Latest ArticlesOrganic pollutants are harmful and toxic chemical substances that adversely threaten human health and the living environment all over the world. More and more studies have been investigating the relationship between low level of human exposure of organic compounds and various internal diseases. For the sake of assessing disease risk due to organic compounds contact in a particular location, it is imperative for relevant government departments to make a human health risk assessment in view of the organic pollutants’ bioavailability and their dosage-response correlations. It is inevitable to make use of an efficient method to detect organic pollutants, which is significant for public health and safety. Fluorescent assays based on carbon dots thus would provide a very plausible candidate method. After consulting a large number of literatures, we offer a comprehensive review of the sensing applications of carbon dots for organic pollutants.
In our work, polymorphism strategy has been successfully applied to tune up chromism and luminescence properties of viologen-based materials. Two polymorphs of viologen-based complexes of α-CdBr2(PHSQ)2(H2O)2 (1) and β-CdBr2(PHSQ)2(H2O)2 (2) (PHSQ = N-(4-sulfophenyl)-4,4′-bipyridinium) were synthesized by changing the solvent. They can both respond to UV light and electricity in the manner of chromism visible to the naked eye and the coloration states have good reversibility, through which an inkless erasable printing model has been established. But the coloration contrast of 1 is higher compared to 2. Meanwhile, they both exhibit photoluminescence properties and the intensity of 1 is twice that of 2, which is accompanied by photoquenching upon continuous UV light irradiation. The only divergence of disordered/ordered O atoms in the two crystalline compounds leads to significantly different chromic and luminescent properties. Further explorations simultaneously demonstrate that the different chromic performance between 1 and 2 should attribute to the alteration of stimulus-induced (light/ electricity) electron transfer channels caused by the ordered/disordered O atoms in the complexes, which is achieved through CH···O and OH···O interactions to change crystal arrangement and structural rigidity, thus affect luminescent properties.
Photocatalysis is widely regarded as a highly promising sustainable technique for addressing the challenges posed by environmental pollution and energy provision. In recent years, metal-loaded MOFs has become a rising star within the domain of photocatalysis due to its high specific surface area and porosity, adjustable structure, diverse and abundant catalytic components, which has exhibited excellent photocatalytic activity and exhibit great potential in a range of disciplines. In this paper, the principles for evaluating the photocatalytic performance of MOFs-based materials were firstly introduced, and some typical examples were also listed accordingly. Along with this, particular emphasis is paid to the main factors affecting the photocatalytic performance of metal-loaded MOFs. Then the synthesis and design strategies of MOFs loaded metal entities of varying sizes (single atoms, nanoclusters, and nanoparticles), and their applications in photocatalytic CO2 reduction, hydrogen production, photooxidation and photocatalytic hydrogenation were summarized and discussed. Finally, the opportunities and challenges faced in this kind of MOFs-based composites were analyzed from different perspectives. This report is expected to help researchers design and develop high-performance MOFs-based photocatalytic materials.
Quantitative determination of tetracycline (TC) in environment and foods is of great importance, as excessive residues might have negative effects on human health and environmental risks. Herein, a self-powered molecularly imprinted photoelectrochemical (PEC) sensor based on the ZnO/C photoanode and the Fe-doped CuBi2O4 (CBFO) photocathode is developed for the sensitive detection of TC. The photocathodic current can be amplified by the efficient electron transfer caused by the Fermi energy level gap between the photoanode and photocathode. Furthermore, molecularly imprinted polymers (MIPs) at photocathode can selectivity identify the TC templates and thus improve the specificity. Under the optimal conditions, the sensor has a linear range of 10‒2–1.0 × 105 nmol/L, and a limit of detection (LOD) of 0.007 nmol/L (S/N = 3). More crucially, the milk sample detection is carried out using the as-prepared sensor, and the outcome is satisfactory. The research gives us a novel sensing platform for quick and accurate antibiotic (like TC) in environment and food monitoring.
Diradicaloid polycyclic hydrocarbons (PHs) own unique open-shell electronic structures and exhibit potential utility in the fields of organic electronics and spintronics. Herein, we disclose precise fusion of B/O-heterocycles onto PHs for control over their electronic structures and diradical properties. We designed and synthesized four B/O-containing diradicaloid isomers that feature the fluoreno[3,2-b]fluorene and fluoreno[2,1-a]fluorene π-skeletons, respectively. The precise B/O-heterocycle fusion modes along with the changed conjugation patterns lead to their modulated electronic structures and properties, such as diradical and aromatic structures, energy levels and band gaps, as well as magnetic, electrochemical and photophysical properties. Notably, the mode A may decrease the open-shell extent, whereas the mode B can enhance the diradical nature, leading to their well-tuned diradical characters in the range of 0.46‒0.70. Moreover, the mode A stabilizes the LUMOs and the mode B obviously increases the HOMO levels, which are remarkably contributed by the B and O atoms, respectively, further giving rise to the decreased band gaps and redshifted absorptions. This study clearly illustrates the electronic effects of B/O-heterocycle fusion on PHs and gains insight into B/O-type organic diradicaloids. These findings will provide an important guideline for the design of more fascinating heteroatom-containing diradicaloids.
