibiting molecular vibrations and reducing non-radiative transitions. Consequently, it successfully prevented the quenching effect of dissolved oxygen on the RTP of CDs in an aqueous environment. Significantly, PA-AIBN synthesized with phthalic acid, rather than iso -phthalic acid and terephthalic acid, exhibited long-wavelength emission RTP, with the phosphorescent emission center reaching as far as 640 nm. To be specific, the ortho -substituted carboxyls played a critical role in boosting the formation of intramolecular hydrogen bonds. Simultaneously, an increase in the doping levels of both nitrogen (N) and phosphorus (P) in PA-AIBN facilitated the long-wavelength emission RTP. The increased sp2 conjugated carbon core of PA-AIBN narrowed the optical band gap, contributing to the long-wavelength emission. Taken together, these factors cooperatively promoted the long-wavelength emission of RTP. Importantly, the PA-AIBN synthesized in this study exhibited a broad half-peak width and long-wavelength emission. It was successfully used in the preparation of white-light-emitting diodes without the need for commercial phosphor powder, demonstrating its enormous potential for practical lighting devices. [ABSTRACT FROM AUTHOR]

• A new type of phosphorescent material without metal or organic fluorophores. • Carbon-related defects leading the intersystem crossing-based phosphorescence. • The rigid silica network ensuring the longevity of the phosphorescent emission. • Time-gated afterglow imaging system eliminating the tissue-autofluorescence. • Clear visualization-based diagnosis of subcutaneous tumors by high-contrast imaging. Room-temperature phosphorescence (RTP) has tremendous potential in optics and photonics. Unlike fluorescence, RTP has substantial afterglow signals even after the excitation light is removed, which allows for extended acquisition times and higher signal-to-noise ratio under time-gated bioimaging. However, conventional RTP materials, both metal-containing and metal-free organic compounds, typically have limited photostability and inherent toxicity, making them unsuitable for long-term biological applications. Here, we report metal- and organic fluorophore-free silica nanoparticles (SNPs) that facilitate long-lived phosphorescence and exhibit RTP for high-contrast bioimaging. Polycondensation of silicon precursors and silyl biphenyls forms biphenyl-doped SNPs (bSNPs), and thermal decomposition of biphenyl moieties generates optically active defects in the biphenyl-bonded silicate network. The calcined bSNPs (C-bSNPs) have RTP-related biphenyl defects composed of carbon impurities, corresponding to spectroscopic measurements and ab initio calculations. Facile surface functionalization of defect-engineered C-bSNPs with tumor-targeting peptides while maintaining long-lived RTP allows for tissue autofluorescence-free in vivo bioimaging for cancer diagnosis, surpassing the limitations of continuous-wave imaging. [ABSTRACT FROM AUTHOR]

[Display omitted] Due to the high temperature that can easily lead to non-radiative transitions of triplet excitons, obtaining high-temperature phosphorescence (HTP) materials is challenging. Herein, using diarylfuro[3,2- b ]pyridines as the guest molecules and polyacrylic acid (PAA) as the host molecule, the two-component doped materials exhibit green room-temperature phosphorescence (RTP) with afterglow times of 2–8 s, delayed lifetimes of 256–939 ms, and phosphorescence quantum efficiencies of 140.3–21.2 %, and green HTP emissions with 2 s afterglow and 208 ms delayed lifetime at 373 K. The HTP activity of the doped system originates from the rigid environment provided by PAA , planar and rigid molecular structures of diarylfuro[3,2- b ]pyridines, and strong interactions between PAA and diarylfuro[3,2- b ]pyridines. Furthermore, using organic small molecules as the reference host molecules, compared to benzophenone, 5-methylphthalic anhydride, and butane-1,2,3,4-tetracarboxylic acid with chemical structures similar to PAA result in better RTP/HTP properties, revealing that strong interactions between host and guest molecules play a very important role in ultralong phosphorescence emissions of these host–guest doped materials. Moreover, these doped materials based on diarylfuro[3,2- b ]pyridines can be developed as advanced anti-counterfeiting and encryption materials. This result provides valuable reference for developing excellent RTP/HTP materials based on N,O-containing fused-ring compounds. [ABSTRACT FROM AUTHOR]

