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A highly selective, environmentally friendly, and scalable electrochemical protocol for the construction of α-acyloxy sulfides, through the synergistic effect of self-assembly-induced C(sp3)-H/O-H cross-coupling, is reported. It features exceptionally broad substrate scope, high regioselectivity, gram-scale synthesis, construction of complex molecules, and applicability to a variety of nucleophiles. Moreover, the soft X-ray absorption technique and a series of control experiments have been utilized to demonstrate the pivotal role of the self-assembly of the substrates, which indeed is responsible for the excellent compatibility and precise control of high regioselectivity in our electrochemical protocol.

Semiconductor photocatalysis is considered to be a promising technique to completely eliminate the organic pollutants in wastewater. Recently, S-scheme heterojunction photocatalysts have received much attention due to their high solar efficiency, superior transfer efficiency of charge carriers, and strong redox ability. Herein, we fabricated an S-scheme heterostructure BiOCl/MoSe2 by loading MoSe2 nanosheets on the surface of BiOCl microcrystals, using a solvothermal method. The microstructures, light absorption, and photoelectrochemical performances of the samples were characterized by the means of SEM, TEM, XRD, transient photocurrents, electrochemical impedance, and photoluminescence (PL) spectra. The photocatalytic activities of BiOCl, MoSe2, and the BiOCl/MoSe2 samples with different MoSe2 contents were evaluated by the degradation of methyl orange (MO) and antibiotic sulfadiazine (SD) under simulated sunlight irradiation. It was found that BiOCl/MoSe2 displayed an evidently enhanced photocatalytic activity compared to single BiOCl and MoSe2, and 30 wt.% was an optimal loading amount for obtaining the highest photocatalytic activity. On the basis of radical trapping experiments and energy level analyses, it was deduced that BiOCl/MoSe2 follows an S-scheme charge transfer pathway and •O2−, •OH, and h+ all take part in the degradation of organic pollutants.

LaNbO4: Nd3+/Yb3+/Ho3+ phosphors with various concentrations of Nd3+, Yb3+ and Ho3+ were prepared by a traditional high temperature solid-state reaction method. The crystal structure of the as-prepared samples was characterized by X-ray diffraction (XRD) and the results showed that monoclinic LaNbO4 samples were obtained. Green and red up-conversion (UC) emissions of Ho3+ were observed under the excitations of 808 nm and 980 nm. Concentration dependent studies indicated that Nd3+ and Yb3+ played different roles in the UC emissions of Ho3+ under different wavelength excitations. The same optimal concentrations of Yb3+ and Ho3+ ions were obtained when excited by 808 nm and 980 nm lasers. The UC luminescence mechanisms under different excitation sources were discussed by detecting the UC luminescence intensity related to the laser pumped power density. The energy transfer efficiencies from Nd3+ to Yb3+ and Yb3+ to Ho3+ were confirmed via lifetime measurement. By comparing with the commercial green NaYF4: Er3+/Yb3+ UC luminescence phosphor, the UC luminescence performance of Ho3+ doped sample was evaluated. The results showed that LaNbO4: Nd3+/Yb3+/Ho3+ phosphors had excellent green UC luminescence properties under both 808 nm and 980 nm excitations.

An efficient synthesis of 3-halo-3-arylacrylonitrile is described from the direct addition between cyanoalkynes and inorganic alkaline metal halides such as LiCl, LiBr and KI in good to satisfactory yields. No transition metal is needed for the synthesis of iodo- and bromo-products, although Pd catalyst is used to accelerate the chloro-product.

An electrochemical oxidative difunctionalization of allyl alcohols for the synthesis of β-trifluoromethyl ketones is achieved through a 1,2-migration process. A series of β-trifluoromethyl ketones can be facilely obtained utilizing CF3SO2Na as a radical source, eliminating the use of metals and sacrificial chemical oxidants. Importantly, this protocol not only realizes aryl migration but also offers alkyl-migration products. Additionally, an electrochemically catalyzed ring expansion and gram-scale reaction demonstrated the synthetic usefulness of this protocol.