Exosome-derived circUPF2 enhances resistance to targeted therapy by redeploying ferroptosis sensitivity in hepatocellular carcinoma.

BACKGROUND: Advanced hepatocellular carcinoma (HCC) can be treated with sorafenib, which is the primary choice for targeted therapy. Nevertheless, the effectiveness of sorafenib is greatly restricted due to resistance. Research has shown that exosomes and circular RNAs play a vital role in the cancer's malignant advancement. However, the significance of exosomal circular RNAs in the development of resistance to sorafenib in HCC remains uncertain. METHODS: Ultracentrifugation was utilized to isolate exosomes (Exo-SR) from the sorafenib-resistant HCC cells' culture medium. Transcriptome sequencing and differential expression gene analysis were used to identify the targets of Exo-SR action in HCC cells. To identify the targets of Exo-SR action in HCC cells, transcriptome sequencing and analysis of differential expression genes were employed. To evaluate the impact of exosomal circUPF2 on resistance to sorafenib in HCC, experiments involving gain-of-function and loss-of-function were conducted. RNA pull-down assays and mass spectrometry analysis were performed to identify the RNA-binding proteins interacting with circUPF2. RNA immunoprecipitation (RIP), RNA pull-down, electrophoretic mobility shift assay (EMSA), immunofluorescence (IF) -fluorescence in situ hybridization (FISH), and rescue assays were used to validate the interactions among circUPF2, IGF2BP2 and SLC7A11. Finally, a tumor xenograft assay was used to examine the biological functions and underlying mechanisms of Exo-SR and circUPF2 in vivo. RESULTS: A novel exosomal circRNA, circUPF2, was identified and revealed to be significantly enriched in Exo-SR. Exosomes with enriched circUPF2 enhanced sorafenib resistance by promoting SLC7A11 expression and suppressing ferroptosis in HCC cells. Mechanistically, circUPF2 acts as a framework to enhance the creation of the circUPF2-IGF2BP2-SLC7A11 ternary complex contributing to the stabilization of SLC7A11 mRNA. Consequently, exosomal circUPF2 promotes SLC7A11 expression and enhances the function of system Xc- in HCC cells, leading to decreased sensitivity to ferroptosis and resistance to sorafenib. CONCLUSIONS: The resistance to sorafenib in HCC is facilitated by the exosomal circUPF2, which promotes the formation of the circUPF2-IGF2BP2-SLC7A11 ternary complex and increases the stability of SLC7A11 mRNA. Focusing on exosomal circUPF2 could potentially be an innovative approach for HCC treatment.

Vertically Oriented Quasi-2D Perovskite Grown In-Situ by Carbonyl Array-Synergized Crystallization for Direct X-Ray Detectors.

Quasi-2D perovskite quantum wells are increasingly recognized as promising candidates for direct-conversion X-ray detection. However, the fabrication of oriented and uniformly thick quasi-2D perovskite films, crucial for effective high-energy X-ray detection, is hindered by the inherent challenges of preferential crystallization at the gas-liquid interface, resulting in poor film quality. In addressing this limitation, a carbonyl array-synergized crystallization (CSC) strategy is employed for the fabrication of thick films of a quasi-2D Ruddlesden-Popper (RP) phase perovskite, specifically PEA2MA4Pb5I16. The CSC strategy involves incorporating two forms of carbonyls in the perovskite precursor, generating large and dense intermediates. This design reduces the nucleation rate at the gas-liquid interface, enhances the binding energies of Pb2+ at (202) and (111) planes, and passivates ion vacancy defects. Consequently, the construction of high-quality thick films of PEA2MA4Pb5I16 RP perovskite quantum wells is achieved and characterized by vertical orientation and a pure well-width distribution. The corresponding PEA2MA4Pb5I16 RP perovskite X-ray detectors exhibit multi-dimensional advantages in performance compared to previous approaches and commercially available a-Se detectors. This CSC strategy promotes 2D perovskites as a candidate for next-generation large-area flat-panel X-ray detection systems.

