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The mechanism and enantiochemistry of non-C2-symmetric BINOLate titanium (1 : 1) catalyzed cyanation of aldehydes have been investigated using density functional theory (DFT). Calculation results suggest that the mononuclear titanium–BINOLate complex might be the dominant catalyst structure of this cyanation reaction. Using benzaldehyde as the substrate, the cyanation reaction could be completed via the bifunctional LALB mechanism or the Ti-HCN mechanism. For the bifunctional LALB mechanism, HCN needs to be isomerized to HNC under the catalysis of the imine N atom of imidazole firstly, then it attacks the carbonyl C atom to form the C–C bond, followed by a hydrogen transfer step to yield product cyanohydrins. For the Ti-HCN mechanism, following the formation of catalyst–HCN complexes is a decomposition step of HCN, and then the decomposed HCN directs the aldehyde to generate the final product via a concerted transition state. Computational results demonstrate that both isomerization and decomposition of HCN are predicted as the rate-determining steps of two reaction mechanisms. The enantioselectivity of the title reaction is mainly controlled by the energetic performance of the C–C bond-forming transition states, which is influenced greatly by the solvent effects. The calculation results show that the (S)-configuration product would be the predominant product in CH2Cl2, which is consistent with the experimental results. [ABSTRACT FROM AUTHOR]

Silver–zinc (Ag–Zn) batteries are regarded as a promising power source for flexible and wearable electronics due to their high safety, high energy density, and steady output voltage. However, the weak flexibility and poor cycle performance significantly limit the practical use of Ag–Zn batteries. In this work, we propose a novel flexible fibrous quasi-solid-state mild Ag–Zn battery with superb cycling performance by using a mild electrolyte and highly flexible binder-free electrodes. Carbon nanotube fibers serve as the current collector to improve the flexibility of flexible Ag–Zn cells. The mild electrolyte containing ZnCl2 and Na2SO4 not only prevents the dissolution of the Ag cathode but also impedes the heterogeneous growth of Zn dendrites. With 1500 cycles at 1 A g−1, the fibrous quasi-solid-state mild Ag–Zn battery achieves a remarkable capacity retention of 93.1%. Moreover, this novel flexible quasi-solid-state mild Ag–Zn battery can deliver a high capacity of 103.51 mA h g−1 at 0.1 A g−1. The fibrous quasi-solid-state mild Ag–Zn battery demonstrates remarkable flexibility and excellent bending ability (after 600 bending cycles with capacity retention of 89%). This pioneering work sheds light on the establishment of high-performance quasi-solid-state mild Ag–Zn batteries for burgeoning wearable electronics. [ABSTRACT FROM AUTHOR]

This paper reports on the preparation, characterization, and catalytic properties of the Pd@UIO-66 for toluene oxidation. The samples are prepared by the double-solvent method to form catalysts with large specific surface area, highly dispersed Pd0 (Elemental palladium) and abundant adsorbed oxygen, which are characterized by X-ray Photoelectron Spectroscopy (XPS), Brunauer-Emmett-Teller (BET) and Transmission Electron Microscopy (TEM). The results show that as the Pd content increases, the adsorbed oxygen content further increases, but at the same time Pd0 will agglomerate and lose some active sites, which will affect its catalytic performance. While 0.2%Pd@UIO-66 has the highest concentration of Pd0, the result shows it has the best catalytic activity and the T90 temperature is 210 °C. [ABSTRACT FROM AUTHOR]