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The surface characteristics of stimuli-responsive Pickering emulsifiers can be modified by external environmental triggers, making them highly versatile in various applications. In this study, we report three novel organic–inorganic composite structure emulsifiers. These emulsifiers were designed with a core of magnetic Fe3O4 particles, surrounded by a protective silica layer, and coated on the exterior with three distinct types of modified chitosan (CS). Experimental results demonstrate that these emulsifiers can stabilize emulsion systems consisting of liquid paraffin and deionized water at a concentration of 0.5 wt%. The unique properties of the modified CS coatings allowed for the controlled demulsification of two types of emulsions by adjusting the proton concentration. Additionally, these emulsifiers exhibited magnetic-responsive demulsification under the control of an external magnetic field. The findings of this study provide valuable insights into the design and construction of multi-responsive chitosan-based magnetic Pickering emulsifiers with controllable properties. [ABSTRACT FROM AUTHOR]

Na3(VOPO4)2F (NVOPF) is an ideal cathode for high-energy-density sodium ion batteries (SIBs), due to its impressive output voltage and stable structure. However, the high production costs and complex operation processes associated with conventional synthetic methods impede its commercial applications. Herein, a simple but efficient method for large-scale low-cost synthesis of NVOPF at low temperatures is proposed. The optimal sample obtained at a suitable pH delivers a high discharge capacity of 119.6 mA h g−1 at 0.2C and remarkable cycling performance with a decay rate of merely 0.0043% per cycle over 1400 cycles at 1C. Coin-type full cells composed of NVOPF and commercial hard carbon achieve a distinguished energy density of 426.2 W h kg−1 calculated based on the cathode material. Most importantly, 2.1 A h soft-pack batteries with 100 mm in length and 60 mm in width were assembled based on the as-synthesized kilogram-scale NVOPF, which can stably cycle at 1C for 400 cycles with a capacity retention of 93.2% and an average coulombic efficiency of 99.96%. Moreover, the soft-pack battery exhibits fascinating performance in a wide temperature range, including superior rate capability at −20 °C (86.4% at 5C compared to 1C) as well as stable cycling performance at 50 °C (72.5% capacity retention after 400 cycles at 1C). This paper proposes a low-temperature co-precipitation method for synthesizing NVOPF, which significantly reduces the cost of production and contributes a solution for the industrial-scale production of NVOPF. [ABSTRACT FROM AUTHOR]

Dimethyldichlorosilane, which is the most important organic silicon monomer, can be prepared using a novel core–shell catalyst. However, the debate continues regarding its redistribution mechanism. In the current study, the redistribution mechanism catalyzed by the ZSM-5(5T)@MIL-53(Al) catalyst was theoretically studied via density functional theory on the level of M06-2X/def2-TZVP. Then, the catalytic performances of different active centers modified with AlCl3 were evaluated. The results showed that the active center of the former was Brønsted acid, while that of the latter modified by AlCl3 was Lewis acid. In addition, Lewis acid increased the catalytic activity in comparison with Brønsted acid. The calculations of activation energy, frequency vibrational analysis, bond order analysis, frontier molecular orbital theory, electronic localization function, and localized orbital locator analyses were in agreement with the said mechanism and results. [ABSTRACT FROM AUTHOR]

Herein we report a [Cp*RhCl2]2-catalyzed coupling cyclization of two different classes of allenes with 2,3-allenoic acids affording 2(5H)-furanone skeletons of products and 2,3-allenols forming a conjugated (E)-enal or enone functionality to the β-position of the 2(5H)-furanones. These products are important building blocks for the syntheses of potentially bioactive compounds. The reaction proceeded via the nucleometalation, insertion, and stereodefined 1,4-H delivery carried by rhodium. [ABSTRACT FROM AUTHOR]

A copper-catalyzed 1,4-addition reaction of sulfonyl iodides with 1,3-enynes affording various allenyl halides in high yields under mild conditions has been developed. Mechanistic studies showed that the reaction proceeds through a radical mechanism. [ABSTRACT FROM AUTHOR]

H2S is considered to be an important reductant in abiotic CO2 reduction to organics, however, almost no experimental support has been reported. Herein, the first observation of CO2 reduction to formate with H2S under alkaline hydrothermal conditions is reported, and water is found to act as a hydrogen donor. [ABSTRACT FROM AUTHOR]

Exploring novel synthesis strategies for magnetic beads to extract nucleic acids is of great significance in the field of in vitro diagnostics. In the present research, monodisperse magnetic mesoporous silica beads were synthesized via the thermolysis reaction of Fe(acac) 3 by using large-pore dendritic silica colloids as templates, and were further functionalized with a highly pH-sensitive histidine-glutamate co-oligopeptide for deoxyribonucleic acid extraction. The large-pore dendritic silica colloid scaffolds were utilized for high-density incorporation of superparamagnetic iron oxide nanoparticles within the vertical channels. The morphology and properties of the as-prepared pH-sensitive oligopeptide magnetic mesoporous silica beads were evaluated by transmission electron microscopy, scanning electron microscopy, vibrating sample magnetometry, X-ray photoelectron spectroscopy, X-ray diffraction testing and so on. The average size of the obtained magnetic beads was 370 nm in diameter with a narrow size distribution. The saturation magnetization and magnetic content of the resultant magnetic beads were 25 emu g -1 and 59%, respectively. Moreover, the magnetic mesoporous silica beads exhibited an obvious pH-responsive behavior. Due to these remarkable features, successful deoxyribonucleic acid capture using the as-prepared pH-sensitive oligopeptide magnetic mesoporous silica beads was achieved., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The surface characteristics of stimuli-responsive Pickering emulsifiers can be modified by external environmental triggers, making them highly versatile in various applications. In this study, we report three novel organic-inorganic composite structure emulsifiers. These emulsifiers were designed with a core of magnetic Fe 3 O 4 particles, surrounded by a protective silica layer, and coated on the exterior with three distinct types of modified chitosan (CS). Experimental results demonstrate that these emulsifiers can stabilize emulsion systems consisting of liquid paraffin and deionized water at a concentration of 0.5 wt%. The unique properties of the modified CS coatings allowed for the controlled demulsification of two types of emulsions by adjusting the proton concentration. Additionally, these emulsifiers exhibited magnetic-responsive demulsification under the control of an external magnetic field. The findings of this study provide valuable insights into the design and construction of multi-responsive chitosan-based magnetic Pickering emulsifiers with controllable properties.