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Inserting an insulating layer between the charge transport layer (CTL) and quantum dot emitting layer (QDL) is widely used in improving the performance of quantum dot light-emitting diodes (QLEDs). However, the additional layer inevitably leads to energy loss and joule heat. Herein, a monolayer silane coupling agent is used to modify the said interfaces via the self-limiting adsorption effect. Because the ultrathin layers induce negligible series resistance to the device, they can partially passivate the interfacial defects on the electron transport side and help confine the electrons within the QDL on the hole transport side. These interfacial modifications can not only suppress the nonradiative recombination but also slow down the aging of the hole transport layer. The findings here underline a low-temperature adsorption-based strategy for effective interfacial modification which can be used in any layer-by-layer device structures.
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The rapid evolution of the Internet of Things has engendered increased requirements for low-cost, self-powered UV photodetectors. Herein, high-performance self-driven UV photodetectors are fabricated by designing asymmetric metal-semiconductor-metal structures on the high-quality large-area CsCu2I3 microwire arrays. The asymmetrical depletion region doubles the photocurrent and response speed compared to the symmetric structure device, leading to a high responsivity of 233 mA/W to 355 nm radiation. Notably, at 0 V bias, the asymmetric device produces an open-circuit voltage of 356 mV and drives to a short-circuit current of 372 pA; meanwhile, the switch ratio (Iph/Idark) reaches up to 103, indicating its excellent potential for detecting weak light. Furthermore, the device maintains stable responses throughout 10000 UV-light switch cycles, with negligible degradation even after 90-day storage in air. Our work establishes that CsCu2I3 is a good candidate for self-powered UV detection and thoroughly demonstrates its potential as a passive device.
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Highly efficient multi-dimensional data storage and extraction are two primary ends for the design and fabrication of emerging optical materials. Although metasurfaces show great potential in information storage due to their modulation for different degrees of freedom of light, a compact and efficient detector for relevant multi-dimensional data retrieval is still a challenge, especially in complex environments. Here, we demonstrate a multi-dimensional image storage and retrieval process by using a dual-color metasurface and a double-layer integrated perovskite single-pixel detector (DIP-SPD). Benefitting from the photoelectric response characteristics of the FAPbBr2.4I0.6 and FAPbI3 films and their stacked structure, our filter-free DIP-SPD can accurately reconstruct different colorful images stored in a metasurface within a single-round measurement, even in complex environments with scattering media or strong background noise. Our work not only provides a compact, filter-free, and noise-robust detector for colorful image extraction in a metasurface, but also paves the way for color imaging application of perovskite-like bandgap tunable materials.
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High-temperature scintillation detectors play a significant role in oil exploration. However, traditional scintillators have limited ability to meet the requirements of practical applications owing to their low thermal stability. In this study, we designed and developed a one-dimensional (1D) Cs5Cu3Cl6I2 scintillator with high thermal stability. In addition, by preparing Cs5Cu3Cl7I, we proved that the Cs5Cu3Cl6I2 scintillator exhibits high thermal stability because the bridges linking the structural units in the 1D chain structure are only formed by I- ions, which improve their structural rigidity. The scintillator has a high steady-state light yield (59,700 photons MeV-1) and exhibits the highest spatial resolution for powder-based scintillation screens (18 lp mm-1) after cyclic treatment within the temperature range of 298-423 K. The Cs5Cu3Cl6I2 scintillator allows the visualization of alloy melting, indicating that it has significant potential for application in high-temperature environments. This study provides a new perspective toward the design of scintillators with high thermal stability.
