Latest ArticlesIn-situ monitoring of pesticide residues during crop growth or/and in related products is of great significance in avoiding the abuse of pesticides but remains challenging thus far. In this report, we proposed a background-free surface-enhanced Raman spectroscopy (bf-SERS) platform to non-destructively track the nitrile-bearing pesticide residues in soybean leaves with high sensitivity and selectivity. The outstanding feature of the assay stems from the dramatic Raman enhancement effect of the 50 nm-sized gold nanoparticles (AuNPs) towards the pesticides and simultaneously the background-free Raman signal of the nitrile group in the so-called Raman-silent region (1800–2800 cm‒1). This bf-SERS assay was applied to evaluate the penetration effects of nitrile-bearing pesticides and monitor their residues in soybean leaves after rinsing with various solutions, providing a reliable tool for guiding the safe use of nitrile-bearing pesticides in agriculture.
Mineralization of the ZIF-8 in the presence of biomacromolecules has been demonstrated to be a general way for making bioentities@ZIFs composites. The ZIF-8 crystals permit controlled storage and utilization of the bioentities, thus can benefit drug delivery, cold-chain breaking etc. With the increasing needs on personal care and distributed manufacturing, automated synthesis controlled by a computer becomes the next challenge. In this work, we designed an automatic synthesis system to prepare PEG mineralized ZIF-8 composite particles. This system is based on flow chemistry with the microfluidic chips fabricated by femtosecond laser micromachining. The particles were synthesized and monitored automatically. Furthermore, this synthesizer could be extended for fabrication of vaccine particles under remote control through internet.
Hierarchical superstructures assembled by nanosheets can effectively prevent aggregation of nanosheets and improve performance in energy storage. Therefore, we proposed a facile hydrothermal method to obtain three-dimensional (3D) superstructure assembled by nanosheets. We found that the ratio of Co2+/HMTA affected the morphology of the samples, and the 3D hierarchical structures of are obtained while the ratio of Co2+/HMTA is 12:25. The hierarchical structures with sufficient interior space preserves the original sheet-like dimensional components and results in sufficient active sites and efficient mass diffusion. Hence, the 3D Co2V2O7·nH2O hierarchical structure exhibits good rate capability and high stability while as electrode materials. Meanwhile, when power density is 745.13 W/kg, the assembled CVO-2//AC shows an energy density of 47.7 Wh/kg. The work displays a facile method for fabrication of 3D superstructure assembled by 2D nanosheets that can be applied in energy storage.
A great concern has been raised regarding the issue of fluoroquinolones (FQs) in the environment. In this work, the transformation of FQs by commonly used oxidant permanganate (Mn(Ⅶ)) in the absence and presence of humic acid (HA), ubiquitously existing in aquatic environments, was systematically investigated. Here, the catalytic role of in-situ formed MnO2 on Mn(Ⅶ) oxidation of FQs depending on solution pH and co-existing substrates was firstly reported. It was interestingly found that HA could appreciably accelerate FQs degradation by Mn(Ⅶ) at environmentally relevant pH. HA as a reductant in accelerating FQs by Mn(Ⅶ) oxidation was distinctly elucidated for the first time, where MnO2 in situ formed from the reduction of Mn(Ⅶ) by HA served as a catalyst. Similar products were observed in the presence versus absence of HA. Considering that the accelerating role of HA was related to its reducing ability, an activation method based on Mn(Ⅶ) and reductant (i.e., Fe(Ⅱ), Mn(Ⅱ) and (bi)sulfite) was proposed, which exhibited considerable potential for application in the treatment of FQs contaminated water.
With the in-depth research of sodium-ion batteries (SIBs), the development of novel sodium-ion anode material has become a top priority. In this work, tube cluster-shaped SbPS4 was synthesized by a high-temperature solid phase reaction. Then the typical short tubular ternary thiophosphate SbPS4 compounded with graphene oxide (SbPS4/GO) was successfully synthesized after ultrasonication and freeze-drying. SbPS4 shows a high theoretical specific capacity (1335 mAh/g) according to the conversion-alloying dual mechanisms. The unique short tube inserted in the spongy graphene structure of SbPS4/GO results in boosting the Na ions transport and alleviating the huge volume change in the charging and discharging processes, improving the sodium storage performance. Consequently, the tubular SbPS4 compounded with 10% GO provides an outstanding capacity of 359.58 mAh/g at 500 mA/g. The result indicates that SbPS4/GO anode has a promising application potential for SIBs.
