Plasmonic Bound States in the Continuum Metasurface-Semiconductor-Metal Architecture Enables Efficient Hot-Electron-Based Photodetector.

Plasmonic hot-electron-based photodetectors (HEB-PDs) have received widespread attention for their ability to realize effective carrier collection under sub-bandgap illumination. However, due to the low hot electron emission probability, most of the existing HEB-PDs exhibit poor responsivity, which significantly restricts their practical applications. Here, by employing the binary-pore anodic alumina oxide template technique, we proposed a compact plasmonic bound state in continuum metasurface-semiconductor-metal-based (BIC M-S-M) HEB-PD. The symmetry-protected BIC can manipulate a strong gap surface plasmon in the stacked M-S-M structure, which effectively enhances light-matter interactions and improves the photoresponse of the integrated device. Notably, the optimal M-S-M HEB-PD with near-unit absorption (∼90%) around 800 nm delivers a responsivity of 5.18 A/W and an IPCE of 824.23% under 780 nm normal incidence (1 V external bias). Moreover, the ultrathin feature of BIC M-S-M (∼150 nm) on the flexible substrate demonstrates excellent stability under a wide range of illumination angles from -40° to 40° and at the curvature surface from 0.05 to 0.13 mm-1. The proposed plasmonic BIC strategy is very promising for many other hot-electron-related fields, such as photocatalysis, biosensing, imaging, and so on.

Lithium Ion Intercalation-Induced Metal-Insulator Transition in Inclined-Standing Grown 2D Non-Layered Cr2S3 Nanosheets.

Gate-controlled ionic intercalation in the van der Waals gap of 2D layered materials can induce novel phases and unlock new properties. However, this strategy is often unsuitable for densely packed 2D non-layered materials. The non-layered rhombohedral Cr2S3 is an intrinsic heterodimensional superlattice with alternating layers of 2D CrS2 and 0D Cr1/3. Here an innovative chemical vapor deposition method is reported, utilizing strategically modified metal precursors to initiate entirely new seed layers, yields ultrathin inclined-standing grown 2D Cr2S3 nanosheets with edge instead of face contact with substrate surfaces, enabling rapid all-dry transfer to other substrates while ensuring high crystal quality. The unconventional ordered vacancy channels within the 0D Cr1/3 layers, as revealed by cross-sectional scanning transmission electron microscope, permitting the insertion of Li+ ions. An unprecedented metal-insulator transition, with a resistance modulation of up to six orders of magnitude at 300 K, is observed in Cr2S3-based ionic field-effect transistors. Theoretical calculations corroborate the metallization induced by Li-ion intercalation. This work sheds light on the understanding of growth mechanism, structure-property correlation and highlights the diverse potential applications of 2D non-layered Cr2S3 superlattice.

Achieving Reliable and Ultrafast Memristors via Artificial Filaments in Silk Fibroin.

The practical implementation of memristors in neuromorphic computing and biomimetic sensing suffers from unexpected temporal and spatial variations due to the stochastic formation and rupture of conductive filaments (CFs). Here, the biocompatible silk fibroin (SF) is patterned with an on-demand nanocone array by using thermal scanning probe lithography (t-SPL) to guide and confine the growth of CFs in the silver/SF/gold (Ag/SF/Au) memristor. Benefiting from the high fabrication controllability, cycle-to-cycle (temporal) standard deviation of the set voltage for the structured memristor is significantly reduced by ≈95.5% (from 1.535 to 0.0686 V) and the device-to-device (spatial) standard deviation is also reduced to 0.0648 V. Besides, the statistical relationship between the structural nanocone design and the resultant performance is confirmed, optimizing at the small operation voltage (≈0.5 V) and current (100 nA), ultrafast switching speed (sub-100 ns), large on/off ratio (104 ), and the smallest switching slope (SS < 0.01 mV dec-1 ). Finally, the short-term plasticity and leaky integrated-and-fire behavior are emulated, and a reliable thermal nociceptor system is demonstrated for practical neuromorphic applications.

Customizing 2.5D Out-of-Plane Architectures for Robust Plasmonic Bound-States-in-the-Continuum Metasurfaces.

Bound states in the continuum (BICs) have a superior ability to confine electromagnetic waves and enhance light-matter interactions. However, the quality-factor of quasi-BIC is extremely sensitive to structural perturbations, thus the BIC metasurfaces usually require a very-high precision nanofabrication technique that greatly restricts their practical applications. Here, distinctive 2.5D out-of-plane architectures based plasmonic symmetry protected (SP)-BIC metasurfaces are proposed, which could deliver robust quality factors even with large structural perturbations. The high-throughput fabrication of such SP-BIC metasurfaces is realized by using the binary-pore anodic aluminum oxide template technique. Moreover, the deep neural network (DNN) is adapted to conduct multiparameter fittings, where the 2.5D hetero-out-of-plane architectures with robust high quality-factors and figures of merit are rapidly predicted and fabricated. Finally, owning to its large second-order surface sensitivity, the desired 2.5D hetero-out-of-plane architecture demonstrates a detection limit of endotoxin as low as 0.01 EU mL-1 , showing a good perspective of biosensors and others.