[Display omitted] • CDs-based materials with multi-mode optical properties have been prepared. • The weak/strong interactions tuning strategies have been studied in depth. • The potential multi-mode optical applications have been demonstrated. Carbon dots (CDs) materials are currently gaining significant attention for applications in bioimaging, fluorescent sensing, anti-counterfeiting, therapeutics, catalysis and other areas. However, efficient and attractive CDs with multi-mode luminescence and tunable spectra through simple modification strategy are still urgently needed for multifunctional optical applications and mechanism exploration. Herein, we demonstrate two rationally designed and completely different CDs surface tuning strategies, which can generate multi-mode optical properties including multi-color fluorescence (FL), room-temperature phosphorescence (RTP) and aggregation-induced emission (AIE). The optical properties after weak interactions modification are characterized by freedom and switchability, while the optical properties after strong interaction modification are characterized by compulsion and non-switchability. Moreover, it is further demonstrated that the cell imaging, light-emitting devices (LEDs), "and" logic gate and anti-counterfeiting applications based on multi-mode optical effects. This study not only provides a new model system for understanding the surface states of CDs, but also opens up opportunities for new applications of multi-mode optical materials for various purposes. [ABSTRACT FROM AUTHOR]

• Colorful afterglow films based on chitosan derivatives are prepared. • Matrix complexes can induce significant RTP enhancement. • Regulating energy level of phosphors by matrix environment. • More rigid environment construction by binary matrix system. • Applications in smart package and multiple antibacterial coating films. Incorporating phosphors into polymer matrix is a relatively mature method to develop organic room-temperature phosphorescent (RTP) materials but still needs to be further explored because of limited investigations about the effect of different matrix on the RTP properties of the same guest molecule. Colorful RTP (from blue to red, with τ afterglow up to 1736 ms) in carboxymethyl chitosan (CC) systems was achieved in this work. To improve the RTP performance, quaternary chitosan (QC) was introduced to build a binary matrix system, which extended the lifetime by 200 ms and increased the phosphorescence quantum yield to 3.51 times. Systematic characterizations and theoretical calculations indicated that the RTP materials obtained from binary matrix had higher ion group density and stronger dipole–dipole interactions, which could narrow the singlet–triplet energy gap and promote the triplet excitons generation. Compared to single matrix, binary matrix could also provide more crosslinked networks to better stabilize triplet excitons, thus synergistically enhancing the RTP. Finally, based on the good biocompatibility and antibacterial properties of chitosan and phosphorescent emission, the films were expected to be used for monitoring the integrity of the package and multiple antibacterial coating films. [ABSTRACT FROM AUTHOR]

A powerful strategy of carbon component engineering is proposed for the synthesis of scandium/cysteine functional materials (Sc/Cys-FMs) with tunable optical bandgap, achieving the transition from room temperature phosphorescence to photothermal properties. [Display omitted] • The bandgap of Sc/Cys-FMs is regulated by cysteine ligands. • The mechanism of tunable bandgap is ascribed to carbon component engineering. • Sc/Cys-FMs can be used for dynamic phosphorescent anti-counterfeiting. Bandgap tunability plays an important role in controlling the photophysical properties of semiconductor material. In this work, we propose a powerful carbon component engineering strategy for regulating the optical bandgap of scandium/cysteine functional materials (Sc/Cys-FMs) that are synthesized by a facile one-pot hydrothermal method. The band structure of Sc/Cys-FMs is closely related to the Cys ligands. As Cys amount rises, the obtained Sc/Cys-FMs exhibit the red-shifted room-temperature phosphorescence (RTP) emission from Sc/Cys-FMs-50 (3.01 eV) to Sc/Cys-FMs-150 (2.14 eV), accompanied by a decrease in quantum efficiency and an increase in lifetime. Meanwhile, the Sc/Cys-FMs show a unique time-dependent phosphorescence color (TDPC) phenomenon, with a dynamic transition of RTP color from yellow to green as the decay time prolongs because of the emission-dependent lifetime. As the amount of Cys further increases, the bandgap can be continuously reduced to 1.88 eV (Sc/Cys-FMs-300) and 1.56 eV (Sc/Cys-FMs-600), causing the quenching of RTP emission and significantly enhanced photothermal properties. The continuously decreasing bandgap has been proven to be directly ascribed to the increase of carbon component in Sc/Cys-FMs. Considering the TDPC properties, Sc/Cys-FMs can be well used for dynamic phosphorescent anti-counterfeiting. This work not only develops a scalable method for preparing functional materials with superior RTP and photothermal properties, but also proposes the carbon component engineering strategy to achieve bandgap tunability of materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Multicolor, ultra-long room-temperature phosphorescent polymer materials produced. • Polymer Doping Systems with Flexible Processability. • 3D phosphorescent materials can still exhibit long afterglow after 30 days underwater. • Patterned security labels with full-color dynamic phosphorescence. Room-temperature-phosphorescent (RTP) metal-free organic polymer materials with long-lasting luminescence properties have received considerable attention in the field of optical materials. Herein, we report unique RTP polymeric materials with ultralong-lasting multicolor luminescence prepared using a series of organic phosphorescent guest molecules and melamine formaldehyde resins. Because of facile thermal cross-linking, these materials exhibit a stable multicolor long-lasting afterglow with a maximum phosphorescence lifetime of > 1 s and a maximum phosphorescence emission efficiency of up to 3.4 %. In addition, polymer doping systems with flexible processability were easily printed on 2D substrates and further used as patterned security labels with full-color dynamic phosphorescence. Further, different materials were combined to form a ternary digital encryption system. In addition, although reports on 3D-printed phosphorescent materials are scarce, by using a similar thermoforming method, we successfully prepared a 3D-molding phosphorescent material that can exhibit a satisfactory long-lasting afterglow even after it is kept underwater for 30 days. In conclusion, this work will usher in advancements in the development and application of metal-free polymer-based RTP materials with long-lasting luminescence and 3D printing potential. [ABSTRACT FROM AUTHOR]

