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Highly efficient photocatalysts can be fabricated using favorable charge transfer nanocomposite channel structures. This study adopted pulsed laser ablation in liquid (PLAL) to obtain rGO-bridged TiO2/g-C3N4 (rGO-TiO2/g-C3N4) photocatalytic Z-scheme without the need for noble metals. In addition to evaluating the resulting nanocomposite's (comprising rGO nanosheets, TiO2 nanotubes, and g-C3N4 nanosheets) CO2 reduction effectiveness, its chemical, morphological, structural, and optical characteristics were examined using various analytical techniques. The findings revealed a synergistic interaction between g-C3N4 and TiO2, suggesting the presence of unique interfacial bonding, as well as enhanced visible light absorption. Notably, the ternary rGO-TiO2/g-C3N4 Z-scheme exhibits an excellent photocatalytic performance by photocatalytically converting CO2 into CO and CH4, with 81% selectivity towards the CO and 1.91% apparent quantum efficiency at 420 nm. Thus, the findings can pave the way for various Z-scheme systems in wide photocatalytic applications.
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Nitrate pollution of water emerging from various anthropogenic activities has become a major environmental concern because of its deleterious effects on natural water resources. The present work deals with the synthesis of the ternary nanocomposite based on chitosan, iron oxide (Fe3O4), and titanium dioxide (TiO2) and its application for the removal of nitrates from model-contaminated water. Fe3O4 derived through a coprecipitation method was incorporated into the chitosan matrix which was fabricated in the form of beads. The wet gel beads were then successfully coated with sol-gel-derived silver-doped titanium dioxide sol followed by drying under suitable conditions to get the functional nanocomposite beads. The synthesized functional materials were further characterized for their structural, morphological, and textural features using X-ray diffraction analysis, physical property measurement (PPMS), Fourier transform infrared (FTIR) analysis, UV visible spectroscopy analysis (UV-vis), BET surface area analysis (BET), field emission scanning electron microscopic (FESEM), and transmission electron microscopy (TEM) analysis. The ternary nanocomposites were further used for the removal of nitrates via adsorption cum photocatalytic reduction technique from the model contaminated water when subjected to an adsorption study under dark conditions and photocatalytic study under UV/visible/sunlight for a definite time. Fe3O4 in the nanocomposite provides enhanced adsorption features whereas the functional coating of titanium dioxide aids in the removal of nitrates through the photocatalytic reduction technique. The functional beads containing 3% Fe3O4 in the wet gel form (CTA-F3) have excellent nitrate removal efficiency of ~ 97% via adsorption cum solar photocatalysis towards the removal of nitrate ions from 50 ppm nitrate solution, whereas the dried nanocomposite beads have got a nitrate removal efficiency of ~ 68% in 1 h from 100 ppm nitrate solution. Continuous flow adsorption cum photocatalytic study was performed further using the oven-dried functional beads in which flow rate and bed height were varied while maintaining the concentration of feed solution as constant. A nitrate removal efficiency of 65% and an adsorption capacity of 4.1 mgg-1 were obtained for the CTA-F3 beads in the continuous flow adsorption cum photocatalysis experiment for up to 5 h when using an inlet concentration of 100 ppm, bed height 12 cm, and flow rate 5.0 ml min-1. A representative fixed-bed column adsorption experiment conducted using CTA-F3 beads for the treatment of a real groundwater sample shows reasonable results for nitrate removal (71.7% efficiency) along with a significant removal rate for the other anions as well. Thus, the novel adsorbent/photocatalyst developed is suitable for the removal of nitrates from water due to the synergistic effect between Fe3O4, chitosan, and titanium dioxide.
