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Aerobic oxidative desulfurization (AODS) promises a sustainable alternative desulfurization process for fuel, yet is still limited by high temperature and low efficiency for oxygen activation. Here we report that the monolayer two-dimensional vanadium carbide (V2CTx) MXene can emerge as a robust and stable catalyst for the oxidation of thiophenic compounds with oxygen in air as an oxidant. The catalyst performs a higher mass specific activity over the state-of-art vanadium oxides, activates the reaction at 70 °C, and achieves effective conversion of various sulfides under mild condition. Coupling characterizations with DFT calculations, we reveal that the abundant low valence V species accompanied anion vacancies on the surface of MXene have excellent oxygen activation capacity, which well explains its outstanding catalytic performance at low temperature. Moreover, the catalyst maintains its activity after 6 cycles of reuse, and is expected to act as a sustainable, efficient and stable AODS catalyst. [ABSTRACT FROM AUTHOR]

Aerobic oxidative desulfurization (AODS) promises to be a sustainable alternative technology for diesel desulfurization, which necessitates the efficient aerobic oxidation of thiophenic sulfides at mild conditions. Here we synthesize cerium phosphate (CePO4) nanowire-supported vanadium oxide (VOx) nanoclusters, controllably creating coordination-unsaturated V sites for boosting the AODS reaction. We propose that the electron transfer from a Ce species to a V site gives rise to the donor state and enhances its electron-donating capability for the activation of O2. We show that the catalyst possesses a higher specific activity than state-of-the-art vanadium oxide catalysts, activates reaction at 90 °C (5.17 mmol g–1 h–1), and achieves rapid conversion of various thiophenes under mild conditions. The catalyst demonstrates excellent durability in six cycles of reuse by maintaining an unchanged catalytic performance, a chemical structure, and a physical structure and is expected to act as a sustainable, efficient, and stable AODS catalyst. [ABSTRACT FROM AUTHOR]

Novel zinc–palladium–porphyrin bimetal metal–organic framework (MOF) nanosheets were directly synthesized by coordination chelation between Zn(II) and Pd(II) tetra(4-carboxyphenyl)porphin (TCPP(Pd)) using a solvothermal method. Furthermore, a serial of carbon nanosheets supported Pd–Zn intermetallics (Pd–Zn-ins/CNS) with different Pd: Zn atomic ratios were obtained by one-step carbonization under different temperature using the prepared Zn-TCPP(Pd) MOF nanosheets as precursor. In the carbonization process, Pd–Zn-ins went through the transformation from PdZn (650 °C) to Pd3.9Zn6.1 (~950 °C) then to Pd3.9Zn6.1/Pd (1000 °C) with the temperature increasing. The synthesized Pd–Zn-ins/CNS were further employed as catalysts for selective hydrogenation of acetylene. Pd3.9Zn6.1 showed the best catalytic performance compared with other Pd–Zn intermetallic forms. [ABSTRACT FROM AUTHOR]

A one-pot and green synthesis methodology was successfully designed to prepare nitrogen-doped carbon (NC) cohered Fe3O4 nanoparticles with rich oxygen vacancies (Fe3O4-OVs/NC). The preparation was achieved via cold-atmospheric-pressure air plasma using Fe2O3 nanoparticles as the only precursor, and pyridine as the carbon and nitrogen source. Systematic characterization results of the as-prepared Fe3O4-OVs/NC confirmed the transition from Fe2O3 to Fe3O4, along with the generation of oxygen vacancies, while preserving the original needle-like morphology of Fe2O3. Moreover, the results indicated the formation of the NC attaching to the surface of the formed Fe3O4 nanoparticles with a weight percent of ~13.6%. The synthesized nanocomposite was further employed as a heterogeneous Fenton catalyst to remove phenol from an aqueous solution. The material has shown excellent catalytic activity and stability, demonstrating a promising application for wastewater treatment. [ABSTRACT FROM AUTHOR]

Abstract: The binding of myricetin to lysozyme (Lys) in aqueous solution was investigated by fluorescence spectroscopy, ultraviolet–visible absorption spectroscopy (UV) and circular dichroism (CD) spectra under physiological conditions. There are also many metal ions present in body, thus the research about the effect of metal ions on the interaction of drugs with proteins is crucial. In this study, we have investigated the effect of both familiar metal ions Cu2+ and Fe3+ on the interaction between myricetin and Lys by using spectroscopy technique at pH 7.40, for the first time. Spectrophotometric observations are rationalized in terms of a static quenching process in a static quenching way. The cause of showing upward curvy patterns in Stern–Volmer plots was analyzed. The binding constants and binding sites of myricetin with Lys with or without Cu2+ and Fe3+ at different concentrations of myricetin were calculated. UV/vis measurements on the enzymatic activity of Lys with or without Cu2+ in the absence or presence of myricetin indicated that the interaction between myricetin and Lys led to a reduction in the activity of Lys. Furthermore, the effect of pH on the binding constant of myricetin with Lys was also examined. [Copyright &y& Elsevier]