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High-efficiency electromagnetic (EM) functional materials are the core building block of high-performance EM absorbers and devices, and they are indispensable in various fields ranging from industrial manufacture to daily life, or even from national defense security to space exploration. Searching for high-efficiency EM functional materials and realizing high-performance EM devices remain great challenges. Herein, a simple solution-process is developed to rapidly grow gram-scale organic-inorganic (MAPbX3 , X = Cl, Br, I) perovskite microcrystals. They exhibit excellent EM response in multi bands covering microwaves, visible light, and X-rays. Among them, outstanding microwave absorption performance with multiple absorption bands can be achieved, and their intrinsic EM properties can be tuned by adjusting polar group. An ultra-wideband bandpass filter with high suppression level of -71.8 dB in the stopband in the GHz band, self-powered photodetectors with tunable broadband or narrowband photoresponse in the visible-light band, and a self-powered X-ray detector with high sensitivity of 3560 µC Gyair -1 cm-2 in the X-ray band are designed and realized by precisely regulating the physical features of perovskite and designing a novel planar device structure. These findings open a door toward developing high-efficiency EM functional materials for realizing high-performance EM absorbers and devices.
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Stacked 2D perovskites provide more possibilities for next generation photodetector with more new features. Compared with its excellent optoelectronic properties, the good dielectric performance of metal halide perovskite rarely comes into notice. Here, a bifunctional perovskite based photovoltaic detector capable of two wavelength demultiplexing is demonstrated. In the Black Phosphorus/Perovskite/MoS2 structured photodetector, the comprehensive utilization of the photosensitive and dielectric properties of 2D perovskite allows the device to work in different modes. The device shows normal continuous photoresponse under 405 nm, while it shows a transient spike response to visible light with longer wavelengths. The linear dynamic range, rise/decay time, and self-powered responsivity under 405 nm can reach 100, 38 µs/50 µs, and 17.7 mA W-1 , respectively. It is demonstrated that the transient spike photocurrent with long wavelength exposure is related to the illumination intensity and can coexist with normal photoresponse. Two waveband-dependent signals can be identified and used to reflect more information simultaneously. This work provides a new strategy for multispectral detection and demultiplexing, which can be used to improve data transfer rates and encrypted communications. This work mode can inspire more multispectral photodetectors with different stacked 2D materials, especially to the optoelectronic application of the wide bandgap, high dielectric photosensitive materials.
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Copper-based halide perovskites have shown great potential in lighting and photodetection due to their excellent photoelectric properties, good stability and lead-free nature. However, as an important piece of copper-based perovskites, the synthesis and application of RbCu2I3have never been reported. Here, we demonstrate the synthesis of high-quality RbCu2I3microwires (MWs) by a fast-cooling hot saturated solution method. The prepared MWs exhibit an orthorhombic structure with a smooth surface. Optical measurements show the RbCu2I3MWs have a sharp ultraviolet absorption edge with 3.63 eV optical band gap and ultra-large stokes shift (300 nm) in photoluminescence. The subsequent photodetector based on a single RbCu2I3MW shows excellent ultraviolet detection performance. Under the 340 nm illumination, the device shows a specific detectivity of 5.0 × 109Jones and a responsivity of 380 mA·W-1. The synthesis method and physical properties of RbCu2I3could be a guide to the future optoelectronic application of the new material.
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Objective To investigate the clinical characteristics of drug-induced liver injury caused by anti-tuberculosis drugs in newly treated pulmonary tuberculosis patients with hepatitis B virus (HBV). Methods A total of 133 patients with pulmonary tuberculosis and HBV who were treated in Zhuzhou Central Hospital from January 2018 to early January 2022 were selected, and all were treated with conventional anti-tuberculosis 2HRZE/4HR regimen. According to the liver injury, the patients were divided into liver injury group and no liver injury group. Univariate analysis was used to analyze the related factors of liver injury caused by anti-tuberculosis drugs, and multivariate logistic regression analysis was used to analyze the independent risk factors of liver injury caused by anti-tuberculosis drugs. Results Among 133 cases of newly treated pulmonary tuberculosis patients with HBV, 24 cases had liver injury caused by anti-tuberculosis drugs, accounting for 18.05%; 109 patients had no liver injury caused by anti-tuberculosis drugs, accounting for 81.95%. Univariate analysis showed that there were significant differences in smoking history, drinking history, diabetes history, hypertension history, anti-tuberculosis treatment plan, malnutrition, and use of hepatoprotective drugs between the liver injury group and the no liver injury group (P<0.05). Multivariate logistic regression analysis showed that smoking history, drinking history, diabetes history, hypertension history, PZA-containing regimen, malnutrition, and no use of hepatoprotective drugs were independent risk factors for liver injury caused by anti-tuberculosis drugs. Conclusion Smoking history, drinking history, diabetes history, hypertension history, PZA-containing regimen, malnutrition, and no use of hepatoprotective drugs are the risk factors for drug-induced liver injury caused by anti-tuberculosis drugs in newly treated pulmonary tuberculosis patients with HBV.
