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.

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.

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.

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.

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.

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.

Zero-Dimensional Hybrid Indium Halides with Efficient and Tunable White-Light Emissions.

Two-dimensional hybrid lead perovskites have attracted a great deal of attention in white-light-emitting diodes, but the serious toxicity of Pb2+ and the limited photoluminescence quantum yield (PLQY) still restrict further optoelectronic application. To address these issues, a new combining photon strategy was proposed to achieve highly efficient broadband white-light emission in a new family of zero-dimensional (0D) indium halides based on an [InCl6]3- octahedron. Remarkably, these 0D halides display dual-band white-light emission derived from the synergistic work of blue- and yellow-light-emitting bands, which can be ascribed to the radiative recombination of bound excitons in organic cations and self-trapped excitons in inorganic anions, respectively, based on spectroscopy and theoretical studies. In-depth first-principles calculation demonstrates that the increased structural deformability effectively improves the PLQY from 7.01% to 18.56%. As a proof of concept, this work provides a profound understanding for advancing the rational design of novel single-component 0D lead-free halides as high-performance white-light emitters.

Ultra-Sensitive, Selective and Repeatable Fluorescence Sensor for Methanol Based on a Highly Emissive 0D Hybrid Lead-Free Perovskite.

A convenient and rapid detection method for methanol in ethanol remains a major challenge due to their indistinguishable physical properties. Herein, a novel fluorescence probe based on perovskite was successfully designed to overcome this bottleneck. We report a new zero-dimensional (0D) hybrid perovskite of [MP]2 Inx Sb1-x Cl7 ⋅ 6 H2 O (MP=2-methylpiperazine) displaying an unusual green light emission with near-unity photoluminescence quantum yield. Remarkably, this 0D perovskite exhibits reversible methanol-response luminescence switching between green and yellow color but fail in any other organic vapors. Even for blended alcohol solutions, the luminescent probe exhibits excellent sensing performance with multiple superiorities of rapid response time (30 s) and ultra-low detection limit (40 ppm), etc. Therefore, this 0D perovskite can be utilized as a perfect fluorescence probe to detect traces of methanol from ethanol with ultrahigh sensitivity, selectivity and repeatability. To the best of our knowledge, this work represents the first perovskite as fluorescence probe for methanol with wide potential in environmental monitoring and methanol detection, etc.

Centimeter-sized lead-free iodide-based hybrid double perovskite single crystals for efficient X-ray photoresponsivity.

Hybrid organic-inorganic lead halide perovskites (HOIPs) possess significant photoelectric characteristics for solar energy conversion, but the presence of lead causes issues for eco-friendly applications. Halide double perovskites represent a green option for application in the optoelectronic field, especially X-ray detection systems. Despite the great efforts, the exploration of large-size lead-free iodide-based hybrid double perovskite single crystals for X-ray detection has been unsuccessful. Herein, we demonstrate that a large single crystal of the 2D (two-dimensional) semiconducting perovskite (C6H16N2)2CuBiI8·0.5H2O can serve as an X-ray detection candidate. A perovskite crystal, as large as 35 × 31 × 3 mm3, was grown using a low-cost, simple cooling solution approach. To the best of our knowledge, this is the first time a centimeter-sized 2D BiCu iodide double perovskite single crystal has been used for X-ray detection. The perovskite crystal exhibited unique properties for X-ray detection, such as a significant X-ray absorption coefficient, considerable µτ product, and low trap density. Moreover, X-ray detection with a sensitivity of 5.51 µC Gyair-1 cm-2 was achieved based on a single crystal. This work opens new ways to explore specially designed organic cations for stabilizing 2D HOIPs that show great potential in optoelectronics.

Zero-dimensional Hybrid Antimony Halide with Intrinsic Cyan Light Emission.

Recently, zero-dimensional (0D) hybrid metal halides have attracted intensive attention with wide applications in solid-state lighting and display diodes. Herein, by using a facile wet-chemistry method, we prepared one new 0D hybrid antimony halide of [HMHQ]2 SbCl5 ⋅ 2H2 O (MHQ=2-methyl-8-hydroxyquinoline) based on the discrete [SbCl5 ]2- unit. Remarkably, the bulk crystals of [HMHQ]2 SbCl5 ⋅ 2H2 O exhibit strong cyan light emission with a promising photoluminescence quantum yield (PLQY) of 18.92%. Systematical studies disclose that the cyan emission is mainly derived from the radiative recombination within conjugated organic cation. Benefiting from the promising luminescent performance, this 0D antimony halide can be utilized as an excellent down-conversion light emitting luminescent material to assemble white light-emitting diodes with high color rendering index (CRI) of 90.2.

Bulk Mn2+ Doped 1D Hybrid Lead Halide Perovskite with Highly Efficient, Tunable and Stable Broadband Light Emissions.

