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Developing a novel and highly efficient catalytic oxidation system for environmental protection was an important task. In this work, inspired by the photocatalytic system and peroxydisulfate (PDS) system, the magnetic γ‐Fe2O3/h‐BN composite was designed for synergetic catalytic. The tetracycline was selected to study the degradation activity of all‐obtained samples. Among, the sample with a weight ratio of 7 % has the optimum catalytic performance. The enhanced catalytic performance was attributed to the separation of electron‐hole pairs and contact with pollutant of γ‐Fe2O3/h‐BN composite. Under visible‐light illumination, the γ‐Fe2O3/h‐BN composite could generate superoxide free radicals (O2.−)) and holes (h+) to decompose pollutant, while the addition of PDS, the PDS would excite to generate hydroxyl radicals (⋅OH) and sulfate radicals (SO4.−) for further degrading pollutant. Under optimal condition, the degradation rate reached 90 % within 90 min. In addition, the investigation of tetracycline (TC) degradation under different experimental conditions (pH, catalyst dosage, PDS concentration, various salt) was conducted. This study provided a novel synergetic catalytic system for wastewater treatment. [ABSTRACT FROM AUTHOR]

To completely utilize the high redox ability of photo-induced charge carriers. Here, a Z-scheme photocatalyst of TiO 2 QDs/Bi 12 TiO 20 (TBT) composites with TiO 2 QDs fragment attached to the surface of Bi 12 TiO 20 (BTO) was prepared and the photocatalytic activity was evaluated by degradation of gatifloxacin (GF). The optimal photocatalytic performance of TBT displayed 3 times higher than bare BTO. The improved photocatalytic performance was ascribed to the effective separation of the charge carriers between TiO 2 QDs and BTO via the direct Z-scheme heterojunction. Such a strategy for the construction of Z-scheme TBT composites for removal of organic pollutants, proving new insights into design photocatalyst. • A TiO 2 quantum dots fragment was prepared and covered on the surface of Bi 12 TiO 20. • A Z-scheme heterojunction was formed between TiO 2 QDs and Bi 12 TiO 20. • The TOQs played as the sensitizer to increase the photocatalytic activity. [ABSTRACT FROM AUTHOR]

Abstract In this work, two Bi-based semiconductors composites was synthesized through the BiVO 4 quantum dots (BVO QDs) was grown on the Bi 12 TiO 20 (BTO) via an in-suit growth with the ultrasonic method, which was more stability and evenly dispersed. As expected, the BVO-BTO composites exhibited increased visible-light-driven photocatalytic performance for photo-degradation due to the advantages of BVO QDs. Moreover, the possible mechanism of BVO-BTO composites was studied by trapping experiment, photocurrent, UV–vis and so on. The results demonstrated that the BVO QDs can widen the light response range to visible region and hasten the charge transfer and separation. Thus, the photocatalytic activity was enhanced through the BVO QDs decorated on BTO, which provided a new idea for designing Bi-based materials. Highlights • Two Bi-based materials were used to design the BiVO 4 quantum dots/Bi 12 TiO 20 composites. • The in-suit growth with the ultrasonic method was benefit to stability and dispersed. • The BVO-BTO composites have a better light response and electron transfer. [ABSTRACT FROM AUTHOR]

• Black Bi 4 Ti 3 O 12 nanosheet was synthesized. • Black Bi 4 Ti 3 O 12 have oxygen vacancy and disorder layer. • Black Bi 4 Ti 3 O 12 exhibited extend light absorption and high photocatalytic activity. In this work, a simple method to prepare defect two-dimension (2D) Bi 4 Ti 3 O 12 nanosheets material by NaBH 4 reduction with Argon atmosphere was reported. The results of EPR and XPS demonstrated that the presence of oxygen vacancy in Bi 4 Ti 3 O 12 , which resulted in color changed and extend photon-absorbance. By comparing to pristine Bi 4 Ti 3 O 12 , the black Bi 4 Ti 3 O 12 exhibited higher photocatalytic activity to pollutants. The mechanism was also proposed for exploring the defect in the photocatalytic process. [ABSTRACT FROM AUTHOR]

A hollow fluorescence sensor of H-ZIF-8/CDs@MIPs was designed with biomass CDs and ZIF-8, which showed a better selectively and sensitivity towards BHb in real samples. [Display omitted] • The leaves were used for the preparation fluorescence carbon dots. • A hollow fluorescence sensor was designed for the detection of hemoglobin. • The unique fluorescence sensor has the potential for detecting hemoglobin in bovine urine. To develop non-toxic, highly efficient and selective fluorescence sensors was a significance research. In this work, a novel hollow fluorescence sensor was designed with biomass carbon dots (CDs), ZIF-8 and molecularly imprinted polymers (MIPs) via aqueous polymerization. The results demonstrated such unique structure fluorescence sensor exhibited fast response time, excellent stability and highly selectively towards bovine hemoglobin (BHb). Even in a complex environment, the hollow fluorescence sensor (H-ZIF-8/CDs@MIPs) still has a good recognition effect on BHb. Under an optimized condition, the hollow fluorescence sensor was quenched linearly with BHb concentration in the range of 0.058–4.5 μM with the detection limit of 15.6 nM. In addition, a possible quenching mechanism of hollow fluorescence towards BHb was confirmed resonance energy transfer (FRET). In the actual application process, the hollow fluorescence sensor showed a better detection performance towards BHb with the recoveries ranged of 98.6–101.1 %. This work provided a strategy to design green and unique hollow fluorescence sensor for practical application. [ABSTRACT FROM AUTHOR]

• CsPbBr 3 QDs were successfully adhered to BN nanosheets by an easy heterogeneous nucleation method. • The improving stability of CsPbBr 3 @BN sensor was realized by the protection of BN nanosheets for CsPbBr 3 QDs. • The fluorescence of CsPbBr 3 @BN sensor could be sensitively quenched by tetracycline through electron transfer process. The abuse of tetracycline (TC) antibiotics would seriously affect human health and hence the detection had become essential. Here, we had constructed a hydrophobicity of fluorescence sensor based on the excellent photoluminescence emission of CsPbBr 3 QDs and the hydrophobic ability of Boron Nitride (BN). This design effectively solved the instability of CsPbBr 3 QDs and realized the sensitive detection of TC. Under optimum conditions, the linear range of TC was 0–0.44 mg L−1 with the 6.5 μg L−1. Furthermore, the sensor was successfully used for the recognition of TC in honey and milk samples. This work also provided an ideal for designing CsPbBr 3 QDs-based on fluorescence sensor. [ABSTRACT FROM AUTHOR]