A validated LC-MS/MS method for determination of six Anti-SARS-CoV-2 drugs in plasma and its application for a pharmacokinetic study in rats.

Antiviral treatment for COVID-19 is considered an effective tool in reducing the rate of severe cases and deaths. As of June 2023, a total of six small molecule antiviral drugs have been conditionally approved for marketing by the National Medical Products Administration (NMPA) within China. In this study, a method of HPLC-MS/MS was established and validated for the determination of six small molecule antiviral drugs in plasma using Lamivudine as an internal standard. The chromatographic separation was performed using gradient elution with an ACE 3 C18-PFP column (3.0 mm × 150 mm, 3 µm), and the mobile phase consisted of deionized water and acetonitrile/water (90:10, v/v), both with 10 mmol/L of ammonium acetate and 0.1 % ammonium hydroxide added. Quantitative analysis of the six small molecule drugs was carried out through selective reaction monitoring based on the positive ion spray ionization mode. The method exhibited excellent precision, accuracy, recovery, and linearity, and it was used to determine the pharmacokinetic characteristics in rats. Our work not only established a bioanalytical method for six small molecule antiviral drugs but also provided scientific references for clinical pharmacokinetic studies.

Ammonia Electrosynthesis from Nitrate Using a Ruthenium-Copper Cocatalyst System: A Full Concentration Range Study.

Electrochemical synthesis of ammonia via the nitrate reduction reaction (NO3RR) has been intensively researched as an alternative to the traditional Haber-Bosch process. Most research focuses on the low concentration range representative of the nitrate level in wastewater, leaving the high concentration range, which exists in nuclear and fertilizer wastes, unexplored. The use of a concentrated electrolyte (≥1 M) for higher rate production is hampered by poor hydrogen transfer kinetics. Herein, we demonstrate that a cocatalytic system of Ru/Cu2O catalyst enables NO3RR at 10.0 A in 1 M nitrate electrolyte in a 16 cm2 flow electrolyzer, with 100% faradaic efficiency toward ammonia. Detailed mechanistic studies by deuterium labeling and operando Fourier transform infrared (FTIR) spectroscopy allow us to probe the hydrogen transfer rate and intermediate species on Ru/Cu2O. Ab initio molecular dynamics (AIMD) simulations reveal that adsorbed hydroxide on Ru nanoparticles increases the density of the hydrogen-bonded water network near the Cu2O surface, which promotes the hydrogen transfer rate. Our work highlights the importance of engineering synergistic interactions in cocatalysts for addressing the kinetic bottleneck in electrosynthesis.

Outcomes of Robotic Versus Laparoscopic Pancreatoduodenectomy Following Learning Curves of Surgeons: A Multicenter Study on 2255 Patients.

OBJECTIVE: This study aimed to compare robotic pancreatoduodenectomy (RPD) with laparoscopic pancreatoduodenectomy (LPD) in operative and oncologic outcomes. BACKGROUND: Previous studies comparing RPD with LPD have only been carried out in small, single-center studies with variable quality. METHODS: Consecutive patients from nine centers in China who underwent RPD or LPD between 2015 and 2022 were included. A 1:1 propensity score matching (PSM) was used to minimize bias. RESULTS: Of the 2,255 patients, 1158 underwent RPD and 1097 underwent LPD. Following PSM, 1006 patients were enrolled in each group. The RPD group had significantly shorter operative time (270.0 vs. 305.0 minutes, P<0.001), lower intraoperative blood transfusion rate (5.9% vs. 12.0%, P<0.001), lower conversion rate (3.8% vs. 6.7%, P=0.004), and higher vascular reconstruction rate (7.9% vs. 5.6%, P=0.040) than the LPD group. There were no significant differences in estimated blood loss, postoperative length of stay, perioperative complications, and 90-day mortality. Patients who underwent vascular reconstruction had similar outcomes between the two groups, although they had significantly lower estimated blood loss (300.0 vs. 360.0 mL; P=0.021) in the RPD group. Subgroup analysis on pancreatic ductal adenocarcinoma (PDAC) found no significant differences between the two groups in median recurrence-free survival (14.3 vs. 15.3 mo, P=0.573) and overall survival (24.1 vs. 23.7 mo, P=0.710). CONCLUSIONS: In experienced hands, both RPD and LPD are safe and feasible procedures with similar surgical outcomes. RPD had the perioperative advantage over LPD especially in vascular reconstruction. For PDAC patients, RPD resulted in similar oncological and survival outcomes as LPD.

