One-dimensional hybrid copper halides with high-efficiency photoluminescence as scintillator.

A new one-dimensional hybrid [APCHA]Cu2I4 was designed and applied as an X-ray scintillator. It exhibits broad-band green emission with a high PLQY of 74.80% and excellent stability. It demonstrates radioluminescence property with a light yield of 28 336 photons MeV-1, detection limit of 41 nGyair s-1, and high spatial limit of 13.95 lp mm-1 in X-ray imaging.

One-Dimensional Red Light-Emissive Organic Manganese(II) Halides as X-Ray Scintillators.

Although metal halide-based X-ray scintillators have obtained significant development with adjustable radioluminescent spectral range, the red light-emitting scintillator has been sparsely reported and remains a great challenge until now. To remedy this research blank, we investigated the scintillating property of red light-emissive one-dimensional (1D) organic manganese halide of (MBIZ)(MnCl3H2O)·H2O (MBIZ = 2-methyl-1H-benzoimidazolium) with a high PLQY of 71% under UV light excitation. Remarkably, this manganese halide single crystal exhibits a compelling X-ray scintillating property in the red light spectral range with a light yield of 19 600 photons MeV-1 and detection limit of 0.204 µGy/s, which is significantly better than the standard dosage for X-ray diagnostics. Furthermore, this manganese halide also exhibits excellent radiation resistance ability toward long-term continuous irradiation of high-dose X-ray with stable radiophotoluminescence intensity. Benefiting from the abovementioned combined merits, (MBIZ)(MnCl3H2O)·H2O demonstrates high-performance X-ray imaging with an outstanding spatial resolution of 11.1 lpmm-1. As far as we know, this is an infrequent red-emissive X-ray scintillator in metal halide materials, which highlights a successful structural design concept to explore new manganese halides as more desirable scintillators and expand the application field in medical diagnosis.

Hybrid metal halide family with color-time-dual-resolved phosphorescence for multiplexed information security applications.

Luminescent materials with engineered optical properties play an important role in anti-counterfeiting and information security technology. However, conventional luminescent coding is limited by fluorescence color or intensity, and high-level multi-dimensional luminescent encryption technology remains a critically challenging goal in different scenarios. To improve the encoding capacity, we present an optical multiplexing concept by synchronously manipulating the emission color and decay lifetimes of room-temperature phosphorescence materials at molecular level. Herein, we devise a family of zero-dimensional (0D) hybrid metal halides by combining organic phosphonium cations and metal halide tetrahedral anions as independent luminescent centers, which display blue phosphorescence and green persistent afterglow with the highest quantum yields of 39.9 % and 57.3 %, respectively. Significantly, the luminescence lifetime can be fine-tuned in the range of 0.0968-0.5046 µs and 33.46-125.61 ms as temporary time coding through precisely controlling the heavy atomic effect and inter-molecular interactions. As a consequence, synchronous blue phosphorescence and green afterglow are integrated into one 0D halide platform with adjustable emission lifetime acting as color- and time-resolved dual RTP materials, which realize the multiple applications in high-level anti-counterfeiting and information storage. The color-lifetime-dual-resolved encoding ability greatly broadens the scope of luminescent halide materials for optical multiplexing applications.

Synchronously Improved Multiple Afterglow and Phosphorescence Efficiencies in 0D Hybrid Zinc Halides with Ultrahigh Anti-Water Stabilities.

