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In this work, 0D/2D/2D Z-scheme AgVO 3 /RGO/C 3 N 4 blending porous PVDF photocatalytic self-cleaning membrane (AgVO 3 /RGO/C 3 N 4 -PVDF) were successfully fabricated. The AgVO 3 /RGO/C 3 N 4 -PVDF photocatalytic membranes have high efficiency for removing tetracycline and could synergistically separate and photocatalytic kill the E. coli. [Display omitted] The enhancement of the self-cleaning ability of photocatalytic membranes and their degradation efficiency over tetracycline (TC) still remains a challenge. In this study, an alternative silver vanadate quantum dots (AgVO 3 QDs) doped reduced graphene oxide (RGO) and graphitic carbon nitride (C 3 N 4) nanocomposites modified polyvinylidene fluoride (PVDF) membrane (AgVO 3 /RGO/C 3 N 4 -PVDF) was successfully fabricated to enhance the photocatalytic activity. The AgVO 3 /RGO/C 3 N 4 nanocomposites were functioned as the active component for the photocatalytic membrane. The unique Z-scheme heterostructure of AgVO 3 /RGO/C 3 N 4 and the porous PVDF framework synergistically enhanced the separation and transport efficiency of photogenerated carriers and facilitated the interaction between the photocatalyst and the pollutant. As a result, the degradation efficiency of TC for the AgVO 3 /RGO/C 3 N 4 -PVDF reached 88.53% within 120 min, which was higher than those of the binary component membranes (64.8% for RGO/C 3 N 4 -PVDF and 79.18% AgVO 3 /C 3 N 4 -PVDF). In addition, AgVO 3 /RGO/C 3 N 4 -PVDF exhibited high permeability (1977 L·m−2·h−1·bar−1) and excellent antifouling activity. Under visible-light irradiation, the flux recovery rate (FRR) increased from 92.4% to 99.1%. Furthermore, AgVO 3 /RGO/C 3 N 4 -PVDF could reject 97.4% of Escherichia coli (E. coli) owning to its self-cleaning capacity, and eliminated the E. coli under visible-light irradiation trough the photogeneration of h+. This study highlights a highly efficient photocatalytic membrane based on a Z-scheme heterostructure, which may have a great potential application in practical wastewater treatment. [ABSTRACT FROM AUTHOR]

A novel Z-scheme 2D/3D g-C 3 N 4 /BiOI-based beta-phase PVDF (β- phase PVDF) photocatalytic membranes were successfully synthesized via solvent crystallization and phase inversion method. The β -phase PVDF membrane with photocatalytic performance dramatically improved photocatalytic activity of Z-scheme 2D/3D g-C 3 N 4 /BiOI heterojunction. Designing photocatalytic membranes with excellent photocatalytic and self-cleaning ability based on the synergistic effect between the crystal structure of membrane matrix and photocatalyst is highly desirable. Herein, Z-scheme 2D/3D g-C 3 N 4 /BiOI heterojunction blended in beta-phase polyvinylidene fluoride membrane (β -phase PVDF) was prepared via solvent crystallization and phase inversion technique. As expected, the designed g-C 3 N 4 /BiOI/ β -phase PVDF photocatalytic membranes (CN/BI/ β- phase PVDF PMs) achieved exceptional photocatalytic degradation efficiency for tetracycline (94.6%) as compared to the CN/BI heterojunction power (84.0%) and two other control membrane matrixes (CN/BI/PAN and CN/BI/CA PMs) within 120 min. Meanwhile, the dynamic cyclic degradation system of CN/BI/ β- phase PVDF PMs was also investigated that reached to be 94.8% in 80 min. Besides, the CN/BI/ β- phase PVDF PMs not only had outstanding self-cleaning activity and remarkable permeability (up to 30,688 L·m−2·h−1) but also had high stability and reusability even after five runs. Importantly, the hydroxyl radical detection and ESR analysis identified that the β- phase PVDF membrane could promote photoinduced carrier separation efficiency of 2D/3D g-C 3 N 4 /BiOI heterojunction. This work may open up a novel strategy for designing and constructing high-efficient photocatalytic membranes for water treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] The scaffold materials with good mechanical and structural properties, controlled drug release performance, biocompatibility and biodegradability are important tenet in tissue engineering. In this work, the functional core–shell nanofibers with poly(ε -caprolactone) (PCL) as shell and silk fibroin heavy chain (H-fibroin) as core were constructed by emulsion electrospinning. The transmission electron microscopy confirmed that the nanofiber with core–shell structure were successfully prepared. The constructed nanofiber materials were characterized by the several characterization methods. The results showed that ethanol treatment could induce the formation of β -sheet of H-fibroin in composite nanofibers, thus improving the mechanical properties of PCL/H-fibroin nanofiber scaffold. In addition, we evaluated the potential of PCL/H-fibroin nanofiber membrane as a biological scaffold. It was found that PCL/H-fibroin nanofiber scaffold was more conducive to cell adhesion and proliferation with the increment of H-fibroin. Finally, in vitro drug release presented that PCL/H-fibroin core–shell nanofibers could effectively reduce the prophase burst of drug molecules and show the sustained drug release. The PCL/H-fibroin nanofiber scaffolds constructed in this work have good mechanical properties, biocompatibility, and display good potential in biomedical applications, such as drug carriers, tissue engineering and wound dressings, etc. [ABSTRACT FROM AUTHOR]

[Display omitted] Photothermal nanoreactor with rapid charge transfer and improved spectral utilization is a key point in photocatalysis research. Herein, silver sulfide quantum dots (Ag 2 S QDs) were coating on the surface of porous graphitic carbon nitride nano vesicles (PCNNVs) to form Ag 2 S/PCNNVs nanoreactors by a simple calcination method for obtaining efficient photothermal-assisted photocatalytic hydrogen (H 2) evolution under simulated/real sunlight irradiation. In particularly, the as-prepared optimal 3% Ag 2 S/PCNNVs sample exhibited the H 2 production rate of 34.8 mmol h−1 g−1, which was 3.5 times higher than that of bare PCNNVs. The enhancement of photothermal-assisted activity over the Ag 2 S/PCNNVs composite system is mainly attributed to the coupling of the photothermal conversion performance of Ag 2 S QDs and the thermal insulation performance of PCNNVs based on the plasmonic coupling-boosted photothermal nanoreactor. This study presents a promising strategy for the development of high-efficient photothermal-assisted photocatalysts. [ABSTRACT FROM AUTHOR]