A single-crystalline Bi2S3 nanowire array (Bi2S3NWA) is synthesized by an in situ hydrothermal reaction on the surface of a Bi2MoO6 film. As no additional source of Bi3+ is provided during the process, the Bi2MoO6 layer acts as the Bi3+ source for the synthesis of Bi2S3 nanowires. The fabricated Bi2MoO6/Bi2S3NWA electrode exhibited an increased photoelectrochemical (PEC) sulfite oxidation activity, which is attributed mainly to the effective interface obtained by the in situ hydrothermal growth, compared to other Bi2S3 electrodes. The generated electron from the Bi2S3 conduction band rapidly transfers to that of Bi2MoO6, yielding an enhanced electron separation of Bi2S3. Furthermore, the single-crystalline Bi2S3 nanowire can provide a fast electron pathway to Bi2MoO6 through its single domain, which also contributes to the improved PEC activity.

We describe a general approach for the synthesis of allylated and benzylated pyrazoles. An electron-withdrawing substituent, such as nitro, chloro, and ester groups, at C4 renders the Lewis basic nitrogen atom to be less basic and the C-H bond more acidic than the ones of the parent ring, enabling Pd-catalyzed C-H allylation and benzylation reactions of pyrazoles. The new method expanding the scope of the C-H functionalization of pyrazoles beyond arylation reactions provides a rapid access to complex pyrazole compounds.

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A palladium-catalyzed C-H arylation reaction of nitroimidazoles and nitropyrazoles was developed using aryl bromides as arene donors. The electron-withdrawing effect of the nitro group allows for direct C-H arylation reactions of the nitro diazoles with high regioselectivity under mild conditions. The new C-H arylation approach is thus complementary to nucleophilic substitution reactions, enabling the preparation of complex nitroazole compounds.

In this study, the reaction mechanisms of metal–semiconductor composites used as photocatalysts were demonstrated by first preparing bismuth vanadate (BiVO4) and then performing photodeposition of metal nanoparticles. The photocatalytic activity of metal–BiVO4 (M–BiVO4, where M = Pt, Au, Ag) composites were evaluated through dye decomposition under UV–vis irradiation. The photocatalytic efficiency was significantly enhanced after Pt deposition as compared to other M–BiVO4 composites. The size or shape of BiVO4 was not the main factor for the efficiency of Pt–BiVO4. However, a deposited Pt co-catalyst was essential for the photocatalytic decomposition of dye on the BiVO4 surface. Radical scavengers were employed to elucidate the reaction mechanism during the photocatalytic reaction with the Pt–BiVO4 composite. This study provides details on the reaction mechanism of the photocatalytic reaction on Pt at the BiVO4 surface under solar irradiation.