• Novel 3D Ca-MOFs with a visible afterglow lasting about 13 s. • Scaled-up Synthesis of Ca- MOFs with Wide Range of pH Stability. • Long Afterglow Anti-Counterfeiting Measures: Enabling Long Afterglow for Dynamic Anti-Counterfeiting Procedures. • Dynamic Applications and Program Design of Phosphorescent Ca-MOFs in Anti-Counterfeiting. Calcium-based metal–organic frameworks (Ca-MOFs) with room-temperature phosphorescence (RTP) properties are promising for applications. Herein, two 3D Ca-MOFs with robust RTP have been successfully synthesized with scaled-up production. The afterglows of these two Ca-MOFs are visible to the naked eye in darkness that lasts for approximately 13 s once they are excited with 365 nm UV light. It is mainly attributed to the rigid and dense structures of 3D Ca-MOFs via 4,5-Imidazole dicarboxylic acid tugging Ca2+ elucidated by means of single-crystal X-ray diffraction and density functional theory (DFT). Furthermore, a program was designed for dynamic anti-counterfeiting based on the long afterglow properties of Ca-MOFs, which can be extended for all kinds of material with long afterglow. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cellulose-based RTP material with wide-range phosphorescence emission is prepared. • Color-tunable emission, including white-light, is achieved via complementary color strategy. • This material shows potential application as colored water-based inks for information encryption. Developing color-tunable pure organic room-temperature phosphorescent (RTP) materials based on biopolymers is of great significance for efficient utilization of natural resources, yet still challenging. Herein, tunable multicolor phosphorescence emission, including white-light, is achieved in cellulose-based RTP materials by co-organizing complementary cyan and red organic phosphors into the strong hydrogen-bonding networks of cellulose. The non-radiative transition of phosphors can be effectively suppressed by the high density of hydrogen bonding among the cellulose chains as well as the covalent interaction. The difference in optical properties between the two phosphors enables the adjustment of the phosphorescence emission color of the material from green to cyan, white and then red. It is demonstrated that the designed material can be used as versatile inks for pattern drawing and information encryption, with favorable multicolor emission and excellent aqueous processability. Therefore, considering the biodegradability and sustainability of cellulose materials, cellulose-based RTP has enormous potential in advanced anti-counterfeiting and information encryption as eco-friendly phosphorescent inks and coatings. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two sets of isomeric TADF emitters are designed and synthesized. • The RTP efficiency and lifetime are regulated by tuning their energy levels and molecular packing modes through isomer and substituent engineering. • 4-CzAIAd displays the longest RTP lifetime of 301 ms. Metal-free organic phosphorescent materials are crucial for the advancement of optoelectronics and bioelectronics. Nonetheless, achieving rational control over the performance of room-temperature phosphorescence (RTP) presents a significant challenge. In this study, two sets of isomeric thermally activated delayed fluorescence (TADF) emitters with a donor–acceptor (D-A) configuration are designed and synthesized. Their RTP efficiency and lifetime are regulated by tuning their energy levels and molecular packing modes through isomer and substituent engineering. All of these materials exhibited afterglow emission, with the exception of 4-CzAIPh. A comprehensive investigation was conducted on the packing modes in the crystalline state, which revealed that the three RTP materials possess strong π-π interactions and numerous intermolecular forces, providing stability to the long-lived triplet excitons of RTP. Especially, 4-CzAIAd demonstrated the fastest intersystem crossing rate, the smallest fractional free volume and relatively larger spin–orbit coupling between its singlet and triplet states, as well as between its triplet state and ground state, which explains its longest phosphorescence lifetime of 301 ms. [ABSTRACT FROM AUTHOR]

