Journal of The Chinese Chemical Society最新文献

Using cobalt sulfate and nickel sulfate as main electrolytes, ammonium sulfate as an auxiliary electrolyte and buffer agent, and cheap iron pieces (FP) as the substrates, nickel and/or cobalt phosphide/metal heterogeneous catalytic electrode (M₂P/M/FP) was grown on the substrate in situ by electrodeposition followed by low temperature phosphating. M₂P/M/FP functioned as a good bifunctional electrode for HER and OER in 1 mol/L KOH, where Co₂P/Co/FP needed an overpotential of 52 and 288 mV, and (NC)₂P/(NC)/FP required that of 75 mV and 293 mV to afford 10 mA/cm². Previous similar studies often ignored the role of metal and only considered the water electrolysis catalysis of metal phosphide. In this research, it was clarified that for water electrolysis, the essence of high catalysis activity of the M₂P/M/FP electrode was the electronic interaction between metal and metal phosphide.

Reasonable design is of great significance for improving the performance of electrochemiluminescence (ECL) co-reactant accelerators. The different d-band structure of metal single atoms will produce different oxidation states, which may change the adsorption of reaction intermediates to the catalyst and affect its catalytic activity. In this study, we have demonstrated that the ECL performances of graphite carbon nitride (CN) can be promoted by modulating the metal oxidation states of co-reaction accelerator for the first time. The oxidation states of Au were modulated by the different electronic metal–support interaction (EMSI) between the co-reaction accelerator (Au single atoms, Au nanoparticles [Au NPs]) and CN, and the effects of Au oxidation states on the ECL performances of CN were investigated. Comparison to pristine CN and CN nanosheets supported Au nanoparticles (Au NPs/CN), stronger and more stable ECL intensity of CN nanosheets supported Au single-atoms (Au^S/CN) was obtained. The ECL signal of Au^S/CN was about 32.2 times that of the original CN, and 2.8 times that of Au NPs/CN in the same Au loading content (0.8%). Detailed mechanism revealed that Au^S/CN with higher Au oxidation state has better conductivity and stronger catalytic activity, which promotes the electric reduction of CN and S₂O₈²⁻, increases the lifetime of the excited state CN*, and significantly improves the ECL performance of CN. In addition, this work provides a detailed understanding of the essence of EMSI for the ECL intensity amplification and established a feasible method for the improvement of ECL capacities of co-reactant accelerators.

In this paper, the design concept aims to convey the overall background of the published literature, emphasizing the concept of food safety. It utilizes a magnifying glass to symbolize the analysis of various parts of preserved eggs described in the text. Additionally, the spectrogram concept in the bottom right corner highlights the detection methods. More details about this figure will be discussed by Dr. Tsung-Ting Shih and his co-workers on page 474–481 in this issue.

Parabens are frequently used preservatives in food and personal care products. These are also termed endocrine disruptors which have the potential to damage the endocrine system Therefore, an easy and facile extraction and detection of parabens are critically important. This work evaluates different magnetic sorbents such as Fe₃O₄@MIL-101(Cr), Fe₃O₄@MIL-101(Cr)@NH₂, and Fe₃O₄@MIL-101(Cr)@SO₃H for magnetic solid phase extraction (MSPE) and further selected Fe₃O₄@MIL-101(Cr)@NH₂ to determine paraben content in chili powder and facial toner samples. Fe₃O₄@MIL-101(Cr)@NH₂ is an efficient sorbent material specially designed for MSPE, which profoundly extracted nine parabens within a short span of just 6 min, driven by π–π interaction and hydrogen bonding. And a detailed optimization and LC–MS/MS analysis was carried out. Fe₃O₄@MIL-101(Cr)@NH₂ exhibited superior extraction efficiency, enabling subsequent quantification via LC–MS/MS. The limit of detection ranged from 0.063 to 0.622 ng mL⁻¹ and limit of quantification of 0.211 to 2.073 ng mL⁻¹ were a good recovery in the range of 76.2%–108%. An effective detection of eight parabens in chili powder and four parabens in facial toner samples was determined indicating that Fe₃O₄@MIL-101(Cr)-NH₂ sorbents are suitable for MSPE.

The important role to neuron communication and brain functions makes the selective and accurate detection of dopamine (DA, a typical neurotransmitter) significant. In this study, a morin-based probe has been reported for the ratiometric DA detection. The mechanism study discloses that the inside resorcinol motif can specifically react with DA and form fluorescent azamonardine-like product. In addition, the intrinsic emission from the internal chromophore endows ratiometric variation. With these features, selective DA sensing is realized using morin probe with a limit of detection of 2.2 nM (S/N = 3). Moreover, the practical application of the proposed method is further validated by the accurate DA determination in urine samples. This work demonstrates the possible exploration of novel small molecule-based ratiometric-sensing systems toward various analytes with the combination of proper reaction motif and chromophore. It is expected that the development of versatile probes for the ratiometric and accurate recognition of environmental and biological markers can refer such a design strategy.

Perovskite materials with unique crystal structure have developed rapidly in recent years owing to their special physical and chemical properties, such as high light absorption and extraordinary electrocatalytic properties. Metal halide perovskites are quite attractive in various fields because of their simple manufacturing process, adjustable band gap, good charge transfer performance, and high theoretical photoelectric conversion efficiency. Therefore, perovskite oxides mixed with metal elements become ideal samples for studying the surface and catalytic performance of catalysts. In this review, various metal perovskites are clearly classified and introduced according to the corresponding synthesis methods, including hydrothermal method, sol–gel method, and high-temperature solid phase, as well as coprecipitation. The excellent properties of perovskite make it extensively used in nanotechnology, chemistry, environmental protection, and material science, especially in solar cells and sensors. In particular, the nanosized perovskite materials are becoming more and more popular in sensors, which was reviewed in detail here. Most importantly, the design of electrochemical sensors using perovskite nanomaterials with low detection limit and high sensitivity will bring new insight into the detection of biomolecules. Both challenges and prospects of metal perovskites were discussed for promoting the development of biosensors in the end.

This study synthesized a nanocomposite based on quaternary branched polyethyleneimine containing sodium alginate and graphene oxide and characterized by FE-SEM, EDX-MAP, XRD, FT-IR, and TGA and used as an efficient sorbent for the removal of nitrate ions. The maximum ion exchange in optimized conditions was discovered to be 75%. The experimental studies showed that nitrate removal follows the pseudo-first-order model due to more consonance. Also, Weber–Morris and Boyd models suggested that the nitrate ions adsorption on the surface of nanocomposite is not controlled only by the intraparticle diffusion step. Moreover, Langmuir, Redlich–Peterson, and Hill models exhibited high regression coefficients of 0.991, 0.993, and 0.992, respectively. Thermodynamic studies confirmed the adsorption system was spontaneous and exothermic. Recovery assay showed that more than 98% of the nitrate ion exchanged by the nanocomposite was regenerated and nanocomposite could be reused seven cycles without efficacy reducing significantly. The nanocomposite showed excellent antibacterial activity against Staphylococcus aureus and Escherichia coli cells, with minimum inhibitory concentrations of 62.5 and 125 μg mL⁻¹, and zone of growth inhibition of 17.5 ± 0.5 and 10.5 ± 0.5 mm, respectively. The results represented that the introduced nanocomposite is a useful material for the removal of nitrate ions from aqueous solution and has antibacterial properties.