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The production of singlet oxygen during advanced oxidation processes is restricted by the precise cooperation of photogenerated carriers, energy band potentials, and surface adsorbed oxygen. Herein, we report that an in situ BiVO4/Bi4Ti3O12 S-scheme heterojunction could form oxygen vacancies by constructing crystal defects and effectively produce singlet oxygen by adsorbing oxygen on the surface. Moreover, the novel S-scheme heterojunction not only facilitates the separation of charge carriers, but also accumulates photogenerated electrons on the conduction band of the BiVO4 nanosheet, and the interaction rate between photogenerated electrons and oxygen adsorption on the surface is improved, which tremendously prolongs the life span of the singlet oxygen. Consequently, the selective oxidation of singlet oxygen was examined by the catalysis of the obstinate aromatic hydrocarbon pollutant, and BiVO4/Bi4Ti3O12, which additionally produced the singlet oxygen, showed superior catalytic performance in comparison with the pristine BiVO4. This study overcomes the current limitation of singlet oxygen production and provides a promising strategy for the development of novel catalysts. [ABSTRACT FROM AUTHOR]

A versatile metal- and base-free direct reductive amination of aldehydes with amines using formic acid as a reductant under the catalysis of inexpensive BF3·Et2O has been developed. A wide range of primary and secondary amines and diversely substituted aldehydes are compatible with this transformation, allowing facile access to various secondary and tertiary amines in high yields with wide functional group tolerance. Moreover, the method is convenient for the late-stage functionalization of bioactive compounds and preparation of commercialized drug molecules and biologically relevant N-heterocycles. The procedure has the advantages of simple operation and workup and easy scale-up, and does not require dry conditions, an inert atmosphere or a water scavenger. Mechanistic studies reveal the involvement of imine activation by BF3 and hydride transfer from formic acid. [ABSTRACT FROM AUTHOR]

Photocatalytic performance is influenced by two contradictory factors, which are light absorption range and separation of charge carriers. Loading noble metals with nanosized interfacial contact is expected to improve the separation and transfer of photo-excited charge carriers while enlarging the light absorption range of the semiconductor photocatalyst. Therefore, it should be possible to improve the photocatalytic performance of pristine nontypical stoichiometric semiconductor photocatalysts by loading a specific noble metal. Herein, a series of novel Pt-Bi 4 V 2 O 11 photocatalysts have been successfully prepared via a surface reduction technique. The crystal structure, morphology, and photocatalytic performance, as well as photo-electron properties of the as-synthesized samples were fully characterized. Moreover, the series of Pt-Bi 4 V 2 O 11 samples were evaluated to remove typical organic pollutants, rhodamine B and enrofloxacin, from aqueous solutions. The photoluminescence, quenching experiments and the electron spin resonance technique were utilized to identify the effective radicals during the photocatalytic process and understand the photocatalytic mechanism. The photocatalytic performance of Pt-Bi 4 V 2 O 11 was tremendously enhanced compared with pristine Bi 4 V 2 O 11 , and there was additional ˙O 2- produced during the photocatalytic process. This study deeply investigated the relation between the separation of charge carriers and the light harvesting, and revealed a promising strategy for fabricating efficient photocatalysts for both dyes and antibiotics., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)