[Display omitted] Schematic illustration for the preparations of C-SiNDs@UA, Y-SiNDs@UA, O-SiNDs@UA, and R-SiNDs@UA. And a possible mechanism of the photophysical processes of C-SiNDs@UA, Y-SiNDs@UA and R-SiNDs@UA nanocomposites. • The silicon-nanodot-based nanocomposite materials realized multi-color afterglows (cyan, yellow, orange, and red). • Silane was used owing to triplet-exciton stabilization afforded by covalent Si-C and Si-O bonds. • The microenvironment consisting of the highly rigid network structures played a critical role in reducing the non-radiative relaxation. • The information security systems were established using single-, multiple-, and red-afterglow-based 5D information encryption methods. Multi-color phosphorescent materials have received considerable attention owing to their wide range of applications. However, a standardized strategy for producing tunable phosphorescent colors has rarely been developed. Herein, we report the preparation of ingeniously designed silicon-nanodot-based nanocomposite materials with multi-color afterglows (cyan, yellow, orange and red) using a simple hydrothermal method that involves combining silane, dyes and urea. Notably, the silane formed silicon nanodots in situ by participating in the hot-melt recrystallization process of urea, accompanied by the formation of new covalent and hydrogen bonds. These nanodots become immobilized in the rigid network structure formed during urea recrystallization to deliver highly efficient phosphorescence. More impressively, orange and red afterglow materials were successfully synthesized based on the phosphorescence Förster resonance energy transfer principle. These properties led to the establishment of the information security systems using single-, multiple-, and 5D information encryption methods. Given the universality of this method, this standardized strategy not only highlights the potential of constructing multifunctional phosphorescent materials from silane, but also provides a novel design principle for the synthesis of full-color afterglow materials. [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]

• Multi-color phosphorescent CDs were prepared. • These phosphorescent CDs accelerated the production of 1O 2. • Graphitization degrees and amounts of C O on RTP were first elucidated. • The proposed multi-color CDs showed the application of LED lamps. Room-temperature phosphorescence with multiple-color activated the widespread interest owing to their promising applications, howbeit, there still exist the insurmountable challenge, especially for elucidating their photoluminescence mechanism and tunable emissions. Here we systematically proposed several carbon dots (CDs) with different degrees of graphitization and amounts of carbonyl while sulfuric acid and ethanol played the critical roles. In brief, sulfuric acid functioned as the carbonization and strong oxidization reagent, while the increasing volumes of ethanol gradually reduced the boiling point of the reactions. Significantly, the energy of these phosphorescent CDs transferred from their excited triplets to oxygen molecules once they were irradiated by UV in aqueous, resulting in the production of the singlet oxygen to oxidize 3,3′,5,5′-tetramethylbenzidine. This finding indirectly provided the evidence for the existence of the phosphorescence rather than delayed fluorescence. Towards the photoluminescence mechanism, their fluorescence of CDs was originated from π-π* transition of C C in the carbon cores and n-π* transition of C O on the surfaces, while RTP was mainly attributed to n-π* transition of the carbonyls. The further evidence suggested that the CDs with different graphitization degrees and amounts of C O regulated their multiple-color phosphorescence. Besides, we employed these CDs for information encryption and preparing LED lamps. [ABSTRACT FROM AUTHOR]

• Ultralong polyacrylamide-based RTP materials have been facilely prepared. • Reversible RTP responsiveness to water and heat stimuli has been achieved. • Color-tunable phosphorescence emission with varied excitation wavelength has been realized. • These new RTP materials show potential application in anti-counterfeiting and information encryption. Pure organic room-temperature phosphorescent (RTP) materials have evoked increasing attention due to their potential application in many fields. However, the preparation of ultralong and color-tunable RTP materials were still facing challenges. Herein, two facile strategies were applied to construct ultralong RTP materials based on non-covalent and covalent linking of sulfanilic acid (SA) on amorphous polyacrylamide (PAM) framework. The hydrogen bonding in PAM/SA and poly(acrylamide- co -4-acrylamidobenzenesulfonic acid) (PAMABS) can effectively help to suppress non-radiative transition, and induce ultralong RTP emission at ambient condition. The RTP emission intensity and lifetime of PAM/SA can be controlled by the molar ratio of acrylamide to SA. Remarkably, PAMABS shows excitation-dependent color-tunable phosphorescence emission. Due to the destructive effect of water on the system rigidity, PAM/SA and PAMABS both exhibit RTP responsiveness to water and heat stimuli. Furthermore, the convenient preparation and excellent properties enable these new organic RTP materials extremely suitable for anti-counterfeiting and information encryption. [ABSTRACT FROM AUTHOR]

