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In this work, PCN-224(Fe) porphyrin-based metal–organic frameworks and a Poly(ionic liquids) (PILs) were used to prepare PCN-224(Fe)@PIL(Cl−) composite films by UV polymerisation. The structure, morphology, chemical composition, and electrochemical properties of the as-prepared composite film were investigated. PCN-224(Fe) was coated with a kind of P(1-vinylpyridinium chloride as monomer) on the outside to improve the electron transfer efficiency, while an electrochemical system was employed to catalysis the persulfate (PS) decomposition for the efficient degradation of tetracycline (TC). Because of the cathodic reduction reaction, the continuous redox cycle between Fe3+/Fe2+ was facilitated, which enhanced the degradation activity of persulfate on tetracycline. The PCN-224(Fe)@PIL(Cl−) composite demonstrated a superior electrocatalytic degradation efficiency of 95.8% in just 40 min for the TC model pollutant, surpassing the 63.3% efficiency of pure PCN-224(Fe) within 60 min. This work shows a successful example of using PILs to enhance catalytic degradation activity and points out a direction of preparation of catalysts for activating persulfate (PS). [ABSTRACT FROM AUTHOR]

The In2.77S4/In-MOFs Z-scheme heterojunction composite photocatalysts were successfully synthesized via an insitu hydrothermal growth method. The chemical structure, morphology, optical properties, and photogenerated carriers transfer behavior of the as-prepared In2.77S4/In-MOFs composites were characterized in details. The In2.77S4/In-MOFs (10 wt%) composite showed the optimal photocatalytic degradation efficiency of 95.9% in 90 min for the tetracycline (TC) model pollutant, which was significantly higher than that of pure In2.77S4 (75.1%) and In-MOFs (9.7%). The X-ray photoelectron spectrometer (XPS), photoelectrochemical, and electron paramagnetic resonance (EPR) technique were carried out to illuminate the photocatalytic degradation mechanism of In2.77S4/In-MOFs (10 wt%) for TC, which showed that the Z-scheme heterojunction structure of In2.77S4/In-MOFs (10 wt%) could reinforced the light harvesting capacity and promote the photogenerated carrier migration under visible light irradiation. Furthermore, the photogenerated holes play a major role during the photocatalytic degradation reaction. Finally, this work maybe offers an effective method for the designing In2.77S4-based Z-scheme heterojunctions to facilitate the charge carrier transfer in heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

In2.77S4 nanosheets were first synthesized and then used to construct the In2.77S4/COFs composite photocatalyst by an in situ hydrothermal growth method. The structure, optical properties, morphology, chemical composition and photo-generated carriers behavior of the as-synthesized In2.77S4/COFs composites were discussed, respectively. The tetracycline dilute solution was selected to evaluate its photocatalytic activity. Experimental results show that COFs can improve the photocatalytic activity and recyclability of In2.77S4 under visible light irradiation. With the increase in COFs dosage, the photocatalytic efficiency of the as-synthesized composite samples is first increased and then decreased. When the amount of COFs is 10 wt%, the as-synthesized In2.77S4/COFs composite photocatalyst shows the maximum photocatalytic degradation efficiency of 93.8% in 90 min, which is higher than that of 75.1% of In2.77S4 and 0.1% of COFs, respectively. Furthermore, the separation and migration efficiency of the photo-generated electron–hole pairs of the as-synthesized composite are improved in comparison of the pure samples and the transient photocurrent intensity of In2.77S4/COFs composite is about 2.5 times than that of pure In2.77S4 and 10 times than that of pure COFs. In addition, holes play a major role during the photocatalytic degradation process. [ABSTRACT FROM AUTHOR]

Semiconductor photocatalysis is a promising method to solve the problem of antibiotic pollution in water. A series of Bi2SiO5/BiVO4 composite photocatalysts for tetracycline and levofloxacin degradation are prepared by a two-step hydrothermal method. Analysis results show that the as-prepared Bi2SiO5/BiVO4 (2:3) hybrid exhibits better photocatalytic activity than pure samples under visible light illumination. The photocatalytic degradation efficiency of the as-prepared composite shows the maximum of 72.2% within 120 min for tetracycline, which is higher than 43.5% of pure Bi2SiO5 and 67.2% of pure BiVO4, respectively. Furthermore, it is 80.3% within 120 min for levofloxacin, which is higher than 7.6% of pure Bi2SiO5 and 69.7% of pure BiVO4, respectively. The formation of n–n isotype heterojunction at the interface of Bi2SiO5 and BiVO4 in the as-prepared composites causes to the improvement of the transport rate and separation efficiency of the photogenerated electron and hole pairs. In addition, the holes play a dominant role in the photocatalytic degradation process. This work will provide a reference for the study of visible light driven photocatalysts to solve antibiotics pollution in water. [ABSTRACT FROM AUTHOR]