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Quitosana , Nanocompostos , Nitratos , Titânio , Poluentes Químicos da Água , Nanocompostos/química , Titânio/química , Nitratos/química , Adsorção , Quitosana/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Catálise , Compostos Férricos/químicaRESUMO
We have adopted a novel CeO2/Bi2MoO6/g-C3N4-based ternary nanocomposite that was synthesized via hydrothermal technique. The physiochemical characterization of as-prepared samples was examined through various analytical techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy TEM, photoluminescent spectra (PL), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET), and ultraviolet diffuse reflectance spectroscopy (UV-DRS) technique. In addition, the photocatalytic performance was carried out by degradation of Rhodamine B dye under visible light irradiation using this nanocatalyst. The ternary nanocomposite achieved 94% of the degradation efficiency within 100 min which is higher than the pristine and binary composites under the predetermined condition pH = 7, Rhodamine B dye = 5 mg/L, and catalyst concentration = 150 mg/L. The experimental synergetic effect of CeO2/Bi2MoO6/g-C3N4 ternary nanocomposite has been ascribed to the interfacial charge carrier migration between CeO2, Bi2MoO6, and g-C3N4. The optical absorption range of CeO2/Bi2MoO6/g-C3N4 ternary nanocomposite was enhanced, and the band gap was reduced up to 2.2 eV. In addition, scavenger trapping experiment proves that the super oxide anions (O2-.) and photogenerated holes are the major active species. The reusability and stability experiment proved the CeO2/Bi2MoO6/g-C3N4 ternary nanocomposite keeps good durability during the photocatalytic degradation process after the five successive cycles. Furthermore, based on the results, the charge carrier transfer photocatalytic mechanism was also discussed. This CeO2/Bi2MoO6/g-C3N4 ternary nanocomposite may offer the cheapest material and extend the great opportunity for clean and environmental remediation approach under the visible light irradiation.
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Cério , Rodaminas , Rodaminas/química , Cério/química , Catálise , Nanosferas/química , Bismuto/química , Poluentes Ambientais/química , Nanocompostos/química , Molibdênio/químicaRESUMO
In this research, we report an enhanced sensing response ethanol gas sensing device based on a ternary nanocomposite of molybdenum diselenide-zinc oxide heterojunctions decorated rGO (MoSe2/ZnO/rGO) at room temperature. The sensing performance of the ternary nanocomposite sensing device has been analysed for various concentrations of ethanol gas (1-500 ppm). The gas-sensing results have revealed that for 500 ppm ethanol gas concentration, the sensing device has exhibited an enhanced response value(Rg/Ra)of 50.2. Significantly, the sensing device has displayed a quick response and recovery time of 6.2 and 12.9 s respectively. In addition to this, the sensing device has shown a great prospect for long-term detection of ethanol gas (45 days). The sensing device has demonstrated the ability to detect ethanol at remarkably low concentrations of 1 ppm. The enhanced sensing performance of the ternary nanocomposite sensing device has highlighted the effective synergistic effect between MoSe2nanosheets, ZnO nanorods, and rGO nanosheets. This has been attributed to the formation of two heterojunctions in the ternary nanocomposite sensor: a p-n heterojunction between MoSe2and ZnO and a p-p heterojunction between MoSe2and rGO. The analysis of the results has suggested that the proposed MoSe2/ZnO/rGO nanocomposite sensing device could be considered a promising candidate for the real-time detection of ethanol gas.
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This work aimed to investigate photocatalytic properties of GQDs@PEG@Mg-ZnFe2O4 nanocomposite, composed of graphene quantum dots (GQDs), polyethylene glycol (PEG), and Mg-ZnFe2O4, for the degradation of methylene blue (MB) and crystal violet (CV). This nanocomposite was synthesized using facile ultrasonics-assisted methodology. XRD analysis confirmed the formation of the spinel structure of the Mg-ZnFe2O4 in the nanocomposite, whereas the presence of GQDs and PEG was confirmed by Fourier transform infrared spectroscopy. Scanning electron microscopy (SEM) revealed a reduction in agglomeration and particle size in the ternary nanocomposite. The GQDs@PEG@Mg-ZnFe2O4 nanocomposite demonstrates a remarkable degradation efficiency of 98 % for CV and MB dyes in the presence of sunlight in 120 min, indicating its potential as an efficient photocatalyst. Vibrating sample magnetometer (VSM) analysis confirmed the superparamagnetic behavior of the GQDs@PEG@Mg-ZnFe2O4 nanocomposite which enables magnetic recovery of the photocatalyst after the degradation process. Overall, this study emphasizes the utilization of an environmentally friendly approach to effectively eliminate organic pollutants from wastewater, addressing a crucial environmental concern.
