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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]

In the synthesis of organic hybrid metal chalcogenides, piperazine (pip) has been widely applied as a template or charge-balancing agent in the structure assembly, but application of piperazine as a solvent to synthesize organic hybrid metal chalcogenides has not been reported. In this work, two new two-dimensional layered organic hybrid silver chalcogenidoantimonates, namely [pipH 2 ] 0.5 [Ag 2 SbS 3 ] (1), [pipH 2 ] 0.5 [Ag 2 SbSe 3 ] (2), have been synthesized by using piperazine as reaction medium. Both compounds possess the similar honeycombed anionic bilayers, and the biprotonated piperazine cations are resided between the bilayers. Thermal stabilities and optical properties of compounds 1 and 2 have been studied. Moreover, compounds 1 and 2 exhibited excellent photocatalytic activities for reducing aqueous Cr(VI) under visible light irradiation. [Display omitted] • Two new silver chalcogenidoantimonates were prepared by using piperazine as reaction medium. • Both compounds showed excellent photocatalytic activity for reducing Cr(VI) under visible light irradiation. • The effects of pH value and initial concentration on the catalytic performance were studied. [ABSTRACT FROM AUTHOR]

• Au@TiO 2 /Bi 2 WO 6 was synthesized by reverse micelle sol–gel method plus hydrothermal process. • Remarkable photocatalytic performance for degradation of antibiotics was achieved. • The Z-scheme charge transfer mechanism for Au@TiO 2 /Bi 2 WO 6 was verified. • The nanocomposite photocatalyst exhibited superior reusability. Semiconductor photocatalysis can be regarded as one of effective strategies to overcome the great challenges encountered with conventional technologies for environmental remediation. In this research, Z-scheme heterostructure composed of core–shell Au@TiO 2 nanoparticles and flower-like Bi 2 WO 6 nanosheets has been successfully prepared through the reverse micelle sol–gel method followed by a hydrothermal process. The structural characteristics, chemical compositions and photoelectrochemical properties of this ternary composite photocatalyst (Au@TiO 2 /Bi 2 WO 6) were further investigated in detail. Benefitted from the synergy of the heterojunction construction and metallic surface plasmon resonance effect, the Au@TiO 2 /Bi 2 WO 6 with an optimal mass ratio of Au@TiO 2 to Bi 2 WO 6 exhibited the significantly enhanced photocatalytic activity for degradation of antibiotics under visible-light irradiation, in which the degradation efficiency of sulfamethoxazole (SMX) and tetracycline hydrochloride (TC) could be up to 96.9% and 95.0% within 75 min, respectively. The reaction rate constant for SMX and TC degradation was calculated to be around 0.0425 min−1 and 0.0314 min−1, which has 7.2 times and 1.9 times enhancement compared with single Bi 2 WO 6 , respectively. In addition, the cyclic stability and photocatalytic mechanism of Au@TiO 2 /Bi 2 WO 6 were further verified. Our primary results provide a feasible strategy to develop core–shell heterostructured photocatalysts with superior performance for the efficient removal of low-concentration antibiotics in water. [ABSTRACT FROM AUTHOR]

The surface plasmon resonance (SPR) effect of noble nanometals can be utilized to effectively improve the catalytic performance of semiconductor photocatalysts. In this work, a novel composite photocatalyst of BiOBr microspheres simultaneously decorated by Ag and Bi dual nanoparticles (NPs) has been successfully synthesized by the hydrothermal method plus one-step reduction method. And the morphology, structure, chemical composition and photoelectrical properties of this composite photocatalyst (Ag/Bi–BiOBr) were further characterized. Due to the SPR effect of Ag and Bi dual NPs, Ag/Bi–BiOBr showed the high light absorption with narrow band gap, as well as fast charge separation via metal-semiconductor heterojunction so as to realize an efficient degradation of ibuprofen (IBP) under simulated solar irradiation. Through the further optimization of the loading amounts of Ag and Bi dual NPs, the excellent photocatalytic activity in the Ag/Bi–BiOBr has been achieved that 92.3% of IBP was removed within 60 min, which is among the best results reported so far for IBP degradation via photocatalysis. A facile preparation strategy of novel highly-active composite photocatalyst of BiOBr microspheres decorated by Ag and Bi dual nanoparticles has been proposed for efficient degradation of ibuprofen. • A simple one-step reduction strategy was proposed to prepare Ag/Bi dual nanoparticles-decorated BiOBr (Ag/Bi-BiOBr). • Bi nanoparticles were directly reduced from BiOBr without additional Bi precursors. • Ag and Bi nanoparticles increased the light absorbance and decreased the charge recombination. • The Ag/Bi-BiOBr showed efficient and stable photocatalytic activity on ibuprofen degradation. • The holes (h+) and electrons (e−) were the uppermost active species for ibuprofen degradation. [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]

Ultrathin TiO 2 nanosheet with abundant Ti3+ is constructed as a photocatalyst for CO 2 conversion in the absence of any sacrificial reagents. The exposed Ti3+ as a Lewis base site may activate CO 2 to form bridging Ti···CO 2 −···Ti, resulting highly CH 4 yield via the synergistic effect of coordination-activation and photocatalysis. • Ultrathin TiO 2 nanosheets (NST) with abundant Ti3+ sites are constructed as a photocatalyst for conversion CO 2. • The catalyst (NST) exhibits a high yield (147.2 μmol g−1 h−1) and selectivity (96.8 %) for CH 4. • CO 2 would be selectively activated on the surface of NST via forming the bridging Ti···CO 2 −···Ti coordination species. • The synergistic effect about coordination-activation and photocatalysis can greatly enhance CH 4 yield efficiency. Ultrathin TiO 2 nanosheet (NST) with abundant Ti3+ sites is developed as a photocatalyst which exhibits a high yield (147.2 μmol g−1 h−1) and selectivity (96.8%) for CO 2 to CH 4. The results of in situ FTIR, in situ EPR and density functional theory (DFT) calculation suggest that CO 2 would be selectively activated on NST surface via forming the bridging Ti···CO 2 −···Ti coordination species which not only lowers the activation energy barrier, but also determines the selectivity of CH 4. Additionally, NST with the better separation and transfer ability for photogenerated electrons-holes can fleetly supply the electrons to CO 2 molecules for high efficiently producing CH 4 via the Ti-C coordination bond. Finally, a possible mechanism of the synergistic effect about coordination-activation and photocatalysis is discussed at a molecule level. This work would offer a perspective for designing an effective photocatalyst and tailoring the selectivity of products by coordination activation. [ABSTRACT FROM AUTHOR]