[Display omitted] • A one chromophore with multi-excited states strategy is proposed for the de novo design of single white-emitting polymers. • P(DMPAc-O-DBTDO) is developed based on a characteristic D-O-A geometry. • P(DMPAc-O-DBTDO) shows not only fluorescence and TADF from S 1 , but also RTP from T 1. • Solution-processed WOLEDs are realized with tunable CIE coordinates and CCT for different illumination requirements. Single white-emitting polymers (SWPs) based on multi-chromophores with different colors are believed to show a great potential in solution-processed white light-emitting diodes (WOLEDs). However, they suffer from the extremely low loadings (one ten thousandth to one thousandth) for long-wavelength chromophores when incorporated into SWPs. To solve this bottleneck, we newly propose a one chromophore with multi-excited states strategy for the de novo design of SWPs. By adopting acridine as the donor (D), dibenzothiophene-S,S-dioxide as the acceptor (A) and oxygen as the linker between D and A to constitute the central chromophore fragment, P(DMPAc-O-DBTDO) is successfully developed to possess not only fluorescence and thermally-activated delayed fluorescence from the lowest singlet state (S 1), but also room-temperature phosphorescence from the lowest triplet state (T 1). As a consequence, a very broad electroluminescence that covers the whole visible region from 400 to 750 nm is realized, leading to an efficient and stable white light with a peak power efficiency of 7.5 lm W−1 (9.5 cd A-1, 3.7%). Meanwhile, the Commission Internationale de l'Eclairage (CIE) coordinates and correlated color temperature (CCT) could be well tuned in a wide doping concentration window (15–100%) for different illumination requirements. [ABSTRACT FROM AUTHOR]

[Display omitted] • Polymers with multicolor luminescence by doping with a single dye. • Polymer-matrixed naphthalene diimide single-luminogen. • Reversible, dynamic wide-range emission color. • A new mechanism for photo-enhanced RTP luminescence was presented. Smart materials with dynamic luminescence-color are potentially useful for sensors, displays and data storage devices. Herein a new photoresponsive luminescent material with a dynamic wide-range emission color was successfully developed through individually dispersing naphthalene diimide (NDI) possessing aliphatic carboxylic acid substitution on the diimide nitrogen atoms (NDI-COOH) into polymer matrix. Experiments and mechanism studies demonstrated that it was the photo-generated stable NDI radical anions that led to the unique photoresponsive dynamic emission color. Notably, a new mechanism involving twice energy transfer between NDI and NDI radical anions for photo-enhanced room-temperature phosphorescence (RTP) luminescence was presented. The present dynamic reversible emission approach, not only outlines a principle for the design of photo-induced radical anions with tunable luminescence, but also expands the scope of encryption and decryption of confidential information. [ABSTRACT FROM AUTHOR]