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With the rapid development of nanotechnology, the study of nanocomposites as electrode materials has significantly enhanced the scope of research towards energy storage applications. Exploring electrode materials with superior electrochemical properties is still a challenge for high-performance supercapacitors. In the present research article, we prepared a novel nanocomposite of tungsten trioxide nanoparticles grown over supported graphene oxide sheets and embedded with a poly(3,4-ethylenedioxythiophene) matrix to maximize its electrical double layer capacitance. The extensive characterization shows that the poly(3,4-ethylenedioxythiophene) matrix was homogeneously dispersed throughout the surface of the tungsten trioxide-graphene oxide. The poly(3,4-ethylenedioxythiophene)@tungsten trioxide-graphene oxide exhibits a higher specific capacitance of 478.3 F·g-1 at 10 mV·s-1 as compared to tungsten trioxide-graphene oxide (345.3 F·g-1). The retention capacity of 92.1% up to 5000 cycles at 0.1 A·g-1 shows that this ternary nanocomposite electrode also exhibits good cycling stability. The poly(3,4-ethylenedioxythiophene)@tungsten trioxide-graphene oxide energy density and power densities are observed to be 54.2 Wh·kg-1 and 971 W·kg-1. The poly(3,4-ethylenedioxythiophene)@tungsten trioxide-graphene oxide has been shown to be a superior anode material in supercapacitors because of the synergistic interaction of the poly(3,4-ethylenedioxythiophene) matrix and the tungsten trioxide-graphene oxide surface. These advantages reveal that the poly(3,4-ethylenedioxythiophene)@tungsten trioxide-graphene oxide electrode can be a promising electroactive material for supercapacitor applications.
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The ubiquitous and refractory benzophenone (BP)-type ultraviolet filters, which are also endocrine disruptors, were commonly detected in the aquatic matrix and could not be efficiently removed by conventional wastewater treatment processes, thus causing extensive concern. Herein, a novel ternary nanocomposite, P-g-CN/α-Bi2O3/WO3 (P-gBW), was successfully fabricated by mixing cocalcinated components and applied to the decomposition of BP-type ultraviolet filters. The dual-Z-scheme heterostructure of P-gBW enhances visible-light absorption, efficiently facilitates separation and mobility, and prolongs the lifetime of photoinduced charge carriers via double charge transfer mechanisms. The optimum 95 wt% P-gBW exhibited excellent photocatalytic activity, degrading 96% 4-hydroxy benzophenone (4HBP) within 150 min and 93% 2,2',4,4'-tetrahydroxybenzophenone (BP-2) within 100 min under visible-light illumination, respectively. The pseudo-first-order rate constant of 4HBP (1.15 h-1) was 6.8-, 3.1-, 3.3- and 2.2-fold higher than those of WO3, P-g-CN, α-Bi2O3, and P-g-CN/α-Bi2O3, respectively, while that of BP-2 (1.71 h-1) was 5.2-, 2.2-, 3.2- and 1.5-fold higher, respectively. The improved photocatalytic degradation was attributed to efficient photoinduced charge carrier separation and migration and prevented the recombination of electron holes, as verified by photoluminescence, transient photocurrent response, and electrochemical impedance spectroscopy. Trapping experiments, electron paramagnetic resonance, and band energy position indicated an efficient dual-Z-scheme heterostructure.