Copper (Cu) is widely used in the electrochemical carbon dioxide reduction reaction (ECO2RR) for efficient methane (CH4) product. However, the morphology and valence of Cu-based catalysts are usually unstable under reaction conditions. In this work, we prepared Ce-doped MOF-199 precursor (Ce/HKUST-1) and further obtained nanoparticle electrocatalyst Ce/CuOx-NPs by cyclic voltammetry (CV) pretreatment. The Faradic efficiency of methane () maintains above 62% within a broad potential window of 350 mV and the maximum reaches 67.4% with a partial current density of 293 mA/cm2 at −1.6 V vs. a reversible hydrogen electrode. Catalyst characterization and theoretical calculations revealed that the unique electronic structure and large ionic radius of Cerium (Ce) not only promoted the generation of key intermediate *CO but also lowered energy barrier of the *CO to *CHO step. This study provides a novel and efficient catalyst for methane production in ECO2RR and offers profound insights into constructing high performance Cu-based catalysts.
Membrane electrode assembly (MEA) is widely considered to be the most promising type of electrolyzer for the practical application of electrochemical CO2 reduction reaction (CO2RR). In MEAs, a square-shaped cross-section in the flow channel is normally adopted, the configuration optimization of which could potentially enhance the performance of the electrolyzer. This paper describes the numerical simulation study on the impact of the flow-channel cross-section shapes in the MEA electrolyzer for CO2RR. The results show that wide flow channels with low heights are beneficial to the CO2RR by providing a uniform flow field of CO2, especially at high current densities. Moreover, the larger the electrolyzer, the more significant the effect is. This study provides a theoretical basis for the design of high-performance MEA electrolyzers for CO2RR.
Highly toxic phosgene, diethyl chlorophosphate (DCP) and volatile acyl chlorides endanger our life and public security. To achieve facile sensing and discrimination of multiple target analytes, herein, we presented a single fluorescent probe (BDP-CHD) for high-throughput screening of phosgene, DCP and volatile acyl chlorides. The probe underwent a covalent cascade reaction with phosgene to form boron dipyrromethene (BODIPY) with bright green fluorescence. By contrast, DCP, diphosgene and acyl chlorides can covalently assembled with the probe, giving rise to strong blue fluorescence. The probe has demonstrated high-throughput detection capability, high sensitivity, fast response (within 3 s) and parts per trillion (ppt) level detection limit. Furthermore, a portable platform based on BDP-CHD was constructed, which has achieved high-throughput discrimination of 16 analytes through linear discriminant analysis (LDA). Moreover, a smartphone adaptable RGB recognition pattern was established for the quantitative detection of multi-analytes. Therefore, this portable fluorescence sensing platform can serve as a versatile tool for rapid and high-throughput detection of toxic phosgene, DCP and volatile acyl chlorides. The proposed "one for more" strategy simplifies multi-target discrimination procedures and holds great promise for various sensing applications.
The dysbiosis of oral microbiota contributes to diseases such as periodontitis and certain cancers by triggering the host inflammatory response. Developing methods for the immediate and sensitive identification of oral microorganism is crucial for the rapid diagnosis and early interventions of associated diseases. Traditional methods for microbial detection primarily include the plate culturing, polymerase chain reaction and enzyme-linked immunosorbent assay, which are either time-consuming or laborious. Herein, we reported a persistent luminescence-encoded multiple-channel optical sensing array and achieved the rapid and accurate identification of oral-derived microorganisms. Our results demonstrate that electrostatic attractions and hydrophobic-hydrophobic interactions dominate the binding of the persistent luminescent nanoprobes to oral microorganisms and the microbial identification process can be finished within 30 min. Specifically, a total of 7 oral-derived microorganisms demonstrate their own response patterns and were differentiated by linear discriminant analysis (LDA) with the accuracy up to 100% both in the solution and artificial saliva samples. Moreover, the persistent luminescence encoded array sensor could also discern the microorganism mixtures with the accuracy up to 100%. The proposed persistent luminescence encoding sensor arrays in this work might offer new ideas for rapid and accurate oral-derived microorganism detection, and provide new ways for disease diagnosis associated with microbial metabolism.
Rational design of viable routes to obtain efficient and stable oxygen evolution reaction (OER) electrocatalysts remains challenging, especially under industrial conditions. Here, we provide a solvent-steam assisted corrosion engineering strategy to directly fabricate high-entropy NiFe-LDH with spatially resolved structural order. Ammonium fluoride in methanol steam enables the formation of nanosheets while Fe3+ effectively enhances their adhesion to the semi-sacrificial nickel-iron foam (NFF), thereby conjuring up a NiFe-LDH@NFF catalyst that exhibits remarkable adaptability to robust electrochemical activation yet with excellent stability. Comprehensive measurements reveal the in-situ formation of high-valance metal oxyhydroxide and the enhancement of adsorption-desorption process. Under the industrial condition (6 mol/L KOH, 60 ℃), the NiFe-LDH@NFF exhibits excellent activity of 50 mA/cm2 at 1.55 V and high durability of over 120 h at 200 mA/cm2. We anticipate that the steam assisted strategy could promote the development of efficient non-precious electrocatalysts for hydrogen energy.
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62662699(Operation and Technical Support)
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