Significant Enhancement of Circular Polarization in Light Emission through Controlling Helical Pitches of Semiconductor Nanohelices.

Circularly polarized light emission (CPLE) can be potentially applied to three-dimensional displays, information storage, and biometry. However, these applications are practically limited by a low purity of circular polarization, i.e., the small optical dissymmetry factor gCPLE. Herein, glancing angle deposition (GLAD) is performed to produce inorganic nanohelices (NHs) to generate CPLE with large gCPLE values. CdSe NHs emit red CPLE with gCPLE = 0.15 at a helical pitch (P) ≈ 570 nm, having a 40-fold amplification of gCPLE compared to that at P ≈ 160 nm. Ceria NHs emit ultraviolet-blue CPLE with gCPLE ≈ 0.06 at P ≈ 830 nm, with a 103-fold amplification compared to that at P ≈ 110 nm. Both the photoluminescence and scattering among the close-packed NHs complicatedly account for the large gCPLE values, as revealed by the numerical simulations. The GLAD-based NH-fabrication platform is devised to generate CPLE with engineerable color and large gCPLE = 10-2-10-1, shedding light on the commercialization of CPLE devices.

1-Adamantanamine Hydrochloride Resists Environmental Corrosion to Obtain Highly Efficient and Stable Perovskite Solar Cells.

Passivating the defective surface of perovskite film is a promising strategy to improve the stability and efficiency of perovskite solar cells (PSCs). Herein, 1-adamantanamine hydrochloride (ATH) is introduced to the upper surface of the perovskite film to heal the defects of the perovskite surface. The best-performance ATH-modified device has a higher efficiency (23.45%) than the champion control device (21.53%). The defects are passivated, interfacial nonradiative recombination is suppressed, and interface stress is released by the ATH deposited on the perovskite film, leading to longer carrier lifetimes and enhancement in open-circuit voltage (VOC) and fill factor (FF) of the PSCs. With obvious improvement, VOC and FF of 1.159 V and 0.796 for the control device are raised to 1.178 V and 0.826 for the ATH-modified device, respectively. Finally, during an operational stability measurement of more than 1000 h, the ATH-treated PSC exhibited better moisture resistance, thermal persistence, and light stability.

Metal-Induced Planar Chirality of Soft-Bridged Binuclear Platinum(II) Complexes: 100 % Phosphorescence Quantum Yields, Chiral Self-Sorting, and Circularly Polarized Luminescence.

PtII complexes have attracted a great deal of interest due to their rich phosphorescent properties. However, these square-planar PtII complexes are far more likely to encounter the problems of lack of metal-induced chirality and emission "aggregation-caused quenching". Herein, soft-bridged binuclear PtII complexes bearing metal-induced planar chirality were synthesized and characterized. These soft bridging ligands with smaller conjugated system would help to not only improve solubility for synthesis and enantioseparation but also introduce point chirality from amino acid for highly efficient diastereoselectivity. Furthermore, the intramolecular Pt-Pt distances could be well regulated by soft bridging ligands, and consequently the phosphorescence quantum yield up to 100 % could be achieved by shortening intramolecular Pt-Pt distance for first time. These complexes can be used as emitters in highly efficient solution-processed organic light-emitting diodes.

Application of Natural Molecules in Efficient and Stable Perovskite Solar Cells.