Mn2+ doped colloidal three-dimensional (3D) lead halide perovskite nanocrystal (PNC) has attracted intensive research attention; however, the low exciton binding energy and fatal optical instability of 3D PNC seriously hinder the optoelectronic application. Therefore, it remains significant to explore new stable host perovskite with strongly bound exciton to realize more desirable luminescent property. In this work, we utilized bulk one-dimensional (1D) hybrid perovskite of [AEP]PbBr5 ⋅ H2 O (AEP=N-aminoethylpiperazine) as structural platform to rationally optimize the luminescent property by a controllable Mn2+ doping strategy. Significantly, the series of Mn2+ -doped 1D [AEP]PbBr5 ⋅ H2 O show enhanced energy transfer efficiency from the strongly bound excitons of host material to 3d electrons of Mn2+ ions, resulting in tunable broadband light emissions from weak yellow to strong red spectral range with highest photoluminescence quantum yield up to 28.41 %. More importantly, these Mn2+ -doped 1D perovskites display ultrahigh structural and optical stabilities in humid atmosphere, water and high temperature exceeding the conventional 3D PNC. Combined highly efficient, tunable and stable broadband light emissions enable Mn2+ -doped 1D perovskite as excellent down-converting phosphor showcasing the potential application in white light emitting diode. This work not only provides a profound understanding of low-dimensional perovskites but also opens a new way to rationally design high-performance broadband light emitting perovskites for solid-state lighting and displaying devices.

Dynamic changes and influencing factors of HIV-1 DNA load in HIV-1 infected individuals under antiretroviral therapy / 中华流行病学杂志

Objective: To analyze the dynamic changes and influencing factors of HIV-1 DNA load in HIV-1 infected individuals under antiretroviral therapy (ART) in Dehong Dai and Jingpo autonomous prefecture, Yunnan province, and provide information support for the clinical use of HIV-1 DNA quantitative detection. Methods: The HIV infection cases in recent infection cohort from Dehong Center for Disease Control and Prevention during 2009-2018 were selected as study subjects. The dynamic curve of HIV-1 DNA load varrying with time was generated and logistic regression analysis was conducted to identify the risk factors for HIV-1 load in the recent follow up after ART and statistical analysis was performed by using SPSS 17.0. Results: Among the 113 HIV infection cases detected from the recent infection cohort, the recent HIV infection rate were 49.6%(56/113) males, sexual transmission cases and drug injection transmission cases accounted for 53.1% (60/113), 80.5% (91/113) and 19.5% (22/113), respectively. The dynamic changes curve showed that HIV-1 DNA load was relatively high (>800 copies /106 PBMCs) before ART, and droped rapidly (<400 copies /106 PBMCs) after ART for 1 year. However, HIV-1 DNA load decreased insignificantly from the second year of ART, and remained to be 269 copies/106 PBMCs after ART for 6 years. Univariable logistic regression analysis indicated that OR (95%CI) of CD8, CD4/CD8 and HIV-1 DNA load were 1.00 (1.00-1.00), 0.30 (0.09-1.05) and 1.01 (1.00-1.01), respectively. Multivariable logistic regression analysis showed that OR value of HIV-1 DNA load base was 1.00 (1.00-1.01). Conclusions: HIV-1 DNA load decreased significantly in the first year of ART, then remained stable for years. HIV-1 DNA load base was the key factor associated with the decrease of HIV-1 DNA load, the lower the HIV-1 DNA load base, the lower HIV-1 DNA load. Therefore, earlier ART can contribute to the decrease of HIV-1 DNA load.

Three-Dimensional Cuprous Iodide Framework with Intrinsic Broadband Red-to-Near-Infrared Light Emission.

Herein, a new organic-inorganic hybrid cuprous iodide of [(Me)2-DABCO]Cu6I8 was prepared and structurally characterized with a novel three-dimensional (3D) [Cu6I8]2- framework. Significantly, this 3D cuprous iodide displays infrequent broadband red-to-near-infrared light emission (600-1000 nm) stemming from the radiative recombination of self-trapped excitons.

Enhancement of the photoluminescence efficiency of hybrid manganese halides through rational structural design.

Five new zero-dimensional hybrid manganese halides based on discrete [MnCl4]2- tetrahedrons were prepared and used as highly efficient green-light emitters. Through rational management of organic cations to tailor the MnMn separation distances between neighboring [MnCl4]2- tetrahedrons, the photoluminescence quantum yield increased significantly from 7.98% to 81.11%.

Combining Dual-Light Emissions to Achieve Efficient Broadband Yellowish-Green Luminescence in One-Dimensional Hybrid Lead Halides.

In recent years, low-dimensional lead halides have emerged as some of most attractive photoelectric materials due to their intrinsic broadband emissions with a potential application in white-light emitting diodes. To achieve the desired performance, tremendous research has emphasized the modulation of inorganic components as optical centers; however, less work has paid attention to the direct contribution of the organic components. Herein, we successfully assembled two new hybrid lead halides of [H2BPP]Pb2X6 (X = Br, 1, and Cl, 2) containing one-dimensional double [Pb2X6]2- chains using optically active 1,3-bis(4-pyridyl)-propane (BPP) as an organic cation. Under UV-light excitation, compounds 1 and 2 exhibit broadband yellowish-green emissions, which were verified by promising photoluminescence quantum efficiencies (PLQEs) of 8.10% and 4.84%, respectively. The broadband light emissions are derived from the combination of dual higher-energy blue and lower-energy yellow light spectra, which can be attributed to the individual contributions of the organic and inorganic components, respectively, according to the time-resolved and temperature-dependent emission spectra as well as theoretical calculations. This work proves the great contribution of organic components to the photophysical properties and provides a new design strategy to realize broadband light emission by rationally combining the dual-emitting properties of different assembly blocks.