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Sodium‐ion batteries (SIBs) are promising alternatives to lithium‐ion batteries with similar working principles, cell structures, and material systems. However, attaining long‐term stability and high‐capacity performance of SIBs at ultrahigh rates remains a significant challenge due to the large ionic radius and slow kinetic behavior of Na+. Herein, a novel robust anode with a dual‐biomimetic gradient hierarchical architecture is proposed and provide a simple strategy to fabricate this sulfur‐doped mesoporous carbon concave hollow sphere/Ti3C2Tx MXene (SCMX) anode. In addition, Cu2S nanoparticles are in situ embedded into the SCMX architecture by electrochemical induction during the cycling process to act as active sites, which enhances the rate performance and cycling stability. Relying on its hybrid architecture and in situ formed Cu2S, this SCMX anode can achieve high ion accessibility, rich active sites, rapid charge transfer, and favorable structure stability, as disclosed by in/ex situ characterizations. As a result, it exhibits high reversible capacity (745.6 mAh g−1 at 0.2 A g−1), ultrahigh‐rate capability (380.5 mAh g−1 at 50.0 A g−1), and long cycling stability (98.2% capacity retention after 10 000 cycles at 80.0 A g−1). This work is anticipated to accelerate the development of high‐performance SIBs and offer distinctive inspiration for the design of electrode structures/systems. [ABSTRACT FROM AUTHOR]

A composite catalytic system using sulfur-vacancy-containing ZnIn2S4-Sv as a light-harvesting material and nickel-based polyoxometalate Na6K4[Ni4(H2O)2(PW9O34)2] (Ni4POM) as a co-catalyst was developed. The Ni4POM/ZnIn2S4-Sv composite gave a good hydrogen production rate of 337.5 μmol h−1, a value 11.8 times higher than that of ZnIn2S4-Sv. The direction of electron transfer, from ZnIn2S4-Sv to Ni4POM, was verified using surface photovoltage spectra. [ABSTRACT FROM AUTHOR]

A novel method for preparing chromones from α-diazo-flavanones has been developed. Good yields and regioselectivity are obtained through HCl catalysis and Rh2 (Oct)4 catalysis. The chromone obtained can undergo a one-pot Diels–Alder reaction to synthesize flavanone propellane in high yield. Mechanisms about 1,2-migration under both catalysts are proposed. [ABSTRACT FROM AUTHOR]

We have developed a convenient synthesis of a series of β-fluoramides in 65% yield. The process involved a tandem fluorination/Ritter reaction to synthesize β-fluoramides using α-diazo 2 H -benzopyran-4-one compounds. Selectfluor was used as the electrophilic fluoride source in acetonitrile to build the β-fluorinated quaternary carbon center and amide derivatives of 2 H -benzopyran-4-one in one step. The products N -(2-(2-fluoro-2,3-dihydro-3-oxobenzofuran-2-yl)propan-2-yl)acetamides were a series of bifunctional compounds with a 2-fluoro-2,3-dihydro-3-oxobenzofuran motif and amide groups.