Zero-dimensional (0D) hybrid metal halides have been emerged as room-temperature phosphorescence (RTP) materials, but synchronous optimization of multiple phosphorescence performance in one structural platform remains less resolved, and stable RTP activity in aqueous medium is also unrealized due to serious instability toward water and oxygen. Herein, we demonstrated a photophysical tuning strategy in a new 0D hybrid zinc halide family of (BTPP)2ZnX4 (BTPP = benzyltriphenylphosphonium, X = Cl and Br). Infrequently, the delicate combination of organic and inorganic species enables this family to display multiple ultralong green afterglow and efficient self-trapped exciton (STE) associated cyan phosphorescence. Compared with inert luminescence of [BTPP]+ cation, incorporation of anionic [ZnX4]2- effectively enhance the spin-orbit coupling effect, which significantly boosts the photoluminescence quantum yield (PLQY) up to 30.66% and 54.62% for afterglow and phosphorescence, respectively. Synchronously, the corresponding luminescence lifetime extend to 143.94 ms and 0.308 µs surpassing the indiscernible phosphorescence of [BTPP]X salt. More importantly, this halide family presents robust RTP emission with nearly unattenuated PLQY in water and harsh condition (acid and basic aqueous solution) over half a year. The highly efficient integrated afterglow and STE phosphorescence as well as ultrahigh aqueous state RTP realize multiple anti-counterfeiting applications in wide chemical environments.

Ultrafast Visual Detection of a Trace Amount of Water by Highly Efficient Hybrid Manganese Halides.

A quantitative water detection method is urgently needed in storage facilities, space exploration, and the chemical industry. Although numerous physical techniques have been widely utilized to determine the water content, they still suffer from many disadvantages such as highly expensive special instruments, complicated analysis processes, etc. Hence, a convenient, rapid, and sensitive water analysis method is highly desirable. Herein, we developed a visual fluorescence sensing technology for water detection based on reversible PL off-on switching of organic-inorganic hybrid zero-dimensional (0D) manganese halides. In this work, a family of hybrid manganese halides were synthesized through a facile solution method, namely, [NH4(18-Crown-6)]2MnBr4, [Ca(18-Crown-6)·3H2O](18-Crown-6)MnBr4, [NH4(dibenzo-18-Crown-6)]2MnBr4, and [Ca(dibenzo-18-Crown-6)·2H2O]MnBr4. Excited by UV light, these highly crystalline manganese halides exhibit strong green light emissions from the d-d electron transition of Mn2+ with near-unity photoluminescence quantum yield and submillisecond lifetime. Benefiting from the dynamic and weak ionic bonding interactions, these 0D manganese halides display reversible water-response on/off luminescence switching but fail in any other aprotic solvents. Therefore, these 0D hybrid manganese halides can be explored as ultrafast visual fluorescence probes to detect the trace amount of water in organic solvents with multiple superiorities of rapid response time (< 2 s), ultralow detection limit (9.71 ppm), excellent repeatability, etc. The reversible water-response luminescent on/off switching also provides a binary optical gate with advanced applications in anticounterfeiting and information security, etc.

Crystal-Rigidifying Strategy in Hybrid Manganese Halide to Achieve Narrow Green Emission and High Structural Stability.

Although organic-inorganic hybrid Mn2+ halides have advanced significantly, achieving high stability and narrow-band emission remains enormously challenging owing to the weak ionic nature and soft crystal lattice of the halide structure. To address these issues, we proposed a cationic engineering strategy of long-range cation π···π stacking and C-H···π interactions to simultaneously improve the crystal structural stability and rigidity. Herein, two organic zero-dimensional (0D) manganese halide hybrids of (BACQ)2MnX4 [BACQ = 4-(butylamino)-7-chloroquinolin-1-ium; X = Cl and Br] were synthesized. (BACQ)2MnX4 display strong green-light emissions with the narrowest full width at half-maximum (fwhm) of 39 nm, which is significantly smaller than those of commercial green phosphor ß-SiAlON:Eu2+ and most of reported manganese halides. Detailed Hirshfeld surface analyses demonstrate the rigid environment around the [MnX4]2- units originating from the interactions between [BACQ]+. The rigid crystal structure weakens the electron-phonon coupling and renders narrow fwhm of these manganese halides, which is further confirmed by temperature-dependent emission spectra. Remarkably, (BACQ)2MnX4 realizes outstanding structural and luminescence stabilities in various extreme environments. Benefiting from the excellent performance, these Mn2+ halides are used to assemble light-emitting diodes with a wide color gamut of 105% of the National Television System Committee 1931 standard, showcasing the advanced applications in liquid-crystal-display backlighting.

Zero-Dimensional Copper(I) Halide Microcrystals as Highly Efficient Scintillators for Flexible X-ray Imaging.