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Benzofenonas , Luz , Iluminação , Espectroscopia de Ressonância de Spin EletrônicaRESUMO
The impact of ZnO/SnO2/reduced graphene oxide nanocomposites (ZnO/SnO2/rGO NCs) for improved photocatalytic degradation of organic dye pollution is examined in this study. The developed ternary nanocomposites had a variety of characteristics that were detected, such as crystallinity, recombination of photogenerated charge carriers, energy gap, and surface morphologies. When rGO was added to the mixture, the optical band gap energy of ZnO/SnO2 was lowered, which improved the photocatalytic activity. Additionally, in comparison to ZnO, ZnO/rGO, SnO2/rGO samples, the ZnO/SnO2/rGO nanocomposites demonstrated exceptional photocatalytic effectiveness for the destruction of orange II (99.8%) and reactive red 120 dye (97.02%), respectively after 120 min exposure to sunlight. The high electron transport properties of the rGO layers, which make it feasible to efficiently separate electron-hole pairs, are attributed to the enhanced photocatalytic activity of the ZnO/SnO2/rGO nanocomposites. According to the results, synthesized ZnO/SnO2/rGO nanocomposites are a cost-efficient option for removing dye pollutants from an aqueous ecosystem. Studies show that ZnO/SnO2/rGO nanocomposites are effective photocatalysts and may one day serve as the ideal material to reduce water pollution.
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Poluentes Ambientais , Nanocompostos , Óxido de Zinco , EcossistemaRESUMO
Currently, nanomaterials with exceptional antibacterial activity have become an emerging domain in research. The optimization of nanomaterials against infection causing agents is the next step in dealing with the present-day problem of antibiotics. In this research work, Ag2O, CoFe2O4, and Ag2O/CoFe2O4/rGO are prepared by chemical methods. Ag2O was prepared by co-precipitation method, while solvothermal technique was utilized for the synthesis of CoFe2O4. The ternary nanocomposite was synthesized by a simple in situ reduction using a two-step approach. The structural and morphological properties were studied by UV-Vis spectroscopy, X-ray diffraction spectroscopy (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (SEM), dynamic light scattering (DLS), and Fourier-transform infrared spectroscopy (FTIR). From the X-ray diffraction analysis, the crystallite size is found to be 14 nm, 5 nm, and 6 nm for Ag2O, CoFe2O4, and Ag2O/CoFe2O4/rGO respectively. The synthesized nanomaterials were investigated for antibacterial activities against gram-positive strain Staphylococcus aureus (S. aureus) and gram-negative strain Escherichia coli (E. coli) using Agar well diffusion method. Ag2O and CoFe2O4 showed zones of inhibition (ZOI) of 13 mm and 11 mm against gram positive bacteria while 12 mm against gram negative bacteria respectively, while ternary nanocomposite showed 14 mm and 13 mm of ZOI. The antibacterial activity of nanomaterials showed a gradual increment with an increase in the concentration of the materials. Ag2O, CoFe2O4, and Ag2O/CoFe2O4/rGO showed minimum inhibitory concentration (MIC) values of 4.5, 6.5, and 4.5 µg/mL for S. aureus and 6.5, 7.2, and 4.8 µg/mL for E. coli respectively. Minimum bactericidal concentrations were found to be same as the MIC values. Additionally, a time-kill curve analysis was performed and for ternary nanocomposite; the killing response was most effective as the complete killing was achieved at 3 h of incubation at 3-MIC (9.75 µg/mL). These results demonstrate that all the nanomaterials, as a kind of antibacterial material, have a great potential for a wide range of biomedical applications.