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OBJECTIVE To establish a method for the simultaneous determination of 10 rhubarb anthraquinones in Compound gentian sodium bicarbonate tablets and the content of rhaponticin,which are the characteristic components of artifacts,and to use the method to evaluate the quality of compound preparation containing Rheum officinale. METHODS The ultra-performance liquid chromatography (UPLC) method was adopted to determine the contents of 10 rhubarb anthraquinones (aloe-emodin-8-O-glucoside, rheinic acid-8-O-β-D-glucoside,emodin-8-O-glucoside,chrysophanol-8-O-β-D-glucoside,emodin monomethyl ether-8-O-β-D-glucoside, aloe-emodin,rheinic acid,emodin,chrysophanol,emodin monomethyl ether) and rhaponticin in 40 batches of Compound gentian sodium bicarbonate tablets from 8 manufacturers. The determination was performed on the Agilent Eclipse Plus C18 column with a mobile phase consisted of acetonitrile-0.1% phosphoric acid solution (gradient elution) at a flow rate of 0.3 mL/min; the column temperature was set at 30 ℃ ,and the injection volume was 5 μL. Combining principal component analysis and cluster analysis to synthesize the results of content determination,the quality of samples from different manufacturers was evaluated. RESULTS All of above 11 components showed favorable linear relationships with peak areas in their respective mass concentration ranges (r≥0.999 3),with RSDs of precision,repeatability and stability 296261547@qq.com less than 3% (n=6); average sample recoveries ranged 96.82%-98.92% (RSD≤1.74%,n=6); their contents were 0971-8247794。E-mail:304436784@qq.com 0.011 7-0.252 0,0-0.323 3,0.131 3-1.236 6,0.081 1-1.056 2,0.015 2-0.189 8,0.001 8-0.152 3,0-0.255 2,0.001 9-0.223 4,0.054 3-0.303 0,0.022 7-0.172 2,0-2.835 9 mg/g,respectively. The cumulative variance contribution of the first three principal components was 95.533%; the 40 batches of samples can be clustered into 4 categories:samples from enterprises a and d were in a category of their own,samples from enterprises f,b,g and e were in a category,and samples from enterprises c and h were in a category. There were large differences in the content of rhubarb anthraquinone in the samples from 8 manufacturers,and rhaponticin was only detected in the sample from one enterprise. CONCLUSIONS Established UPLC method is stable and reliable; it can be used for the content determination of 10 rhubarb anthraquinones and rhaponticin in Compound gentian sodium bicarbonate tablets.
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Lead-free perovskite has attracted great attention in realizing high-performance optoelectronic devices due to their excellent atmospheric stability and nontoxic characteristics. Although a pronounced ion migration effect has been observed in this new class of materials, its potential in enhancing the overall device performance is yet to be fully explored. In this work, we studied the effect of ion migrations on the carrier transport behavior and found that the recoverable migration process can contribute to enhancing the on/off ratio in a lead-free CsCu2I3 single-crystal microrod-based photodetector. In detail, we synthesized CsCu2I3 single-crystal microrods via an in-plane self-assembly supersaturated crystallization approach. These microrods with well-defined morphologies were then used to construct ultraviolet (UV)-band photodetectors, which outperform most reported lead-free perovskite photodetectors based on individual single crystals. Simultaneously, ion migration can result in asymmetric band bending in the two-terminal device, as confirmed by surface potential profiling with Kelvin probe force microscopy (KPFM). Such an effect can be harnessed to increase the on/off ratio by almost an order of magnitude. Furthermore, the lead-free CsCu2I3 single crystal exhibits excellent thermal and air stabilities. These findings demonstrate that the CsCu2I3 single-crystal microrods can be used in stable and efficient photodetection, and the ion migration effect can potentially be utilized for improving the optoelectronic performance of lead-free devices.