Commercially available rare-earth-doped inorganic oxide materials have been widely applied as X-ray scintillators, but the fragile characteristics, high detection limit, and harsh preparation condition seriously restrict their wide applications. Furthermore, it remains a huge challenge to realize X-ray flexible imaging technology for real-time monitoring of the curving interface of complex devices. To address these issues, we herein report two isostructural cuprous halides of zero-dimensional (0D) [AEPipz]CuX3·X·H2O (AEPipz = N-aminoethylpiperazine, X = Br and I) with controllable size to nanosize crystal as highly efficient scintillators toward flexible X-ray imaging. These cuprous halides exhibit highly efficient cyan photoluminescence and radioluminescence emissions with the highest quantum yield of 92.1% and light yield of 62,400 photons MeV-1, respectively, surpassing most of the commercially available inorganic scintillators. Meanwhile, the ultralow detection limit of 95.7 nGyair s-1 was far below the X-ray dose required for diagnosis (5.5 µGyair s-1). More significantly, the flexible film is facilely assembled with excellent foldability and high crack resistance, which further acts as a scintillation screen achieving a high spatial resolution of 17.4 lp mm-1 in X-ray imaging, demonstrating the potential application in wearable radiation radiography. The combined advantages of high light yield, low detection limit, and excellent flexibility promote these 0D cuprous halides as the most promising X-ray scintillators.

Zero-dimensional hybrid tin halides with stable broadband light emissions.

Considering the instability and toxicity of 3D Pb-based perovskite nanocrystals, lead-free low-dimensional organic-inorganic hybrid metal halides have attracted widespread attention as potential substitutes. Herein, two new tin-based 0D halides [H4BAPP]SnBr5·Br and [H4BAPP]SnCl5·Cl·H2O (BAPP = 1,4-bis(3-aminopropyl)piperazine) were synthesized successfully based on [SnX5]3- as an emission center. Typically, [H4BAPP]SnBr5·Br and [H4BAPP]SnCl5·Cl·H2O display broadband yellow and yellow-green light emissions originating from the radiative recombination of self-trapped excitons (STEs). The photoluminescence quantum yields (PLQYs) of the two compounds were calculated to be 19.27% and 2.36%, respectively. Furthermore, the excellent chemical and thermal stability and broadband light emissions reveal their potential application in solid-state white lighting diodes.

Exploring 0D lead-free metal halide with highly efficient blue light emission and high-sensitivity photodetection.

Environmentally friendly and highly efficient blue luminescent materials are an unremitting pursuit in the optoelectronic field. Herein, we assembled a new 0D lead-free metal halide of (F-PPA)ZnBr4, which exhibits narrow blue light emission with a remarkable PLQY of 50.15%, high stability and high detection sensitivity toward UV light. These results indicate the potential for the application of low-dimensional zinc-based halides in multiple optoelectronic devices.

Near-Unity Green Luminescent Hybrid Manganese Halides as X-ray Scintillators.

The increasing demands in optoelectronic applications have driven the advancement of organic-inorganic hybrid metal halides (OIMHs), owing to their exceptional optical and scintillation properties. Among them, zero-dimensional (0D) low-toxic manganese-based scintillators have garnered significant interest due to their exceptional optical transparency and elevated photoluminescence quantum yields (PLQYs), making them promising for colorful light-emitting diodes and X-ray imaging applications. In this study, two OIMH single crystals of (Br-PrTPP)2MnBr4 (Br-PrTPP = (3-bromopropyl) triphenylphosphonium) and (Br-BuTPP)2MnBr4 (Br-BuTPP = (4-bromobutyl) triphenylphosphonium) were prepared via a facile saturated crystallization method. Benefiting from the tetrahedrally coordinated [MnBr4]2- polyhedron, both of them exhibited strong green emissions peaked at 517 nm owing to the d-d electron transition of Mn2+ with near-unity PLQYs of 99.33 and 86.85%, respectively. Moreover, benefiting from the high optical transparencies and remarkable luminescence properties, these manganese halides also exhibit excellent radioluminescent performance with the highest light yield of up to 68,000 photons MeV-1, negligible afterglow (0.4 ms), and linear response to X-ray dose rate with the lowest detection limit of 45 nGyair s-1. In X-ray imaging, the flexible film made by the composite of (Br-PrTPP)2MnBr4 and PDMS shows an ultrahigh spatial resolution of 12.78 lp mm-1, which provides a potential visualization tool for X-ray radiography.