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Grafite , Nanopartículas Metálicas , Staphylococcus aureus , Escherichia coli , Antibacterianos/farmacologia , Antibacterianos/química , Grafite/química , Testes de Sensibilidade Microbiana , Nanopartículas Metálicas/químicaRESUMO
Herein, the ternary CdS/BiVO4/g-C3N4 (CBG) hybrid semiconductor photocatalyst was prepared via a hydrothermal technique. The synthesized photocatalysts were thoroughly characterized using powder XRD, XPS, FTIR, SEM, TEM, and UV-DRS to investigate the microstructural, morphological attributes, and optical properties. The photocatalytic activity of the ternary CBG hybrid semiconductor was assessed through the photodegradation of Methylene Blue (MB) aqueous dye under visible light. The outcomes exhibited that the CBG hybrid semiconductor showed excellent photocatalytic activity (about 94.5% after 120 min) compared to the results obtained with the pristine materials or the other composite (CdS/BiVO4). The enhancement of photocatalytic activity can be due to the construction of heterojunctions among g-C3N4, CdS, and BiVO4, which improves charge transfer efficiency and hence favors the degradation of organic dyes. Moreover, the as-prepared photocatalyst showed excellent stability after five cycles, indicating good stability and reusability. Subsequently, a possible photocatalytic mechanism was proposed based on the experimental results. The current investigation provides a promising strategy to promote photocatalytic activity to eliminate waterborne contaminants.
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Azul de Metileno , Nanocompostos , Luz , CorantesRESUMO
The thermoelectric (TE) performance of conducting polymers can be improved by the incorporation of carbon nanomaterials. In this work, the impact of carbon black (CB) on polypyrrole (PPy) and polypyrrole/polyaniline (PPy/PANI) binary composite have been investigated. Herein, PPy/PANI binary composite was initially prepared through chemical oxidative polymerization and then solution mixed with CB to form PPy/PANI/CB ternary nanocomposite. The structural and morphological analyses confirmed the formation of composites, and the strong interaction present between polymer matrix and CB. This was further confirmed by theoretical study, which showed strong noncovalent interaction and high complex stability between the materials. The thermoelectric results showed that both the electrical conductivity (σ) and Seebeck coefficient (S) has been increased with the increase in CB content (from 10 wt% to 30 wt%) and temperature (303 K to 373 K), while the thermal conductivity (κ) increase was low. The ternary nanocomposite involving 30 wt% of CB was found to be the most promising material which showed an enhanced power factor (PF) of 0.0251 µW/mK2 and high figure of merit (ZT) of 4.37x10-5 at 370 K. The enhancement in ZT for PPy/PANI/CB ternary composite is 2 times, 316 times, 17.3 times, 3.97 times, 11.7 times, and 6.8 times greater than other samples. The enhancement in power factor and ZT was due to energy filtering effect and strong non-covalent interactions between the homopolymers and CB.
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This paper introduces a high-performance self-powered nitrogen dioxide gas sensor based on Pd-modified ZnO/MoSe2 nanocomposites. Poly(vinyl alcohol) (PVA) nanofibers were prepared by high-voltage electrospinning and tribological nanogenerators (TENGs) were designed. The output voltage of TENG and the performance of the generator at different frequencies were measured. The absolute value of the maximum positive and negative voltage exceeds 200 V. Then, the output voltage of a single ZnO thin-film sensor, Pd@ZnO thin-film sensor and Pd@ZnO/MoSe2 thin-film sensor was tested by using the energy generated by TENG at 5 Hz, when the thin-film sensor was exposed to 1-50 ppm NO2 gas. The experimental results showed that the sensing response of the Pd@ZnO/MoSe2 thin-film sensor was higher than that of the single ZnO film sensor and Pd@ZnO thin-film sensor. The TENG-driven response rate of the Pd@ZnO/MoSe2 sensor on exposure to 50 ppm NO2 gas was 13.8. At the same time, the sensor had good repeatability and selectivity. The synthetic Pd@ZnO/MoSe2 ternary nanocomposite was an ideal material for the NO2 sensor, with excellent structure and performance.