Perovskite solar cells (PSCs), one of the most promising photovoltaic technologies, have been widely studied due to their high power conversion efficiency (PCE), low cost, and solution processability. The architecture of PSCs determines that high PCE and stability are highly dependent on each layer and the related interface, where nonradiative recombination occurs. Conventional synthetic chemical materials as modifiers have disadvantages of being toxic and costly. Natural molecules with advantages of low cost, biocompatibility, and being eco-friendly, and have improved PCE and stability by modifying both functional layers and interface. In this review, we discuss the roles of natural molecules on PSCs devices in terms of the perovskite active layer, interface, carrier transport layers (CTLs), and substrate. Finally, the summary and outlook for the future development of natural molecule-modified PSCs are also addressed.

Multifunctional anthraquinone-sulfonic potassium salts passivate the buried interface for efficient and stable planar perovskite solar cells.

SnO2-based planar perovskite solar cells (PSCs) are considered as potential photovoltaic candidates due to their simple structures and cost-effective preparation processes. However, the extensive defects accumulated at the buried interface between perovskite and SnO2 greatly hinder the further improvement of PSC efficiency and stability. Herein, the potassium salt of anthraquinone-1,8-disulfonate (ASPS) is used as a novel multifunctional interfacial modifier to improve the carrier transport performance at the buried interface and optimize the quality of the upper perovskite light absorber layer (PVK) in PSCs. Owing to the synergistic effect of sulfonic acid groups, carbonyl groups and potassium ions in ASPS, the accumulated defects at the buried interface are passivated, the energy level arrangement of the interface is optimized, and the crystalline quality and optoelectronic properties of the PVK films are improved. As a result, the power conversion efficiency (PCE) improved significantly from 21.36% for the controlled device to 23.96% for the ASPS-modified device. Furthermore, the unencapsulated ASPS-modified device also exhibited better storage stability and thermal stability than the controlled device.

High-Efficiency CsPbI2Br Perovskite Solar Cells with over 83% Fill Factor by Synergistic Effects of a Multifunctional Additive.

All-inorganic CsPbI2Br with outstanding thermal stability and excellent photoelectric properties is considered as a promising candidate for photovoltaic applications. However, the efficiency of CsPbI2Br perovskite solar cells (PSCs) is still much lower than that of their organic-inorganic hybrid counterparts or CsPbI3-based devices. Herein, we obtained an optimized CsPbI2Br PSC (0.09 cm2) with a champion efficiency of 17.38% and a record fill factor of 83.6% by introducing potassium anthraquinone-1,8-disulfonate (DAD) in the precursor solution. The synergistic effect between the electronegative functional groups and K+ ions in the DAD structure can not only effectively regulate the crystallization growth process to improve the crystalline quality and stability of photo-active CsPbI2Br but also optimize the energy level alignment and passivate the defects to improve the carrier transport properties. The efficiency of the corresponding large-area device (5 cm × 5 cm with an active area of 19.25 cm2) reached 13.20%. Moreover, the optimized CsPbI2Br PSC exhibited negligible hysteresis and enhanced long-term storage stability as well as thermal stability. Our method produces more stable photo-active CsPbI2Br with excellent photoelectric properties for industrial applications or perovskite/silicon tandem cells.

Precise modulation strategies of 2D/3D perovskite heterojunctions in efficient and stable solar cells.

2D/3D perovskite heterojunctions exhibit promising prospects in the improvement of efficiency and stability of perovskite solar cells (PSCs). However, many challenges remain in the development of high-quality 2D/3D heterojunctions, such as a reliable pathway to control the perovskite phase and generally poor performance in inverted (p-i-n) devices, which limit their commercialization. Fortunately, many excellent works have proposed lots of strategies to solve these challenges, which have triggered a new wave of research on 2D/3D perovskite heterojunctions in recent years. In this paper, the latest research progress and the critical factors involved in the modulating mechanisms of PSCs with 2D/3D heterojunctions have been summarized and laid out systematically. The advantages of constructing 2D/3D perovskite heterojunctions in PSCs are highlighted, and the problems and related solutions of low-dimensional perovskites as passivation layers towards high-performance PSCs are also discussed in depth. Finally, the prospects of 2D/3D perovskite heterojunctions utilized in the passivation strategies to further improve the photovoltaic performance of PSCs in the future have been presented.

