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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]

Semiconducting photocatalysts composited with noble nanometals can be regarded as one of effective strategies to enhance the photocatalytic activity, attributed to a synergy of heterojuction formation and surface plasmon resonance effect. However, the dosage of nanometal in the composite for achieving an optimal performance is commonly larger than 10 wt%, causing high cost in raw materials. In this work, a composite photocatalyst of flower-like bismuth tungstate (Bi 2 WO 6) nanosheets decorated by low-dosage silver nanoparticles (Ag NPs) with the excellent photocatalytic activity for sulfamethoxazole (SMX) degradation was prepared. Further, the morphological and structural characteristics, chemical compositions, and photoelectrical properties of this composite photocatalyst (Ag/Bi 2 WO 6) were investigated. Different loading amounts of Ag NPs (1, 3 and 5 wt%) in Ag/Bi 2 WO 6 were modulated, and when the dosage of Ag NPs was controlled to be only 3 wt%, the composite photocatalyst exhibited the most efficient degradation that 95.04% of SMX was removed within 60 min under visible light irradiation, which has around 3 times enhancement compared to single Bi 2 WO 6. The sacrificial agent experiment indicated that •O2− and •OH are the main active substances in the photocatalytic degradation of SMX. And the cyclic experiment further confirmed the Ag/Bi 2 WO 6 composite with high stability and reusability. The photocatalytic mechanism was verifiably proposed that the enhanced degradation performance was derived from more effective light absorption and photogenerated charge separation by loading Ag NPs onto Bi 2 WO 6. Our primary results provide a basic platform for exploring the high catalytic-activity photocatalysts with low-dosage noble nanometals. [ABSTRACT FROM AUTHOR]