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The synthesis of a photo-catalyst with a narrow bandgap and efficient capability to degrade contaminants in the presence of sunlight is currently challenging but exciting. In this work, an efficient photocatalytic ternary nanocomposite g-C3N4/Cu@CdS has been synthesized successfully by using the co-precipitation method. The synthesized composite was then characterized by SEM, XRD studies, EDX analysis, and ultra-violet-visible (UV-VIS) spectroscopy. The catalytic efficiency for the methylene blue (MB) dye and drug degradation (ciprofloxacin) was assessed by UV-visible absorption spectra. Gram-positive and Gram-negative bacteria were used to test the fabrication composite's antibacterial properties. Various compositions (1%, 3%, 5%, 7%, and 9%) of/Cu@CdS nanocomposite (NCs) and 20%, 30%, 40%, 50%, and 60% of g-C3N4 NCs were prepared. Results reveal that 5%Cu@CdS and 40%g-C3N45%Cu@CdS showed maximum antibacterial activity and photocatalytic degradation of dye and drug. The X-ray pattern showed no remarkable change in doped and pristine CdS nanoparticles (NPs). The efficient photocatalytic degradation activity of the fabricated ternary nanocomposite against MB dye and ciprofloxacin an antibiotic drug makes it a viable contender for solving environmental problems.
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In this work, a novel ternary nanocomposites AgZnS-TiO2-reduced graphene oxide (RGO) was successfully synthesized by a facile soft ultrasonic-reduction condition as low as 70 °C. During the ultrasound reaction, the reduction of GO and the growth of AgZnS and TiO2 crystals occurred simultaneously in conjunction with the deposition of AgZnS and TiO2 crystals onto the surface of the graphene. The synthesized nanocatalysts were characterized by XRD, SEM, TEM, EDX, Raman spectroscopy, XPS, UV-Vis DRS, photoluminescence spectrometer, and photocurrent and CV. The AgZnS-G-T was shown as catalytic HER with some synnegetic factors such as pH-universal, temperature, and ultrasonic condition. After 4 h, it was observed that AgZnS-TiO2-RGO has the highest efficiency of photocatalytic activity through hydrogen production by water splitting, which achieved the highest hydrogen evolution rate of 930.45 µmol/g at buffer solution (pH = 5), which was superior to AgZnS-G (790.1 µmole/g) and AgZnS (701.2 µmole/g). Such a significant hydrogen evolution amount far exceeded that of undoped TiO2 and RGO. The H2 evolution amounts increased significantly at ultrasonic irradiation power of 80 MHz. AgZnS-G-T demonstrates the higher H2 evolution amounts of 985 µmole/g at 80 MHz. Its photocatalytic hydrogen-evolution activity remained at a high level over four cycles (16 h) nanoparticle.
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We report a simple strategy to grow a novel cobalt nickel vanadium oxide (CoxNiVyOz) nanocomposite on bare and reduced-graphene-oxide (rGO)-coated nickel foam (Ni foam) substrates. In this way, the synthesized graphene oxide is coated on Ni foam, and reduced electrochemically with a negative voltage to prepare a more conductive rGO-coated Ni foam substrate. The fabricated electrodes were characterized with a field-emission scanning electron microscope (FESEM), energy-dispersive X-ray spectra (EDX), X-ray photoelectron spectra (XPS), and Fourier-transform infrared (FTIR) spectra. The electrochemical performance of these CoxNiVyOz-based electrode materials deposited on rGO-coated Ni foam substrate exhibited superior specific capacitance 701.08 F/g, which is more than twice that of a sample coated on bare Ni foam (300.31 F/g) under the same experimental conditions at current density 2 A/g. Our work highlights the effect of covering the Ni foam surface with a rGO film to expedite the specific capacity of the supercapacitors. Despite the slightly decreased stability of a CoxNiVyOz-based electrode coated on a Ni foam@rGO substrate, the facile synthesis, large specific capacitance, and preservation of 92% of the initial capacitance, even after running 5500 cyclic voltammetric (CV) scans, indicate that the CoxNiVyOz-based electrode is a promising candidate for high-performance energy-storage devices.
