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Here, the zinc sulfide–copper sulfide (ZnS–CuS) nanocomposites have been synthesized using immersing thin layers of ZnS in 0.5 (M) Copper (II) chloride solution at low temperature by a simple and cost-effective chemical bath deposition (CBD) method. The immersion time of ZnS thin films in copper (II) chloride solution was investigated based on the structural, morphological, optical and optical catalytic activity of the prepared layers. The results of X-ray diffraction (XRD) and transmission electron microscopy (TEM) confirmed the formation of CuS: ZnS nanolayers consists of nanocrystals with an approximate diameter of less than 10 nm during the immersion time of 1 min. The particles forming the layers are dense and have good adhesion to the substrate. The energy gap of the layers decreases with increasing copper, which can lead to phase formation. Their significant photocatalytic activities in the photodegradation of Rhodamine B (RhB) dye in aqueous media have been considered, because ZnS:CuS nanocomposite thin films showed light catalytic activity in the RhB degradation in presence of visible radiation, so that the percentage of dye degradation is decreased by increasing the amount of copper and the duration of exposure to visible light due to slowing down the recombination rate of electron–hole pairs. While investigating the optical catalytic activity of the layers, there was no need to homogenize and centrifuge the solution to separate the nanoparticles from it. The main aim of this study is consideration of the effects of CuS amount on the photocatalytic activity of ZnS–CuS nanocomposite under the CBD method of synthesis condition. [ABSTRACT FROM AUTHOR]

Textile wastewater becomes the primary root of environmental pollution due to the rapid infection rates of freshwater, subsurface water, soil, and air. Due to the high absorption abilities of UV and visible light, polymer nanocomposite photocatalyst films (PNPFs) are recognized as potential candidates for textile wastewater treatment. Here, we developed novel cobalt monoxide (CoO)/polyaniline (PANI) PNPFs with high photocatalytic efficiency and stability. The photocatalytic efficiencies of PANI/CoO films were estimated utilizing the degradation of organic dyes and real-textile wastewater (RTW) under various lighting conditions. PANI/CoO PNPF completely decomposed methylene blue and RTW samples in 30 and 45 min under UV light illumination, respectively. We found that the CoO nanoparticles doubled the PANI's photocatalytic decomposition rate. However, under visible light irradiation, their photocatalytic efficiencies almost halved. Moreover, PANI/CoO PNPF exhibited excellent photocatalytic stability by maintaining the photocatalytic performance for up to five cycles with over 95% removal efficiency. This study yielded an efficient and alternative polymer nanocomposite to decompose wastewater sources contaminated with various textile dyes and may be examined for industrial-scale applications in the future. [ABSTRACT FROM AUTHOR]

Photocatalytic degradation of organic dyes in less-toxic products under visible light irradiation is considered a green method which is widely used in this field. In this manuscript, a novel coordination polymer (PUCP1) based hybrid-nanocomposite (PUCP1@rGO) was synthesized. The PUCP1 and nanocomposite were successfully characterized by using various analytical techniques such as SCXRD, FT–IR, PXRD, TGA, FE–SEM, BET and XPS. The PUCP1 exhibits a 2D framework with an uninodal 4-connected net and sql topology. The PUCP1@rGO was applied as a sensitive and selective photocatalyst for significant degradation of Safranin-O (SO) dye. The rGO played an important role in the expansion of photocatalytic activity of the PUCP1 by inhibiting the recombination probability of electron–hole pairs. The results revealed that PUCP1@rGO nanocomposite can degrade 76% of SO dye in only 90 min under visible light at a neutral pH. The PUCP1@rGO was found very sensitive to photocatalytic degradation of SO dye because a very small amount of catalyst (i.e. 10 mg) degrades the 5 μM concentration of SO dye in the presence of light. The PUCP1@rGO is a reusable photocatalyst for up to 5 cycles. Rarely, any sensitive photocatalyst for SO dye is reported in literature than PUCP1@rGO which degrades SO dye in a very small period with significant quantity. Thus, PUCP1@rGO can be used as a promising photocatalyst for the degradation of SO dye. In this work, we have synthesized a novel coordination polymer (PUCP1) and nanocomposite (PUCP1@rGO) by impreganation of rGO in PUCP1 framework.The PUCP1 exhibited selective photocatalytic response towards safranin-O dye under visible light irradiation and impregnation of rGO enhance the photocatalytic properties of PUCP1@rGO nanocomposite as compared to parent PUCP1.The PUCP1@rGO nanocomposite degrade the safranin-O dye up to 76% in 90 min only under visible light. [ABSTRACT FROM AUTHOR]