Nexuses Between the Chemical Design and Performance of Small Molecule Dopant-Free Hole Transporting Materials in Perovskite Solar Cells.

Perovskite solar cells (PSCs) have grabbed much attention of researchers owing to their quick rise in power conversion efficiency (PCE). However, long-term stability remains a hurdle in commercialization, partly due to the inclusion of necessary hygroscopic dopants in hole transporting materials, enhancing the complexity and total cost. Generally, the efforts in designing dopant-free hole transporting materials (HTMs) are devoted toward small molecule and polymeric HTMs, where small molecule based HTMs (SM-HTMs) are dominant due to their reproducibility, facile synthesis, and low cost. Still, the state-of-art dopant-free SM-HTM has not been achieved yet, mainly because of the knowledge gap between device engineering and molecular designs. From a molecular engineering perspective, this article reviews dopant-free SM-HTMs for PSCs, outlining analyses of chemical structures with promising properties toward achieving effective, low-cost, and scalable materials for devices with higher stability. Finally, an outlook of dopant-free SM-HTMs toward commercial application and insight into the development of long-term stability PSCs devices is provided.

Performance improvement of space-resolved extreme ultraviolet spectrometer by use of complementary metal-oxide semiconductor detectors at the Experimental Advanced Superconducting Tokamak.

Two pairs of space-resolved extreme ultraviolet (EUV) spectrometers working at 5-138 Å with different vertical observation ranges of -7 ≤ Z ≤ 19 and -18 ≤ Z ≤ 8 cm have been newly developed to observe the radial profile of impurity line emissions and to study the transport of high-Z impurity ions intrinsically existing in EAST tokamak plasmas. Both spectrometers are equipped with a complementary metal-oxide semiconductor (CMOS) detector (Andor Marana-X 4.2B-6, Oxford Instruments) with sensitive area of 13.3 × 13.3 mm2 and number of pixels equal to 2048 × 2048 (6.5 × 6.5 µm2/pixels). Compared to the currently operating space-resolved EUV spectrometers with a charge-coupled detector (CCD: 1024 × 255 pixels, 26 × 26 µm2) working at 30-520 Å, this spectrometer's performance was substantially improved by using the CMOS detector. First, the spectral resolution measured at full width at half maximum was improved in the whole wavelength range, e.g., Δλ1/2_CMOS = 0.092 Å and Δλ1/2_CCD = 0.124 Å at C VI 33.73 Å and Δλ1/2_CMOS = 0.104 Å and Δλ1/2_CCD = 0.228 Å at Mo XXXI 115.999 Å, thus enabling a more accurate analysis of spectra with complicated structure such as tungsten unresolved transition array in the range 45-65 Å. Second, the temporal resolution was largely improved due to the high-speed data acquisition system of the CMOS detector, e.g., Δt_CMOS = 15 ms/frame and Δt_CCD = 200 ms/frame at routine operation in the radial profile measurement. Third, signal saturation issues that occurred when using the old CCD sensor during impurity accumulation now disappeared entirely using the CMOS detector due to lower exposure time at high readout rates, which largely improved the observation performance in similar impurity burst events. The above-mentioned performance improvements of the space-resolved EUV spectrometer led to a rapid change in the W XXXIII (52.22 Å) radial profile during a single cycle of low-frequency sawtooth oscillation with fst = 5-6 Hz at a sufficient detector count rate.

Parameter-tuning stochastic resonance as a tool to enhance wavelength modulation spectroscopy using a dense overlapped spot pattern multi-pass cell.