Evaluating the value of anti-SARS-CoV-2 antibody detection and neutralizing responses with euvirus: A population of 10776 close contacts in the epidemic of Fujian.

BACKGROUND: Nucleic acid detection represents limitations due to its false-negative rate and technical complexity in the COVID-19 pandemic. Anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody tests are widely spread all over the world presently. However, there is no report on the effectiveness of anti-SARS-CoV-2 antibody testing methods in China. METHODS: We gathered 10776 serum samples from close contacts of the SARS-CoV-2 infections in Fujian of China and used 2 chemiluminescence immunoassays (Wantai Bio., Yahuilong Bio.) and 2 lateral flow immunoassays (Lizhu Bio. and Dongfang Bio.) to perform the anti-SARS-CoV-2 antibody tests in China. RESULTS: The 4 antibody tests have great diagnostic value for infected or uninfected, especially in the neutralizing antibodies tests, the AUC can reach 0.939 (Wantai Bio.) and 0.916 (Yahuilong Bio.). Furthermore, we used pseudoviruses and euvirus neutralization assay to validate the effectiveness of these antibody test, the results of pseudoviruses neutralization assay or euvirus neutralization assay shows a considerable correlation with the 4 antibody detection respectively, particularly in euvirus neutralization assay, neutralizing antibodies detected by Wantai Bio. or Yahuilong Bio., the correlation can get the level of 0.93 or 0.82. CONCLUSIONS: The findings of this study demonstrate that the detections of antibodies have profound value in the diagnosis of COVID-19.

Effectiveness of SARS-CoV-2-inactivated vaccine and the correlation to neutralizing antibodies: A test-negative case-control study.

Severe acute respiratory syndrome coronavirus 2 breakthrough infection in highly vaccinated populations raises study on the effectiveness for inactivated vaccine, including effectiveness of the vaccine dose, the continuance of effectiveness, the effectiveness against severe/critical coronavirus disease 2019 and against secondary attacks. A population of 10 870 close contacts were investigated in a Delta variant's epidemic. The effectiveness of vaccination was estimated in a test-negative case-control study. In addition, serum was used to detect neutralizing antibodies, to explore their correlation to effectiveness. The vaccine effectiveness (VE) values were estimated for populations aged 12 years or older. The overall adjusted VE was 56.2% and a two-dose vaccine was more effective than a one-dose vaccine (56.7% vs. 43.8%). In addition, the population that got the second dose vaccine within 2 months showed higher VE than the population vaccinated for longer than 2 months (61.5% vs. 52.3%). Among the population who vaccinated 2 doses or within 2 months, a higher level of neutralizing antibodies was observed. For infected cases, vaccinated populations showed lower rates of transmission (2.63% vs. 4.36%). Further, those vaccinated cases, who were not found causing transmission, had a higher level of antibodies. The study provided a full view of the effectiveness of inactivated vaccines in a real-world setting. The time-related VE against infection and lower transmission of breakthrough vaccinated cases were observed, which may indicate that a necessity of a booster vaccine to maintain the effectiveness and high level of neutralizing antibody.

Satisfactory Anti-Interference and High Performance of the 1Co-1Ce/Mn@ZSM-5 Catalyst for Simultaneous Removal of NO and Hg0 in Abominable Flue Gas.

The removal performance of NO and Hg0, the operating temperature window, and the resistance of SO2 and H2O on Mn@ZSM-5 catalyst, which was synthesized by a one-step hydrothermal method with manganese oxide as the active component, were improved by doping different molar ratios of Co/Ce. Co and Ce doping increased the content of Mn4+ as well as of chemisorbed oxygen and promoted the NO and Hg0 removal performance, which reached 96.7 and 98.9%, respectively, in flue gas over the 1Co-1Ce/Mn@ZSM-5 catalyst. Furthermore, with SO2 and H2O addition, it decreased slightly to 88.4 and 89.3%, respectively, and then remained stable. The coexistence of SO2 and H2O had a synergistic poisoning effect on the activity of the catalyst, while the doping of Co and Ce had a positive influence on the tolerance to SO2 and H2O. The excellent anti-interference and high performance of the 1Co-1Ce/Mn@ZSM-5 catalyst in the abominable flue gas were mainly due to the outer surface modification of organosilane and because the sacrificial element Co protected the active sites of Ce and Mn from poisoning, which prevented the redox ability of the catalyst from getting affected.