The pyrolysis of melamine was an effective one-pot method for preparing a nanostructured multifunctional photocatalytic based on core/shell g-C3N4@TiO2 heterojunction. Various techniques entirely characterized these materials: X-ray diffraction (XRD) proved to enhance the as-prepared materials' crystallinity through the variation of dislocation, strain, and crystallite size with TiO2 loading. The stacked layered/sheet-like with a smooth surface of the as-prepared samples have been shown via scanning electron microscopy (SEM). Diffuse reflectance spectroscopy (DRS) showed an apparent decrease in the energy bandgap for these nanocomposites with TiO2 loading. All the prepared materials were subjected to visible photocatalytic applications under the same conditions. The dye model (Methylene Blue, MB), and antibiotic model (Amoxicillin, AMO), was photodegraded using the as-prepared nanocomposites under visible light irradiation. In the recombination reduction among TiO2 and g-C3N4 interfaces, g-C3N4 has been effectively utilized as a matrix. Our findings proved that g-C3N4@TiO2 photocatalysts exhibited superior photocatalytic performance. CNT-5 of 2.58 eV bandgap had a higher activity of 99.7 in 50 min for MB and 100% in 20 min for AMO than the other represented photocatalysts in this work. The migration of photogenerated electrons from a g-C3N4 to TiO2 via heterojunction among them as g-C3N4 (1 0 1) removes the electrons accumulated on (1 0 1) of TiO2, improve the photodegradation efficiency. Therefore, the increase in photocatalytic reaction rates, recycling, and the sample's photostability can be considered the result of successful interactions among the TiO2 and g-C3N4 systems. The suggested photodegradation mechanism of MB and AMO was discussed in detail and compared with previously reported work. Therefore, the photodegradation rate of MB and AMO via CNT-5 composite is 6 and 3 times, respectively, higher than that of g-C3N4 under simulated solar irradiation. This research creates a new perspective on the production of nanocomposite materials in the area of treatment of pharmaceutical and dye contaminants. [ABSTRACT FROM AUTHOR]

A novel bismuth vanadate–silicon dioxide–graphene oxide (BiVO4/SiO2/GO) nanocomposite was synthesized successfully by using hydrothermal method. The as-prepared nanocomposite was characterized by various techniques, including X-ray diffraction (XRD), field emission scanning electron microscope (SEM), and Brunauer–Emmett–Teller (BET). The photocatalytic activity of nanoparticles was evaluated by measuring the removal efficiency of methylene blue (MB) in aqueous solution under visible light irradiation. The results indicated that BiVO4, BiVO4/SiO2, and BiVO4/SiO2/GO exhibited the same diffraction peaks of monoclinic scheelite structure due to the higher content of BiVO4 in the nanocomposite system. The BiVO4 and BiVO4/SiO2 were uniformly agglomerated from irregular particles with the different level of aggregation and the size of several micrometers. In the meantime, BiVO4 and SiO2 particles were adhered firmly on the GO sheets in BiVO4/SiO2/GO nanocomposite. The BiVO4/SiO2/GO nanocomposite showed a much higher efficiency than the pure BiVO4 and the BiVO4/SiO2 hybrid material for MB removal efficiency due to the considerably increased specific surface area and pore size by the adhesion of BiVO4 and SiO2 on GO sheets. [ABSTRACT FROM AUTHOR]

In this research work we report on the preparation of TiO2/Fe3O4/AgI multicomponent photocatalysts for decontamination of various organic dyes via photocatalysis process under visible illumination. The chemical and physical features of the prepared photocatalysts were characterized by XRD, UV–Vis DRS, SEM, EDX, FT-IR, BET, VSM, and PL analyses. The TiO2/Fe3O4/AgI (30%) photocatalyst displayed the highest photodegradation ability for RhB, Eosin-Y, and fuchsine, which was about 75.3, 35.3, 21.8-times greater than that of the TiO2, 26.2, 20.8, and 10.5-folds as high as that of the TiO2/Fe3O4 samples, respectively. This improved photocatalytic activity is related to the formation of n–n heterojunction between two semiconductor, broader visible light spectrum response, and diminished charge carriers recombination. Scavenging experiments confirmed that the .O2−, h+, and .OH are reactive species in RhB photodegradation process. Moreover, the TiO2/Fe3O4/AgI (30%) nanocomposite exhibited greatly stable recycling activity. Finally, a plausible photocatalytic mechanism has been proposed based on the experimental results. This research suggests a facile method to design the magnetically separable nanocomposites based on TiO2 with significant photoactivity under visible irradiation. [ABSTRACT FROM AUTHOR]

In this work, for the first time, magnetic NiFe2O4@ZnO nanocomposite was synthesized using tragacanth gel by the novel sol-gel method. NiFe2O4@ZnO magnetic nanocomposite was investigated using powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), vibrating sample magnetometer (VSM), Transmission electron microscopy (TEM), Field emission scanning electron microscopy (FESEM) and energy dispersive X-ray analysis (EDX). The NiFe2O4@ZnO MNCs exhibit ferromagnetic behavior at room temperature, with a saturation magnetization of 15.22 emu/g and a coercivity of 150 Oe. XRD results show that NiFe2O4@ZnO nanocomposite corresponds to the hexagonal wurtzite of ZnO and the spinel cubic structure of NiFe2O4. The present magnetic nanocomposite displays high photocatalytic activity for the removal of direct blue 129 dye and reactive blue 21 dye under irradiation with visible light. The results demonstrated that the catalyst can degrade ca. 98% of the direct blue 129 and ca. 96% of the reactive blue 21 dyes. The current nanocomposite can be separated from the reaction mixture using an external permanent magnet and its high performance saved even after recycling fifth times. [ABSTRACT FROM AUTHOR]