The parameter-tuning stochastic resonance (SR) method can convert part of the noise energy into the signal energy to suppress the noise and amplify the signal, comparing with traditional weak periodic signal detection methods (e.g., time average method, filtering method, and correlation analysis method). In this work, the numerical calculation is conducted to find the optimal resonance parameters for applying the SR method to the wavelength modulation spectroscopy (WMS). Under the stochastic resonance state, the peak value of 2f signal (a constant concentration of CH4∼20 ppm) is effectively amplified to ∼0.0863 V, which is 3.8 times as much as the peak value of 4000-time average signal (∼0.0231 V). Although the standard deviation also increases from ∼0.0015 V(1σ) to ∼0.003 V(1σ), the SNR can be improved by 1.83 times (from ∼25.9 to ∼15.8) correspondingly. A linear spectral response of SR 2f signal peak value to raw 2f signal peak value is obtained. It suggests that the SR method is effective for enhancing photoelectric signal under strong noise background.

Gold(I) Multi-Resonance Thermally Activated Delayed Fluorescent Emitters for Highly Efficient Ultrapure-Green Organic Light-Emitting Diodes.

Acceleration of singlet-triplet intersystem crossings (ISC) is instrumental in bolstering triplet exciton harvesting of multi-resonance thermally activated delayed fluorescent (MR-TADF) emitters. This work describes a simple gold(I) coordination strategy to enhance the spin-orbit coupling of green and blue BN(O)-based MR-TADF emitters, which results in a notable increase in rate constants of the spectroscopically observed ISC process to 3×109  s-1 with nearly unitary ISC quantum yields. Accordingly, the resultant thermally-stable AuI emitters attained large values of delayed fluorescence radiative rate constant up to 1.3×105 /1.7×105  s-1 in THF/PMMA film while preserving narrowband emissions (FWHM=30-37 nm) and high emission quantum yields (ca. 0.9). The vapor-deposited ultrapure-green OLEDs fabricated with these AuI emitters delivered high luminance of up to 2.53×105  cd m-2 as well as external quantum efficiencies of up to 30.3 % with roll-offs as low as 0.8 % and long device lifetimes (LT60 ) of 1210 h at 1000 cd m-2 .

A multifunctional chemical linker in a buried interface for stable and efficient planar perovskite solar cells.

The buried interface between a perovskite (PVK) light absorbing layer and an electron transport layer (ETL) plays an utmost important role in further improving the efficiency and stability of planar perovskite solar cells (PSCs). The interfacial properties greatly affect charge transport, perovskite crystal growth, and device stability. Herein, a variable structure broad-spectrum UV-284 absorber agent 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid (HMBS) is introduced into PSCs based on SnO2 ETLs as an efficient multifunctional chemical linker to modify the buried interface properties. HMBS used to modify SnO2 can simultaneously suppress the surface trap states of ETLs, optimize the ETL/PVK interface energy level arrangement, and improve the crystallization quality of the upper perovskite films. Meanwhile, as an efficient UV absorber, HMBS can also greatly reduce the damage caused by UV light to perovskite films and thus improve the stability of devices. Consequently, HMBS-modified PSCs exhibit champion efficiencies of 23.42% (0.09 cm2) and 20.63% (1.00 cm2) along with remarkably enhanced UV stability. This work emphasizes the importance of appropriate interface treatment strategies for buried interface modification and provides an effective method for fabricating efficient and UV resistant perovskite photovoltaic devices.

Room-Temperature Phosphorescence of Pure Axially Chiral Bicarbazoles.