A 0D hybrid lead-free halide with near-unity photoluminescence quantum yield toward multifunctional optoelectronic applications.

Zero-dimensional (0D) hybrid metal halides have emerged as highly efficient luminescent materials, but integrated multifunction in a structural platform remains a significant challenge. Herein, a new hybrid 0D indium halide of (Im-BDMPA)InCl6·H2O was designed as a highly efficient luminescent emitter and X-ray scintillator toward multiple optoelectronic applications. Specifically, it displays strong broadband yellow light emission with near-unity photoluminescence quantum yield (PLQY) through Sb3+ doping, acting as a down-conversion phosphor to fabricate high-performance white light emitting diodes (WLEDs). Benefiting from the high PLQY and negligible self-absorption characteristics, this halide exhibits extraordinary X-ray scintillation performance with a high light yield of 55 320 photons per MeV, which represents a new scintillator in 0D hybrid indium halides. Further combined merits of a low detection limit (0.0853 µGyair s-1), ultra-high spatial resolution of 17.25 lp per mm and negligible afterglow time (0.48 ms) demonstrate its excellent application prospects in X-ray imaging. In addition, this 0D halide also exhibits reversible luminescence off-on switching toward tribromomethane (TBM) but fails in any other organic solvents with an ultra-low detection limit of 0.1 ppm, acting as a perfect real-time fluorescent probe to detect TBM with ultrahigh sensitivity, selectivity and repeatability. Therefore, this work highlights the multiple optoelectronic applications of 0D hybrid lead-free halides in white LEDs, X-ray scintillation, fluorescence sensors, etc.

High Emission Efficiency and Thermal Stability in Zero-Dimensional Hybrid Zinc Halide as a Blue Light Emitter.

Exploring highly efficient blue-emissive lead-free halide materials is a significant and challenging objective in the study of luminescent materials. This study reports the synthesis of a new zero-dimensional (0D) hybrid zinc halide of [CYP]ZnBr4 (CYP = 1-cyclohexylpiperazine) containing an isolated [ZnBr4]2- tetrahedron. [CYP]ZnBr4 exhibits strong blue light emission with a high photoluminescence quantum yield (PLQY) of 79.22%, surpassing all previously reported 0D zinc halide counterparts. According to the theoretical and experimental studies, the blue light emission is attributed to intrinsic self-trapped excitons resulting from strong electron-phonon coupling and structural deformation. Importantly, [CYP]ZnBr4 demonstrates excellent structural and luminescence stability toward high temperatures (180 °C) over at least half a month. High luminescence efficiency and stability enable [CYP]ZnBr4 to be an efficient blue phosphor to fabricate white light-emitting diodes (LEDs), which produces high-quality white light with a color rendering index (CRI) of 93.1 and a correlated color temperature (CCT) of 5304 K, closely resembling natural sunlight. This white LED also exhibits consistent performance and stability across different drive currents, suggesting the potential for high-power optoelectronic applications. Overall, this study paves the way for the utilization of 0D hybrid halides in advanced solid-state lighting applications.

0D hybrid indium halide as a highly efficient X-ray scintillation and ultra-sensitive fluorescent probe.