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Aqueous electrochromic battery (ECB) is a multifunctional technology that shows great potential in various applications including energy-saving buildings and wearable batteries with visible energy levels. However, owing to the mismatch between traditional electrochromic materials and the electrolyte, aqueous ECBs generally exhibit poor cycling stability which bottlenecks their practical commercialization. Herein, we present an ultrastable electrochromic system composed of lithium titanate (Li4Ti5O12, LTO) electrode and Al3+/Zn2+ hybrid electrolyte. The fully compatible system exhibits excellent redox reaction reversibility, thus leading to extremely high cycling stabilities in optical contrast (12â¯500 cycles with unnoticeable degradation) and energy storage (4000 cycles with 82.6% retention of capacity), superior electrochromic performances including high optical contrast (â¼74.73%) and fast responses (4.35 s/7.65 s for bleaching/coloring), as well as excellent discharge areal capacity of 151.94 mAh m-2. The extraordinary cycling stability can be attributed to the robust [TiO6] octahedral frameworks which remain chemically active even upon the gradual substitution of Li+ with Al3+ in LTO over multiple operation cycles. The high-performance electrochromic system demonstrated here not only makes the commercialization of low-cost, high-safety aqueous-based electrochromic devices possible but also provides potential design guidance for LTO-related materials used in aqueous-based energy storage devices.
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Phytochemical investigation on the whole plant of Chloranthus multistachys pei (Chloranthaceae) afforded three pairs of new sesquiterpene enantiomers (+)/(-)-chlorantene M [(+)/(-)-1], (+)/(-)-chlorantene M1 [(+)/(-)-2] and (+)/(-)-chlorantene N [(+)/(-)-3]. The structures of new compounds were determined through spectroscopic techniques (HR-ESI-MS, 1 D and 2 D NMR), besides, their absolute and relative configurations were established by using Single-crystal X-ray diffraction analysis and CD spectrum. The anti-inflammatory potential of all compounds was evaluated by applying LPS induced RAW 264.7 macrophage inflammatory model, and the results were that none of these compounds showed activity (IC50 > 100 µM).[Formula: see text].
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Magnoliopsida , Sesquiterpenos , Antiinflamatorios/química , Antiinflamatorios/farmacología , Lipopolisacáridos/farmacología , Magnoliopsida/química , Estructura Molecular , Fitoquímicos , Sesquiterpenos/química , Sesquiterpenos/farmacologíaRESUMEN
Interfacial quality of functional layers plays an important role in the carrier transport of sandwich-structured devices. Although the suppression of interface states is crucial to the overall device performance, our understanding on their formation and annihilation mechanism via direct characterization is still quite limited. Here, we present a thorough study on the interface states present in the electron transport layer (ETL) of blue quantum dot (QD) light-emitting diodes (QLEDs). A ZnO/ZnMgO bilayer ETL is adopted to enhance the electron injection into blue QDs. By probing the ETL band structure with photoelectron spectroscopy, we discover that substantial band bending exists at the ZnO/ZnMgO interface, elucidating the presence of a high density of interface states which hinder electron transport. By inserting a ZnO@ZMO interlayer composed of mixed ZnO and ZnMgO nanoparticles, the band bending and thus the interface states are observed to reduce significantly. We attribute this to the hybrid surface properties of ZnO@ZMO, which can annihilate the surface states of both the ZnO and ZnMgO layers. The introduction of a bridging layer has led to â¼40% enhancement in the power efficiency of blue QLEDs and noticeable performance boosts in green and red QLEDs. The findings here demonstrate a direct observation of interface states via detailed band structure studies and outline a potential pathway for eliminating these states for better performances in sandwich-structured devices.