Ultralong room-temperature phosphorescence (RTP) is greatly important in a series of applications, but obtaining RTP from metal-free organic materials is still an enormous challenge due to the spin-forbidden nature of triplet excitons. Because of its electron-rich nature and easy derivatization, carbazole (Cz) is widely used to build organic RTP and thermally activated delayed fluorescence (TADF) materials. However, Liu et al. (Nat. Mater. 2021, 20, 175) recently demonstrated that the RTP of Cz is induced by charge traps of its isomeric impurity in commercial sources. Here, on the basis of the classical El-Sayed rule and the recently discovered intersystem crossing promotion principles (twisted structure and charge transfer), we designed and prepared highly pure (>99.9%) (R/S)-octahydro-binaphthyl-based bicarbazoles (BiCz) for high-performance RTP (ΦP = 23%; τp = 1.09 s). Interestingly, BiCz exhibited photoactivated TADF and RTP in isolated and aggregated states, respectively, and thus would be an efficient tool for rejuvenating Cz-based RTP.

[Quantitative Analysis of the Correlation Between Macrobenthos Community and Water Environmental Factors and Aquatic Ecosystem Health Assessment in the North Canal River Basin of Beijing].

Macrobenthos can reflect the cumulative effect of various ecological threats on the water environment and are closely related to the health of river ecosystems. In this study, taking the North Canal River basin, a typical basin in Beijing, as an example, ecological data from 34 stations were investigated in the summer of 2015. Characteristics of the macrobenthos communities were analyzed, and driving environmental factors were identified using typical correspondence analysis. Thresholds and response species of those driving environmental factors were conducted using the thresholds indicator taxa analysis (TITAN). In this study, the health status of the river ecosystem was evaluated by the multi-metrics method and benthic index of biotic integrity (B-IBI). The benthic community was dominated by pollution-tolerant aquatic insects and mollusks, with a low-level Shannon-wiener diversity index between 0-1.01; fluoride, biochemical oxygen demand, ammonia-nitrogen, and total phosphorus were driving environmental factors influencing the community structure of macrobenthos. Indicator species of ammonia-nitrogen were identified by the TITAN in the North Canal River basin with a threshold range of 1.09-6.94 mg·L-1; three indicator species of total phosphorus were identified with a threshold range of 0.48-1.27 mg·L-1, which were all positive response species. According to the health assessment, the river ecosystem in the North Canal River basin was generally unhealthy, and the upstream ecosystem was better than that downstream; the health conditions in the mountainous areas of Changping district were the best, whereas those in Chaoyang and central city districts were the worst. This study can provide a basis for ecological restoration and pollution control of rivers and also provide a reference for the water ecological civilization construction in other cities.

Highly Phosphorescent Planar Chirality by Bridging Two Square-Planar Platinum(II) Complexes: Chirality Induction and Circularly Polarized Luminescence.

Chiral organometallic complexes have demonstrated many potential and practical applications. However, building metal-induced chirality for square-planar complexes still remains a big challenge, because their 2D planar molecular structures are usually superimposable on their mirror images. Herein, we report a straightforward and efficient way to achieve a novel kind of planar chirality by constructing 3D double-layer molecular structures. When the achiral ligand 1,3,4-oxadiazole-2-thiol (OXT) was used to bridge two square-planar complexes, a pair of racemic R/S planar-chiral binuclear Pt(II) complexes was obtained, which could be separated by chiral high-performance liquid chromatography (HPLC). Moreover, enantiopure R,R,R or S,S,S complexes could be prepared by the use of chiral (R)-/(S)-binaphthalene-derived OXT ligands in 99% diastereoselectivity without the use of chiral HPLC. The binaphthalene groups help to ensure good solubility and a smooth amorphous thin film morphology but have little effect on the photophysical properties. The resultant complexes display strong orange-red and near-infrared phosphorescence with quantum yields of up to 83.4% and can be applied as emitters in highly efficient solution-processed organic light-emitting diodes to achieve luminance, luminance efficiency, external quantum efficiency, and an asymmetry factor of up to 3.22 × 104 cd m-2, 28.7 cd A-1, 14.3%, and 2.0 × 10-3, respectively. With a comprehensive consideration of EL efficiency and the asymmetry factor, this is the best performance among Pt(II) complex based circularly polarized OLEDs. Therefore, this work provides a new and simple strategy to build planar chirality for chiroptical and circularly polarized luminescence applications.