Halide perovskite nanocrystal (PNC) of 3D CsPbX3 as a scintillator has aroused intensive attention with advanced applications in radiation detection and X-ray imaging. However, the low light yield and serious toxicity of Pb2+ severely hinder advanced optoelectronic applications. To reduce these fatal shortcomings, a family of new environmentally friendly 0D hybrid lead-free indium halides of [DADPA]InX6·H2O (DADPA = 3,3'-diaminodipropylamine; X = Cl and Br) was prepared. Upon UV excitation, these halides display strong broadband yellow-orange light emissions, and the photoluminescence quantum yield (PLQY) can be optimized up to near unity through the Sb3+-doping strategy. Significantly, high PLQY, negligible self-absorption and low attenuation ability toward X-ray render extraordinary scintillation performance with a high light yield of 51 875 photons MeV-1 and ultralow detection limit of 98.3 nGyair s-1, which is far superior to typical 3D PNC scintillators. Additionally, the ultra-high spatial resolution of 25.15 lp mm-1, negligible afterglow time (2.75 ms) and robust radiant stability demonstrates excellent X-ray imaging performance. To the best of our knowledge, this is the first report on X-ray scintillation based on 0D indium halide materials.

Reversible structural transformations and color-tunable emissions in organic manganese halides.

Herein, we for the first time report a reversible conversion between green-emissive [DMPZ]MnCl4 and red-emissive [DMPZ]4(MnCl6)(MnCl4)2·(H2O)2 (DMPZ = 1,4-dimethylpiperazine) using kinetic and thermodynamic controlling strategies. Significantly, the synchronous structural and emission transformations in single-component organic manganese halides with adjustable emission colors are highlighted.

0D triiodide hybrid halide perovskite for X-ray detection.

In the relentless pursuit of developing high-performance, stable and environmentally friendly materials for X-ray detection, we present a new class of Bi-based hybrid organic-inorganic perovskites. An X-ray detector based on a new zero-dimensional (0D) triiodide-induced lead-free hybrid perovskite, (DPA)2BiI9 (DPA = C5H16N22+), has been developed demonstrating outstanding detection performance, including high X-ray sensitivity (20 570 µC Gyair-1 cm-2), low detectable dose rate (0.98 nGyair s-1), fast response time (154/162 ns) and excellent long-term stability.

Enhanced stability and tunable photoluminescence in Mn2+-doped one-dimensional hybrid lead halide perovskites for high-performance white light emitting diodes.

Organic-inorganic hybrid low-dimensional lead halides have garnered significant interest in the realm of solid-state optical materials due to their unique properties and potential applications. In this study, we report the synthesis, characterization and application of Mn2+-doped one-dimensional (1D) [AEP]PbCl5·H2O hybrid lead halide perovskites with tunable photoluminescence properties. The Mn2+ doping leads to a redshift of the dominant emission wavelength from 463 nm to 630 nm, with the optimal doping concentration resulting in an enhanced photoluminescence quantum yield (PLQY) from less than 1% to 8.96%. The structural and optical stability of these doped perovskites have been thoroughly investigated revealing excellent performance under humid and high-temperature conditions. Perovskite-PVP composite films exhibit high crystallization and bright orange-red emission under UV excitation. Furthermore, we demonstrate the successful fabrication of a white LED device using the Mn2+-doped perovskite in combination with commercial green and blue phosphors. The fabricated LED exhibits a high color rendering index (CRI) of 87.2 and stable electroluminescence performance under various operating currents and extended operation times. Our findings highlight the potential of Mn2+-doped 1D hybrid lead halide perovskites as efficient and stable phosphors for high-performance white light emitting diodes and other optoelectronic applications.

Zero-Dimensional Hybrid Cuprous Halide of [BAPMA]Cu2Br5 as a Highly Efficient Light Emitter and an X-Ray Scintillator.

Lead halide perovskites have been explored as a new kind of promising X-ray with wide applications in radiation-associated fields, but low light yield and serious toxicity extremely restrict further applications. To address these issues, we herein demonstrated one new zero-dimensional (0D) organic-inorganic hybrid cuprous halide of [BAPMA]Cu2Br5 (BAPMA = N,N-Bis(3-aminopropyl) methylamine) containing discrete [Cu4Br10]6- tetramers as excellent lead-free scintillators. Upon UV light excitation, [BAPMA]Cu2Br5 displays highly efficient broadband yellowish-green light emission with one dominant peak at 526 nm, a large Stokes shift of 244 nm, and a high photoluminescent quantum yield of 53.40%. Significantly, this broadband light emission can also be excited by higher-energy X-ray as radioluminescence with a high scintillation light yield of 43,744 photons/MeV. The detection limit of 0.074 µGyair/s is also far less than the required value for regular medical diagnostics of 5.5 µGyair/s. The solution-assembled hybrid structure facilely enables the [BAPMA]Cu2Br5-based scintillation screen to display high-performance X-ray imaging with a spatial resolution of 15.79 lp/mm showcasing potential application in X-ray radiography. In brief, combined merits of low toxicity and cost, negligible self-absorption, a low detection limit, considerable light yield, and spatial resolution highlight the excellent scintillation performance of 0D hybrid cuprous halide.