BiOCl/TiO2/diatomite composites with enhanced visible-light photocatalytic activity for the degradation of rhodamine B.

A BiOCl/TiO2/diatomite (BTD) composite was synthesized via a modified sol-gel method and precipitation/calcination method for application as a photocatalyst and shows promise for degradation of organic pollutants in wastewater upon visible-light irradiation. In the composite, diatomite was used as a carrier to support a layer of titanium dioxide (TiO2) nanoparticles and bismuth oxychloride (BiOCl) nanosheets. The results show that TiO2 nanoparticles and BiOCl nanosheets uniformly cover the surface of diatomite and bring TiO2 and BiOCl into close proximity. Rhodamine B was used as the target degradation product and visible light (λ > 400 nm) was used as the light source for the evaluation of the photocatalytic properties of the prepared BTD composite. The results show that the catalytic performance of the BTD composite under visible-light irradiation is much higher than that of TiO2 or BiOCl alone. When the molar ratio of BiOCl to TiO2 is 1:1 and the calcination temperature is 400 °C, the composite was found to exhibit the best catalytic effect. Through the study of the photocatalytic mechanism, it is shown that the strong visible-light photocatalytic activity of the BTD composite results mainly from the quick migration of photoelectrons from the conduction band of TiO2/diatomite to the surface of BiOCl, which promotes the separation effect and reduces the recombination rate of the photoelectron-hole pair. Due to the excellent catalytic performance, the BTD composite shows great potential for wide application in the field of sewage treatment driven by solar energy.

Metal organic frameworks derived cobalt sulfide/reduced graphene oxide composites with fast reaction kinetic and excellent structural stability for sodium storage.

We report a metal-organic framework-derived Co9S8 nanoflakes on reduced graphene oxide sheet composites as an advanced sodium-ion battery anode. Using a galvanostatic intermittent titration technique, we reveal that the sodium diffusion coefficient of the composite is higher than that of its counterpart. Ex-situ scanning electron microscopy images suggest the excellent mechanical stability of Co9S8 nanoflakes on the reduced graphene oxide sheet electrode during cycling, thereby facilitating cyclic stability. The partial surface-induced capacitive effect also contributes to electrochemical performance. With the reduced graphene oxide, the Co9S8 nanoflakes on the reduced graphene oxide sheet electrode deliver a high discharge capacity of 551 mA h g-1 at 0.1 A g-1, a good rate capability at 10 A g-1, and an excellent cyclic stability up to 500 cycles. rGO/Co9S8 shows potential for practical applications in Na3V2(PO4)3‖rGO/Co9S8 full cells.

Synthesis of a MnO2/Fe3O4/diatomite nanocomposite as an efficient heterogeneous Fenton-like catalyst for methylene blue degradation.

Heterogeneous Fenton-like catalysts with the activation of peroxymonosulfate (PMS), which offer the advantages of fast reaction rate, wide functional pH range and cost efficiency, have attracted great interest in wastewater treatment. In this study, a novel magnetic MnO2/Fe3O4/diatomite nanocomposite is synthesized and then used as heterogeneous Fenton-like catalyst to degrade the organic pollutant methylene blue (MB) with the activation of PMS. The characterization results show that the Fe3O4 nanoparticles and nanoflower-like MnO2 are evenly distributed layer-by-layer on the surface of diatomite, which can be readily magnetically separated from the solution. The as-prepared catalyst, compared with other Fenton-like catalysts, shows a superb MB degradation rate of nearly 100% in 45 min in the pH range of 4 to 8 and temperature range of 25 to 55 °C. Moreover, the nanocomposite shows a good mineralization rate of about 60% in 60 min and great recyclability with a recycle efficiency of 86.78% after five runs for MB. The probable mechanism of this catalytic system is also proposed as a synergistic effect between MnO2 and Fe3O4.

Fabrication of novel sandwich nanocomposite as an efficient and regenerable adsorbent for methylene blue and Pb (II) ion removal.

