Search

ZnIn2S4 is a promising candidate for photocatalysis. However, it is still facing great challenge to improve its photocatalytic activity through rationally regulating its microstructures. Herein, ZnIn2S4 micro-flowers with different self-assembly microstructures were synthesized by solvent induced through one-step hydrothermal method, and were used as catalytic dehydrogenation of 1,2,3,4-tetrahydroisoquinoline to 3,4-dihydroisoquinolines. Different solvents have great effects on the microstructure of ZnIn2S4. The surface of ZIS-H2O petals is relatively smooth, and the petals of ZIS-EtOH are micro-discoid and relatively rough. The microstructure of ZIS-EG is the smallest and consists of countless irregular thin nanosheet. The results show that ZIS-EG assembled with ethylene glycol as solvent has the best photocatalytic activity in the catalytic dehydrogenation. The maximum conversion of 98% as well as the selectivity of 99% of 3,4-dihydroisoquinolines was accomplished under air condition with 7-h visible-light irradiation. The excellent photocatalytic activity of ZIS-EG benefits from its excellent absorption of visible light as well as the separation efficiency of photogenerated carriers. Therefore, this work has provided an effectively method to accelerate the photocatalytic activity through solvent-induced controlling microstructures. A series of ZnIn2S4 photocatalysts with different microscopic morphologies were synthesized, and were used as catalytic dehydrogenation of 1, 2, 3, 4-tetrahydroisoquinoline to 3, 4-dihydroisoquinolines. The results show that ZnIn2S4 synthesized in ethylene glycol solvent has the best photocatalytic dehydrogenation activity. [ABSTRACT FROM AUTHOR]

Semiconductor magic-sized nanoclusters have got tremendous interests owing to their distinct chemical and photophysical properties, however, researches concerning their applications are still quite limited. Herein, we employ magic-sized CdSe nanoclusters as the light absorber for hydrogen photogeneration, which exhibits much better photocatalytic performance as compared to other conventional semiconductor quantum dots, such as CdS, CdSe, CdS/CdSe, and CdSe/CdS under identical conditions. Photoluminescence lifetime and transient absorption studies indicated that the superior activity is mainly ascribed to the longer exciton lifetime and fast electron transfer from nanoclusters to cocatalyst. Moreover, the issue of instability during reaction could be significantly inhibited by anchoring Zn2+ onto the surface of nanoclusters, which gives the average efficacy of hydrogen evolution at 0.61 ± 0.07 mL·h−1·mgcatalyst−1, i.e., 27.3 ± 2.9 mmol·h−1·gcatalyst−1 (420 nm) with maintained 95.2% of original activity over 12 h illumination. [ABSTRACT FROM AUTHOR]

In this work, pompon-like structured g-C3N4/ZnO composite photocatalyst was fabricated by a two-step method and characterized through different characterization tools to determine the photophysical properties. It is discovered that the synthesized pompon-like g-C3N4/ZnO photocatalyst is composed of flake g-C3N4 coated on the pompon surface of ZnO to form a heterojunction structure. In the composite photocatalyst, the pompon ZnO has large surface area (41.81 m2/g) which can provide more reactive sites for composite catalysts, the g-C3N4 can absorb the visible light which can effectively expand the absorption range of the composite, and the heterostructure formed between g-C3N4 and pompon ZnO can effectively reduce the coincidence efficiency of photo-generated carriers. The photocatalytic performance of pompon-like g-C3N4/ZnO photocatalyst was evaluated by photocatalytic degradation of rhodamine B (RhB) organic dyes under simulated solar light irradiation and the optimum doping amount of g-C3N4 is 10%. The stability of the composite photocatalyst was tested by five runs of RhB photodegradation under simulated visible light. [ABSTRACT FROM AUTHOR]