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Sustainable wastewater treatment is crucial to remediate the water pollutants through the development of highly efficient, low-cost and separation free photocatalyst. The aim of this study is to construct a novel CoNiO2-BiFeO3-NiS ternary nanocomposite (NCs) for the efficient degradation of organic pollutants by utilising visible light. The NCs was characterized by various physiochemical techniques, including HR-TEM, SEM, XPS, FT-IR, ESR, EIS, PL, UV-visible DRS, and N2 adsorption and desorption analysis. The photocatalyst exhibits extraordinary degradation efficiency towards MO (99.8%) and RhB (97.8%). The intermediates were determined using GC-MS analysis and the degradation pathway was elucidated. The complete mineralization was further confirmed by TOC analysis. The CoNiO2-BiFeO3-NiS ternary NCs have shown excellent photostability, structural stability and reusability even after six cycles and it is confirmed by XRD and XPS analysis. The kinetic study reveals that the photodegradation of the dyes follows first order reaction. The influence of different pH, dye concentrations and NCs dosages were investigated. The intermediate toxicity was predicted by computational stimulation using ECOSAR software. The NCs shows promising potential for ecological safety which demonstrates its practical application in the treatment of waste water pollutants in large scale.
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Nanocompostos , Poluentes Químicos da Água , Compostos Azo , Catálise , Corantes/química , Cinética , Luz , Nanocompostos/química , Rodaminas , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/químicaRESUMO
In this work, we reported the successful synthesis of novel Ag/TiO2 /CuFe2 O4 ternary nanocomposite by hydrothermal technique by using TiO2 /CuFe2 O4 binary nanocomposite precursor that was also prepared by hydrothermal treatment by using TiO2 nanoparticles and CuFe2 O4 nanoparticles synthesized via sol-gel method. The synthesized nanomaterials were accessed for their morphological, structural, and optical properties. X-ray diffraction (XRD) study reveals the formation of pure Ag/TiO2 /CuFe2 O4 ternary nanocomposite in which the Ag, TiO2 , and CuFe2 O4 are in anatase, spinal, and cubic crystal phases, respectively. Transmission electron microscopy (TEM) and high-resolution TEM (HRTEM) analyses of Ag/TiO2 /CuFe2 O4 ternary nanocomposite indicated granule-shaped morphology with bright spots of silver. The existence of Ti, O, Cu, Fe, and Ag without any other elements in the energy-dispersive X-ray spectroscopy (EDS) spectra of the prepared ternary nanocomposite depict its purity and its polycrystalline nature was confirmed by its selected area electron diffraction (SAED) pattern. The ternary nanocomposite was utilized for the methylene blue dye degradation with an optimum dose of 1.00 g/100 ml under ultraviolet (UV) light; the enhanced photocatalytic activity of the composite is attributed mainly due to the appreciable magnitudinal difference of positive charge of the valence band and negative charge of the conduction band of TiO2 and CuFe2 O4 ; meanwhile, the interfacially placed Ag acts as a sink for the elections. Also, the ternary nanocomposite showed satisfactory antibacterial activities. PRACTITIONER POINTS: The prepared ternary nanocomposite showed effective results in dye degradation and satisfactory antibacterial property. The concentration of methylene dye has decreased considerably in every degradation process which was accessed through UV-vis studies. The highest degradation by using the ternary nanocomposite archived at pH = 6 Appreciable antibacterial activity was achieved against a few Gram-positive strains and Gram-negative strains of bacteria. This research activity can open a broad area of research towards textile dye degradation and antibacterial studies.
