Nonradical-based advanced oxidation processes for pollutant removal have attracted much attention due to their inherent advantages. Herein we report that magnesium oxides (MgO) in CuOMgO/Fe3O4 not only enhanced the catalytic properties but also switched the free radical peroxymonosulfate (PMS)-activated process into the 1O2 based nonradical process. CuOMgO/Fe3O4 catalyst exhibited consistent performance in a wide pH range from 5.0 to 10.0, and the degradation kinetics were not inhibited by the common free radical scavengers, anions, or natural organic matter. Quantitative structure–activity relationships (QSARs) revealed the relationship between the degradation rate constant of 14 substituted phenols and their conventional descriptor variables (i.e., Hammett constants σ, σ–, σ+), half-wave oxidation potential (E 1/2), and pK a values. QSARs together with the kinetic isotopic effect (KIE) recognized the electron transfer as the dominant oxidation process. Characterizations and DFT calculation indicated that the incorporated MgO alters the copper sites to highly oxidized metal centers, offering a more suitable platform for PMS to generate metastable copper intermediates. These highly oxidized metals centers of copper played the key role in producing O2 •– after accepting an electron from another PMS molecule, and finally 1O2 as sole reactive species was generated from the direct oxidation of O2 •– through thermodynamically feasible reactions.

Photocatalytic isomerization of thermodynamically stable E-alkene to less stable Z-alkene has been the subject of numerous studies, being successfully achieved mainly under UV irradiation. Recent development of visible light photoredox catalysis has witnessed it emerging as a powerful tool for the access of new structural complexity and many challenging targets. Herein, we report a visible light-promoted E to Z isomerization of cinnamates. When E-isomer of cinnamates was irradiated with blue light in the presence of an organo-photocatalyst, fac-Ir(ppy) 3 , Z-isomer was exclusively obtained in high yields and with good selectivity. The mild, convenient reaction condition has made this protocol an effective synthetic methodology, which was subsequently implemented in an efficient synthesis of coumarins.

Transition-metal sulfides (TMSs) are considered excellent anode materials for sodium-ion batteries by virtue of decent capabilities based on multielectron conversion reactions. Herein, N-doped carboncoated CuS nanowires (CuS NWs@NC) were facilely fabricated via a refluxing method, following in situ dopamine polymerization and sulfidation process. Employed as anodes for SIBs, the CuS NWs@NC deliver a highly invertible capacity of 571.1 mA h g −1 after 100 cycles at 0.2 A g −1 and a competitive rate capability of 294.4 mA h g −1 even at 20 A g −1 . Remarkably, they exhibit a competitive long-life cyclic stability (216.7 mA h g −1 at 20 A g −1 , 81.7% capacity retention over 10,000 cycles). Furthermore, the galvanostatic intermittent titration technique test reveals that the unique nanoarchitecture boosts the Na + diffusion ability, guaranteeing superb cyclability and exceptional rate performance. Finally, a NVP/C||CuS NW@ NC full battery was facilely constructed, which demonstrates a steady capacity of 220 mA h g −1 at 0.2 A g −1 over 200 cycles. The superior sodium storage performance is likely due to the one-dimensional coaxial core−shell nanoarchitecture and synergistic effect of the inner CuS nanowires with the outer conductive nitrogen-doped carbon layer, which provide a highway for fast electron/ion transport, restrain stress and agglomeration of CuS during cycling, and offer a significant capacitive-controlled capacity contribution. This scalable design provides a new strategy for improving the sodium storage property of other TMSs.

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It is challenging to explore non-noble metal-based electrocatalysts with high-performance and long-term stability for oxygen evolution reaction (OER). Herein, urchin-like iron-doped nickel cobalt phosphide (FeNiCoP) with hierarchical nanoarray structures and fine-tuned doped Fe content is fabricated through a simple hydrothermal method and subsequent phosphorization process. The optimized FeNiCoP manifests outstanding OER electrocatalytic performance in an alkaline electrolyte with a low overpotential of 259 mV at 10 mA·cm–2 and a Tafel slope of 40 mV·dec–1, which is superior to the benchmark IrO2 and nickel cobalt phosphide (NiCoP) catalysts. The electrochemical activity of NiCoP can be improved by regulating the content of doped Fe. The enhanced catalytic performance of FeNiCoP can be ascribed to the unique urchin-like structure and electronic interaction among Fe, Ni, and Co elements, which expose more active sites, facilitate ion diffusion and gas release, optimize the electronic structure, and thereby enhance OER catalytic performances. Above all, these indicate that the as-prepared FeNiCoP with excellent activity and stability may be a good alternative to commercial precious metal-based catalysts.