Preparation, characterization and photocatalytic performance of heterostructured AgCl/Bi2WO6 microspheres

Green synthesis of Ag, Se, and Ag2Se nanoparticles by Pseudomonas aeruginosa: characterization and their biological and photocatalytic applications

Nanoparticles have drawn significant interest in a range of applications, ranging from biomedical to environmental sciences, due to their distinctive physicochemical characteristics. In this study, it was reported that simple biological production of Ag, Se, and bimetallic Ag2Se nanoparticles (NPs) with Pseudomonas aeruginosa is a promising, low-cost, and environmentally friendly method. For the first time in the scientific literature, Ag2Se nanoparticles have been generated via green bacterial biosynthesis. UV-vis spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and EDX were used to characterize the produced NPs. Biosynthesized NPs were examined for antibacterial, antibiofilm, and photocatalytic properties, and it was determined that the effects of NPs were dose dependent. The biosynthesized AgNPs, SeNPs, and Ag2Se NPs showed anti-microbial activity against Escherichia coli and Staphylococcus aureus. Minimal inhibitory concentrations (MICs) of E. coli and S. aureus were between 150 and 250 µg/mL. The NPs showed antibiofilm activity against E. coli and S. aureus at sub-MIC levels and reduced biofilm formation by at least 80% at a concentration of 200 µg/mL of each NPs. To photocatalyze the breakdown of Congo red, Ag, Se, and Ag2Se NPs were utilized, and their photocatalytic activity was tested at various concentrations and intervals. A minor decrease of photocatalytic degradation was detected throughout the NPs reuse operation (five cycles). Based on the encouraging findings, the synthesized NPs demonstrated antibacterial, antibiofilm, and photocatalytic properties, suggesting that they might be used in pharmaceutical, medical, environmental, and other applications.

A straightforward synthesis of visible light driven BiFeO3/AgVO3 nanocomposites with improved photocatalytic activity

Herein, an efficient visible-light-driven BiFeO₃/AgVO₃ nanocomposite was effectively fabricated via a facile co-precipitation procedure. The physicochemical properties of BiFeO₃/AgVO₃ nanocomposites were investigated via Fourier transform-infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL), UV visible diffuse reflectance spectroscopy (DRS) and photoelectrochemical studies (PEC). The photocatalytic activity (PCA) of BiFeO₃/AgVO₃ nanocomposites was assessed with regard to the photocatalytic degradation of Rhodamine-B (RhB) when subjected to visible light irradiation (VLI). Upon 90 min of illumination, the optimal 3%-BiFeO₃/AgVO₃ nanocomposite showed a greater photocatalytic degradation, which was ∼3 times higher than the bare AgVO₃. The lower PL intensity of 3%-BiFeO₃/AgVO₃ nanocomposite exposed the low recombination rate, which improved the photo-excited charge carriers separation efficiency. The experimental outcomes showed that the BiFeO₃/AgVO₃ nanocomposite might be an encouraging material for treatment of industrial and metropolitan wastewater. Moreover, a plausible RhB degradation mechanism was proposed proving the participation of the generated OH and O₂^- radicals in the degradation over BiFeO₃/AgVO₃ nanocomposite.

Synthesis of efficient photocatalysts from sodium bentonite modified Bi2WO6 for the decomposition of oilfield pollutants

Bi₂WO₆ is modified to give sodium bentonite/Bi₂WO₆ photocatalyst, prepared by hydrothermal synthesis. We offer a new approach for selecting carrier modified photocatalysts, and show the degradation of oil field pollutants using this photocatalyst.

A Facile Synthesis of Visible-Light Driven Rod-on-Rod like α-FeOOH/α-AgVO3 Nanocomposite as Greatly Enhanced Photocatalyst for Degradation of Rhodamine B

In this work, we have synthesized the rod-on-rod–like α-FeOOH/α-AgVO3 nanocomposite photocatalysts with the different amounts of solvothermally synthesized α-FeOOH nanorods via a simple co-precipitation method. The as-synthesized photocatalysts were characterized by X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, UV−Visible diffuse reflectance spectroscopy, scanning electron microscopy (SEM), element mapping, high-resolution transmission electron microscopy (HR-TEM) and X-ray photoelectron spectroscopy (XPS) analysis. The observed SEM images show that both α-AgVO3 and α-FeOOH exhibits the rod-shaped morphology with nano size. Furthermore, the photocatalytic activities of the obtained photocatalysts were evaluated towards the degradation of Rhodamine B (RhB) under visible-light irradiation. It is demonstrated that the 3 mg α-FeOOH added to the α-FeOOH/α-AgVO3 nanocomposite exhibited an enhanced photocatalytic performance as compared with the pure α-AgVO3 and α-FeOOH. This significant improvement can be attributed to the increased photo-excited electron-hole pair separation efficiency, large portion of visible-light absorption ability and the reduced recombination of the electron-hole pair. The recycling test revealed that the optimized nanocomposite exhibited good photostability and reusability properties. In addition, the believable photodegradation mechanism of RhB using α-FeOOH/α-AgVO3 nanocomposite is proposed. Hence, the developed α-FeOOH/α-AgVO3 nanocomposite is a promising material for the degradation of organic pollutants in an aqueous environment.

Review on nanoscale Bi-based photocatalysts

Nanoscale Bi-based photocatalysts are promising candidates for visible-light-driven photocatalytic environmental remediation and energy conversion. However, the performance of bulk bismuthal semiconductors is unsatisfactory. Increasing efforts have been focused on enhancing the performance of this photocatalyst family. Many studies have reported on component adjustment, morphology control, heterojunction construction, and surface modification. Herein, recent topics in these fields, including doping, changing stoichiometry, solid solutions, ultrathin nanosheets, hierarchical and hollow architectures, conventional heterojunctions, direct Z-scheme junctions, and surface modification of conductive materials and semiconductors, are reviewed. The progress in the enhancement mechanism involving light absorption, band structure tailoring, and separation and utilization of excited carriers, is also introduced. The challenges and tendencies in the studies of nanoscale Bi-based photocatalysts are discussed and summarized.

Facile one-step hydrothermal synthesis of noble-metal-free hetero-structural ternary composites and their application in photocatalytic water purification

The development of heterostructured and metal decorated photocatalysts using a relatively simple, efficient and economical one-step strategy is crucial for commercial applications.

A novel Nb2O5/Bi2WO6 heterojunction photocatalytic oxidative desulfurization catalyst with high visible light-induced photocatalytic activity

A novel Nb₂O₅/Bi₂WO₆ heterojunction catalyst was synthesized and applied in PODS of DBT. It shows higher activity than pure Nb₂O₅ and Bi₂WO₆ in visible light induced PODS of DBT, in which holes and superoxide radicals are the main reactive species.

Preparation of heterostructured Ag@AgCl/La2Ti2O7 plasmonic photocatalysts with high visible light photocatalytic performance for the degradation of organic pollutants

In this work, Ag@AgCl modified La₂Ti₂O₇ plasmonic photocatalysts were prepared by a simple and feasible two-step process.