[Display omitted] • Syntheses and crystal structures of the five isomeric ICZs are completely revealed. • Organic amorphous afterglows of the indolocarbazole families are firstly presented. • ICZ- P 2 realized PLQY, afterglow lasting time and lifetime of 31.06%, 35 s and 2.32 s. • Data security applications based on the afterglows of the ICZ-PVA inks are developed. Indolocarbazoles (ICZs) and their derivates were immensely studied in the fields of organic opto-electronics, sensors and anti-cancer agents. However, the afterglow researches, the comprehensive syntheses and crystal structures of the isomeric ICZs remained shortages. Currently, the organic afterglows were mainly focused on the crystalline states, showing restrictions and inconveniences in practical applications, the organic amorphous afterglows were more favorable but were limitedly documented. Herein, the syntheses, single crystal structures, afterglow studies and data protection applications of the ICZ families with five isomers were together presented for the first time. For these ICZ crystals, the planar configurations and high void rates made them prone to stack and vulnerable to the O 2 and humidity, affected by these factors, they were hard to radiate phosphorescence at room temperature, which can be more easily aroused at 77 K. By doping the ICZ into PVA, a rigid and confined environment was built by the hydrogen bond interaction between the –NH and –OH unit in the ICZ and PVA chain, greatly hindering the molecular motion, O 2 and humidity quenchers. Consequently, the triplet states were efficiently stabilized, the nonradiative transitions were highly suppressed, blooming the phosphorescence of these ICZs at room temperature, the brilliant afterglow can be straight witnessed by the naked eyes. Impressively, the highest photoluminescence efficiency of 31.06% was obtained by the ICZ– o , the longest afterglow lasting time and phosphorescent lifetime of 35 s and 2.32 s were achieved by the ICZ– p 2, rivaling to the reported organic amorphous afterglows. It's believed that the synthetic, crystal structural and afterglow studies of the ICZ families should find a promising avenue for developing new organic amorphous afterglow materials and their applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Circularly polarized room temperature phosphorescence obtained in copolymers. • Phosphorescence switch induced by acid-based regulated external heavy atom effect. • Double encryption application based on phosphorescence lifetime discrimination. The development of circularly polarized luminescence (CPL) materials has attracted much attention because of their potential application in chiral recognition and optical device. However, current achievements mainly focus on circularly polarized fluorescence, and circularly polarized room temperature phosphorescence (CPRTP) materials remain a great challenge especially the pure organic amorphous CPRTP materials. Herein, a CPL and CPRTP pure organic amorphous polymer R/S-BPNaP are developed by radical binary copolymerization of acrylamide and chiral binaphthyl derivates. More interestingly, the copolymers show tunable acid-base responsive switching RTP emission properties and can be applied in the area of encryption. [ABSTRACT FROM AUTHOR]

The resolution of graphical abstract has been improved. [Display omitted] • A smart strategy was developed to prepare metal-free BN-based RTP materials. • The metal-free BN-based RTP materials exhibit ultra-long lifetime. • The strong interaction between BNDs and B 2 O 3 Matrix prohibits non-radiative transition. Developing metal-free room-temperature phosphorescence (RTP) materials with ultralong lifetimes in dry and wet states simultaneously has been widely concerned due to their potential applications, which is also a tough challenge up to now. Herein, a smart construction strategy is proposed to in-situ embed boron nitride dots (BNDs) into an isogenous B 2 O 3 matrix. The BND-based materials exhibit unexpected bluish-green RTP in solid and various wet conditions (water, oxidants, organic solvents, strong acids and bases). The RTP lifetime of them in powder is as long as ~ 1.7 s, lasting over 10 s to naked eye. B 2 O 3 matrix can not only uniformly disperse the BNDs in it, but also provide a rigid environment via forming hydrogen-bonded and covalently bonded interactions between them to strongly stabilize the triplet states excitions on the dots from nonradiative deactivation. More interestingly, RTP quenching of the BND-based powder in various solutions is effectively suppressed because the B 2 O 3 matrix is not collapsed in them. For instance, the RTP lifetime in water is as long as ~ 0.9 s. Based on the distinctive RTP properties in dry and various harsh wet states, the applications of the BND-based RTP materials in multi-level anti-counterfeiting and information encryption are demonstrated. [ABSTRACT FROM AUTHOR]

• Amorphous pure organic copolymers with multicolor RTP have been prepared. • Tunable multicolor RTP, including white-light emission, has been achieved. • Time-dependent multicolor afterglow, including white afterglow, has been realized. Research on amorphous pure organic room-temperature phosphorescent (RTP) materials has been receiving great attentions in recent years, while smart materials with color-tunable RTP emission are still rare, especially those with white-light emission and white afterglow. A series of pure organic amorphous copolymers with dual-emissive RTP have been synthesized by copolymerizing benzoic acid, 4-bromo-1,8-naphthalic anhydride and acrylamide with different feeding ratios. The two phosphor moieties display different absorption spectra, different RTP emission spectra and lifetimes, which can induce tunable multicolor RTP with different feeding ratios and different excitation wavelengths, including white-light emission (CIE coordinates (0.32, 0.33)). Moreover, time-dependent multicolor afterglow can also be observed because of the different decay lifetimes of these two phosphors, including nearly white afterglow. Since the acrylamide polymers are water-soluble, their RTP emission can be quenched with the existence of water by breaking the rigid structure, which makes their emission color tunable under different humidity conditions. [ABSTRACT FROM AUTHOR]