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Water-soluble red afterglow imaging agents based on ecofriendly nanomaterials have potential application in time-gated afterglow bioimaging due to their larger penetration depth and nondurable excitation. Herein, red afterglow imaging agents consisted of Rhodamine B (RhB) and carbon nanodots (CNDs) have been designed and demonstrated. In these agents, CNDs act as energy donors, and RhB acts as an energy acceptor. Both of them are confined into a hydrophilic silica shell to form a CNDs-RhB@silica nanocomposite. The phosphorescence emission spectrum of the CNDs and the absorption spectrum of the RhB match well, and efficient energy transfer from the CNDs to the RhB via Förster resonant energy transfer process can be achieved, with a transfer efficiency can reach 99.2%. Thus, the as-prepared nanocomposite can emit a red afterglow in aqueous solution, and the afterglow spectrum of CNDs-RhB@silica nanocomposite can extend to the first near-infrared window (NIR-I). The luminescence lifetime and afterglow quantum yield (QY) of the CNDs-RhB@silica can reach 0.91 s and 3.56%, respectively, which are the best results in red afterglow region. Time-gated in vivo afterglow imaging has been demonstrated by using the CNDs-RhB@silica as afterglow agents.
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Carbono , Nanoestructuras , Transferencia de Energía , Luminiscencia , AguaRESUMEN
With many advantages including superior color saturation and efficiency, quantum dot light-emitting diodes (QLEDs) are considered a promising candidate for the next-generation displays. Emission uniformity over the entire device area is a critical factor to the overall performance and reliability of QLEDs. In this work, we performed a thorough study on the origin of dark spots commonly observed in operating QLEDs and developed a strategy to eliminate these defects. Using advanced cross section fabrication and imaging techniques, we discovered the occurrence of voids in the organic hole transport layer and directly correlated them to the observed emission nonuniformity. Further investigations revealed that these voids are thermal damages induced during the subsequent thermal deposition of other functional layers and can act as leakage paths in the device. By inserting a thermo-tolerant 1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile (HATCN) interlayer with an optimized thickness, the thermally induced dark spots can be completely suppressed, leading to a current efficiency increase by 18%. We further demonstrated that such a thermal passivation strategy can work universally for various types of organic layers with low thermal stability. Our findings here provide important guidance in enhancing the performances and reliability of QLEDs and also other sandwich-structured devices via the passivation of heat-sensitive layers.
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With repeated silica gel, octadecyl silica(ODS), and Sephadex LH-20 column chromatography, normal-phase and reverse-phase high performance liquid chromatography(HPLC), etc., a pair of new enantiomers and 5 known compounds were separated from the 95% ethanol extract of Chloranthus multistachys. These compounds were identified by the nuclear magnetic resonance spectroscopy(including 1 D-NMR and 2 D-NMR), single-crystal X-ray diffraction, circular dichroism(CD) spectroscopy, mass spectrometry(MS), and some other methods as(1R,4R,5R,8S,10R)-chloraeudolide H(1 a),(1S,4S,5S,8R,10S)-chloraeudolide H(1 b), hydroxyisogermafurenolide(2), 4α-hydroxy-5α,8ß(H)-eudesm-7(11)-en-8,12-olide(3), chloraniolide A(4), chlorantene D(5), 4α,8ß-dihydroxy-5α(H)-eudesm-7(11)-en-8,12-olide(6). Compounds 1 a and 1 b are a pair of new eudesmane-type sesquiterpene enantiomers, and compounds 2-4 were isolated from C. multistachys for the first time.