How to utilize inexhaustible solar light as a means of disinfection technology for its cheap and green remains a challenge. In this work, core-shell ZnO@ZIF-8 was synthesized and used for bacterial inactivation synergizing with peroxymonosulfate (PMS) under visible light irradiation. It took 50 min to achieve thorough sterilization for 7.5-log Escherichia coli (E. coli) cells in vis/PMS/ZnO@ZIF-8 system, compared with that 4.5-log reduction completed in vis/PMS/ZnO system under the same conditions. The enhanced photocatalytic disinfection mechanisms of fabricated ZnO@ZIF-8 were investigated by UV–vis diffuse reflectance spectra, electrochemical impedance spectra and Mott-Schottky plots. The promoted bactericidal efficiency was attributed to higher charge-separation efficiency and stronger oxidation ability of photo-generated holes. Moreover, it was found that 1O2 and •OH induced bacterial cell lesion process, and the former was the main active species. The external reactive oxygen species (ROS) caused a series of cell wall damage, intercellular ROS up-regulation and genome DNA unwinding, finally resulted in irreversible bacterial death. A two-route mechanism in vis/PMS/ZnO@ZIF-8 system was proposed, in which the generation of 1O2 was supposed as the product of the oxygen oxidation of photo-generated holes and PMS dissociation. Our work is expected to provide advanced information about a low-cost water disinfection technology of visible light photocatalysis.
The electroreduction of CO2 (CO2RR) into value-added chemicals is a sustainable strategy for mitigating global warming and managing the global carbon balance. However, developing an efficient and selective catalyst is still the central challenge. Here, we developed a simple two-step pyrolysis method to confine low-valent Ni-based nanoparticles within nitrogen-doped carbon (Ni-NC). As a result, such Ni-based nanoparticles can effectively reduce CO2 to CO, with a maximum CO Faradaic efficiency (FE) of 98% at an overpotential of 0.8 V, as long as good stability. Experimental and the density functional theory (DFT) calculation results reveal that low-valent Ni plays a key role in activity and selectivity enhancement. This study presents a new understanding of Ni-based CO2RR, and provides a simple, scalable approach to the synthesis of low-valent catalysts towards efficient CO2RR.
As an essential part in the toolbox of super-resolution microscopy, stimulated emission depletion (STED) nanoscopy has been widely explored in revealing the substructure and bioactivities in fluorescence imaging. Among the applied STED fluorophores, silicon-substituted rhodamines (SiRs) belong to one of the most extensively employed fluorophores. The carboxy-SiR was favored in STED bioimaging with many advantages, including reliable photostability, cell permeability, tunable fluorogenicity, feasible structural decoration and so on. We reviewed the research of carboxy-SiR in the STED nanoscopy and hopefully this can inspire more efforts in the design and application of STED fluorophores.
The synthesis, structure, and properties of pyrene-based conformationally adaptive macrocycles are described. This new type of conformationally adaptive macrocycle was constructed through Perkin reaction, followed by imidization. By changing the condensation partner as the linking unit, a family of conjugated macrocycles with different sizes of the cavity was synthesized, which provide a simple and modular synthetic strategy towards the conformationally adaptive macrocycles. Furthermore, the macrocycles provide two well-defined conformations through flipping pyrene subunit, which were unambiguously determined by single-crystal X-ray diffraction analysis. The conformational interconversion barrier was determined by density functional theory (DFT) calculations. This new macrocycle also demonstrated unique properties, such as vapochromic behavior and aggregation emission enhancement effect. Furthermore, we have also investigated the effect of the linker on the shape and photophysical properties of the resulting macrocyclic products.
We have developed a metal-free radical cascade reaction of N-substituted 2-aryl indoles with readily available sulfonyl hydrazides for the rapid construction of arylsulfonyl-substituted indolo[2,1-a]isoquinolin-6(5H)-one derivatives. With the TBAI–TBHP catalytic system, a broad series of structurally diverse indolo[2,1-a]isoquinolin-6(5H)-one derivatives were obtained in moderate to excellent yields. The reaction features mild reaction conditions, operationally easiness, scaled-up feasibility, and high functional-group-tolerance.
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62199257
qkjq@cast.org.cn
Copyright © 2025 China Association for Science and Technology. All rights reserved. For all open access content, the relevant licensing terms apply.
Sponsored by the Office of the Leading Group for Cybersecurity and Informatization of CAST, and supported by Science and Technology Review Publishing House