An adsorbent, which is easy to be separated and reused after adsorption, is very important for the removal of pollutants in aqueous solution. Hence, a novel nanofibrous sandwich structured adsorbent of silica nanofiber/magnetite nanoparticles/porous silica (SNF/MNP/PS) was designed and synthesized for the first time. The magnetite nanoparticles with diameter less than 10 nm were evenly distributed on the surface of silica nanofiber, which was subsequently fully covered by a layer of porous silica. The novel adsorbent was proved possessing good adsorption capacity for both methylene blue (MB) and Pb (II) ion (Pb2+), and the adsorption equilibrium could be well described by the Langmuir-isotherm model with the maximum adsorption capacity of 103.1 mg/g for MB and 243.9 mg/g for Pb2+ at 288 K. Moreover, in MB-Pb2+ mixed system the measured adsorption capacity reached 74.5 mg/g for MB and 202.4 mg/g for Pb2+, respectively. The saturated adsorbent could be readily magnetically separated from the solution and then efficiently regenerated by heterogeneous Fenton-like reaction (for MB) or acidic desorption process (for Pb2+), respectively. After 5 cycles of adsorption-regeneration, the adsorption capacity of the reused adsorbent still reached 81.0% (for MB) and 70.9% (for Pb2+) of the initial value. The SNF/MNP/PS behaves good adsorption properties for different types of pollutants, high magnetic recoverability and regeneration efficiency, which make it applicable to different contaminants removal.

Study on the correlation between adipocyte fatty-acid binding protein, glucolipid metabolism, and pre-eclampsia.

AIM: We aimed to explore the relation between the level of adipocyte fatty-acid binding protein (A-FABP) in the gestational period and related indices of glucolipid metabolism, and the possible mechanisms of occurrence and development of pre-eclampsia. METHODS: Seventy-six pre-eclampsia patients were enrolled and divided into the mild pre-eclampsia (n = 42) and severe pre-eclampsia (n = 34) groups. Forty-eight healthy pregnant women were selected as a control group. The indices of all participants were examined, including serum A-FABP, fasting insulin (FINS), fasting blood glucose, total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL), and homeostatic model assessment insulin resistance (HOMA-IR) index was calculated. After the delivery of the placenta, the level of A-FABP in the placenta was detected by immunochemistry. Then, the correlation between serum A-FABP and indices of glucolipid metabolism and placental A-FABP were analyzed. RESULTS: Serum A-FABP, FINS, TG, TC, HOMA-IR, and placental A-FABP were significantly higher in pre-eclampsia patients and the level of HDL was obviously lower than in the control group. Serum A-FABP was positively correlated with FINS, TG, TC, and HOMA-IR, and placental A-FABP was negatively correlated with HDL in pre-eclampsia patients. In the control group, serum A-FABP was positively correlated only with TG, and uncorrelated with the other indices (P > 0.05). CONCLUSION: The level of A-FABP was correlated with insulin resistance and indices of glucolipid metabolism in pre-eclampsia patients. High-levels of A-FABP might increase insulin resistance by causing glucose and lipid metabolism disorders and ultimately inducing the occurrence and development of pre-eclampsia.

Carbon sphere@Co9S8 yolk-shell structure with good morphology stability for improved lithium storage performance.

The poor electronic conductivity and huge volume expansion of cobalt sulfides upon cycling would lead to their poor electrochemical performances for Lithium-ion batteries. Here, we rationally design a yolk-shell carbon sphere@Co9S8 (C@CS) composite, which demonstrates improved kinetics and excellent morphology stability during cycling. This structure can keep Co9S8 shell from collapse and aggregation. After cycling, a layer of thin solid electrolyte interphase is coated on the Co9S8 shells and prevented them from dissolving in electrolyte, which is helpful for the electrochemical performances. As a result, the C@CS electrodes exhibit good lithium storage performances, including excellent cyclic stability up to 300 cycles at 1000 and 2000 mA g-1 and high-rate property of 4000 mA g-1 with a capacity of 489 mA h g-1.

Highly efficient fluoride adsorption from aqueous solution by nepheline prepared from kaolinite through alkali-hydrothermal process.

A direct alkali-hydrothermal induced transformation process was adopted to prepare nepheline from raw kaolinite (shortened form RK in this paper) and NaOH solution in this paper. Structure and morphology characterizations of the synthetic product showed that the nepheline possessed high degree of crystallinity and uniform surface morphology. Specific surface area of nepheline is 18 m2/g, with a point of zero charge at around pH 5.0-5.5. The fluoride (F- ions) adsorption by the synthetic nepheline (shortened form SN in this paper) from aqueous solution was also investigated under different experimental conditions. The adsorption process well matched the Langmuir isotherm model with an amazing maximum adsorption capacity of 183 mg/g at 323 K. The thermodynamic parameters (ΔG0, ΔH0, and ΔS0) for adsorption on SN were also determined from the temperature dependence. The adsorption capacities of fluoride on SN increased with increasing of temperature and initial concentration. Initial pH value also had influence on adsorption process. Adsorption of fluoride was rapidly increased in 5-60 min and thereafter increased slowly to reach the equilibrium in about 90-180 min under all conditions. The adsorption followed a pseudo-second order rate law.