Stepwise Crystalline Structural Transformation in 0D Hybrid Antimony Halides with Triplet Turn-on and Color-Adjustable Luminescence Switching.

Intelligent stimuli-responsive fluorescence materials are extremely pivotal for fabricating luminescent turn-on switching in solid-state photonic integration technology, but it remains a challenging objective for typical 3-dimensional (3D) perovskite nanocrystals. Herein, by fine-tuning the accumulation modes of metal halide components to dynamically control the carrier characteristics, a novel triple-mode photoluminescence (PL) switching was realized in 0D metal halide through stepwise single-crystal to single-crystal (SC-SC) transformation. Specifically, a family of 0D hybrid antimony halides was designed to exhibit three distinct types of PL performance including nonluminescent [Ph3EtP]2Sb2Cl8 (1), yellow-emissive [Ph3EtP]2SbCl5·EtOH (2), and red-emissive [Ph3EtP]2SbCl5 (3). Upon stimulus of ethanol, 1 was successfully converted to 2 through SC-SC transformation with enhanced PL quantum yield from ~0% to 91.50% acting as "turn-on" luminescent switching. Meanwhile, reversible SC-SC and luminescence transformation between 2 and 3 can be also achieved in the ethanol impregnation-heating process as luminescence vapochromism switching. As a consequence, a new triple-model turn-on and color-adjustable luminescent switching of off-onI-onII was realized in 0D hybrid halides. Simultaneously, wide advanced applications were also achieved in anti-counterfeiting, information security, and optical logic gates. This novel photon engineering strategy is expected to deepen the understanding of dynamic PL switching mechanism and guide development of new smart luminescence materials in cutting-edge optical switchable device.

Multiple Light Source-Excited Organic Manganese Halides for Water-Jet Rewritable Luminescent Paper and Anti-Counterfeiting.

Rewritable luminescent paper is particularly crucial, considering the ultrahigh paper consumption and confidential information security, but a highly desirable stimuli-responsive smart luminescent material with excellent water solubility has rarely been studied. Herein, a new type of rewritable paper made by highly efficient green light emissive zero-dimensional (0D) organic manganese halides is rationally designed by virtue of the reversible photoluminescence (PL) off-on switching. Specifically, the green emission can be linearly quenched by water vapor in a wide humidity range and again recovered in a dry atmosphere, which make it a smart hydrochromic PL off-on switching and humidity sensor. Benefiting from the reversible luminescence off-on switch and excellent water solubility, rewritable luminescent paper is realized through water-jet security printing technology on 0D halide-coated commercial paper with high resolution. The printed/written information can be easily cleaned by slight heating with outstanding "write-erase-write" cycle capabilities. In addition, multiple light source-induced coincident green light emissions further provide convenience to realize anti-counterfeiting, encryption and decryption of confidential information, and so forth. This work highlights the superiority of dynamic ionic-bonded 0D organic manganese halides as reversible PL switching materials in rewritable luminescent paper, high-security-level information printing, storage and protection technologies, and so forth.

0D hybrid indium halides with highly efficient intrinsic broadband light emissions.

Two new zero-dimensional (0D) hybrid indium halides of [H2DMP]2InX7·2H2O (X = Cl, Br) were designed based on [InX6]3- octahedra as optically active centers. Remarkably, these 0D halides display intrinsic broadband yellow-orange light emissions with highest quantum yield of 58.53% exceeding all previously reported 0D indium halides.