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Sesquiterpenos , Cromatografía Líquida de Alta Presión , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Estructura Molecular , EstereoisomerismoRESUMEN
The genus Chloranthus has 13 species and 5 varieties in China, which can be found in the southwest and northeast regions. Phytochemical studies on Chloranthus plants have reported a large amount of terpenoids, such as diterpenoids, sesquiterpenoids, and sesquiterpenoid dimers. Their anti-inflammation, anti-tumor, antifungal, antivirus, and neuroprotection activities have been confirmed by previous pharmacological research. Herein, research on the chemical constituents from Chloranthus plants and their biological activities over the five years was summarized to provide scientific basis for the further development and utilization of Chloranthus plants.
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Diterpenos , Sesquiterpenos , Fitoquímicos/farmacología , Plantas , Sesquiterpenos/farmacología , TerpenosRESUMEN
Colloidal all-inorganic perovskites nanocrystals (NCs) have emerged as a promising material for display and lighting due to their excellent optical properties. However, blue emissive NCs usually suffer from low photoluminescence quantum yields (PLQYs) and poor stability, rendering them the bottleneck for full-color all-perovskite optoelectronic applications. Herein, a facile approach is reported to enhance the emission efficiency and stability of blue emissive perovskite nano-structures via surface passivation with potassium bromide. By adding potassium oleate and excess PbBr2 to the perovskite precursor solutions, potassium bromide-passivated (KBr-passivated) blue-emitting (≈450 nm) CsPbBr3 nanoplatelets (NPLs) is successfully synthesized with a respectably high PLQY of 87%. In sharp contrast to most reported perovskite NPLs, no shifting in emission wavelength is observed in these passivated NPLs even after prolonged exposures to intense irradiations and elevated temperature, clearly revealing their excellent photo- and thermal-stabilities. The enhancements are attributed to the formation of K-Br bonding on the surface which suppresses ion migration and formation of Br-vacancies, thus improving both the PL emission and stability of CsPbBr3 NPLs. Furthermore, all-perovskite white light-emitting diodes (WLEDs) are successfully constructed, suggesting that the proposed KBr-passivated strategy can promote the development of the perovskite family for a wider range of optoelectronic applications.
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Seven eudesmane-type sesquiterpenoids, including three pairs of racemic compounds (1a-3a and 1b-3b) and a sesquiterpenoid lactone (4), were obtained from the roots of Chloranthus serratus. The structures of these sesquiterpenoids were characterized based on spectroscopic analyses, ECD calculations, and X-ray diffraction experiment. Neuroprotection assays of the isolated eudesmane-type sesquiterpenoids were conducted on H2O2 damaged PC12 cells. At the concentration of 10 µM, compounds 1b and 4 increased cell viability from 54.8 ± 3.3% to 76.8 ± 2.3 and 72.7 ± 8.2%, respectively.
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Magnoliopsida/química , Fármacos Neuroprotectores/farmacología , Sesquiterpenos de Eudesmano/farmacología , Animales , China , Estructura Molecular , Fármacos Neuroprotectores/aislamiento & purificación , Células PC12 , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Raíces de Plantas/química , Ratas , Sesquiterpenos de Eudesmano/aislamiento & purificaciónRESUMEN
Eight sesquiterpenes were isolated and purified from the ethanol extract of Chloranthus henryi by column chromatographies over silica gel, ODS and Sephadex LH-20,and preparative HPLC. Their chemical structures were established by spectral data and physiochemical properties as(1S,6S,8S,10R)-8-ethoxy-10-methoxychlomultin C(1),tianmushanol(2),multistalide A(3),myrrhterpenoid N(4),1α,9α-dihydroxy-8,12-expoxy-eudesma-4,7,11-trien-6-one(5),4ß,10α-aromadendranediol(6),oplopanone(7),10α-hydroxycadinan-4-en-3-one(8). Among them, compound(1) was a new compound, and compounds 2-8 were isolated from Chloranthus henryi for the first time.