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Azul de Metileno , Nanocompostos , Antibacterianos/química , Antibacterianos/farmacologia , Catálise , Azul de Metileno/química , Nanocompostos/química , Titânio/química , Titânio/farmacologiaRESUMO
In account of environmental remediation, an ideal photocatalyst was fabricated for the effective treatment of water systems. Herein, dual heterojunctions framed CuWO4/Bi2WO6/MnS nanocomposite (NCs) was synthesized via simple co-precipitation method followed by ultra-sonicated assisted route. The prepared NCs were investigated its photocatalytic degradation performance using para-chlorophenol (4-CP) and reduction of chromium VI (Cr (VI)) under visible light irradiation. The photocatalyst were characterized by various analytical techniques including XRD, HR-TEM, XPS, UV-vis DRS, FE-SEM, EIS, PL, ESR, Raman and N2 adsorption and desorption studies. The excellent photodegradation of 4-CP was observed within 180 min by the NCs. Similarly, the Cr (VI) reduction was about 97% within 140 min. The effect of pH and influence of different dosage of NCs and 4-CP on the photodegradation efficiency was investigated. The reusability and stability of the NCs was examined over 6 consecutive runs where the XRD and XPS confirm the structural stability of the prepared NCs. The scavenging experiment were carried out to elucidate the mechanism and the active species involved were O2-⢠and OH⢠radicals. The TOC analysis affirmed the complete mineralization of the prepared NCs. The ecotoxicity analysis was carried out to determine the toxicity effect of intermediates using ECOSAR software and the end product toxicity was also evaluated against E. coli and S. epidermis. The end product toxicity study also confirmed that the degraded product was less toxic compared to parent compound. Further, the genotoxicity study was done to understand the environmental impact using allium cepa and results confirms that there are no causes of cytotoxicity & genotoxicity by the prepared NCs. Therefore, the prepared NCs can be economical, efficient with excellent photocatalytic performance and environment friendly.
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Clorofenóis , Recuperação e Remediação Ambiental , Nanocompostos , Poluentes Químicos da Água , Catálise , Clorofenóis/toxicidade , Cromo , Escherichia coli , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidadeRESUMO
In this work, ultrahigh-performance single-walled carbon nanotube (SWCNT)/Se nanowire (NW)/poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) ternary thermoelectric (TE) nanocomposite films are successfully designed by rational design of CNT/Se/PEDOT:PSS ternary nanocomposites. The addition of CNTs apparently improves the electrical conductivity of composite films, resulting in a relatively huge growth of the power factor. The PEDOT:PSS interface layers uniformly attach on both sides of the Se NWs and CNTs effectively, forming a tightly interleaving and interconnected three-dimensional network. As a consequence, a maximum power factor of 863.83 µW/(m·K2) has been achieved for the sample containing 26 wt % CNTs at 434 K. Ultimately, a flexible TE generator prototype consisting of 5-unit freestanding composite film strips is fabricated using the optimized composite films, which can generate a maximum output power of 206.8 nW at a temperature gradient of 44.7 K. Therefore, the present work has a further potential to be used for the flexible polymer/carbon TE nanocomposite films and devices.
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The Z-scheme photocatalytic system provides a promising way to achieve significant photodegradation efficiency. The work embodied here describes the synthesis of highly efficient double Z-scheme g-C3N4/AgI/ß-AgVO3 (g-CNAB) ternary nanocomposite using a one-pot hydrothermal route. The optical properties, phase structure, and morphology of the synthesized samples were investigated using UV-visible diffuse-reflectance spectroscopy (UV-Vis DRS), X-ray diffraction, and scanning electron microscopy, respectively. The transmission electron microscopy investigation revealed that synthesized composite material represents close interfacial interactions. X-ray photoelectron spectroscopy analysis confirms the presence of all the elements in the synthesized ternary nanocomposite materials. The photocatalytic performance of as-prepared photocatalysts has been systematically investigated using the photodegradation of a variety of pollutants, including Rhodamine B, Ciprofloxacin, and 1,5-diphenylcarbazide-Cr(VI) [DPC-Cr(VI)] complex under visible-light irradiation. Among all synthesized materials, such as g-C3N4, AgI, ß-AgVO3, and ternary nanocomposites with varying loading of ß-AgVO3 [g-CNAB(0.5, 1.0, 1.5, 2.0)], the photocatalyst g-CNAB(1.5) nanocomposite achieved a remarkably high photocatalytic efficiency. The quenching impact of several scavengers revealed that reactive species such as superoxide anion radical (O2·-) and hydroxyl radical (·OH) are significant in the degradation of various contaminants. Based on the characterization and application, a plausible photocatalytic mechanism has been sketched out to determine the reaction pathways involved in the degradation of pollutants present in the aqueous medium.