Degradation Of Congo Red Dye Research Articles

Green Synthesis of Silver Nanoparticles Using Aqueous Extract of Rosa brunonii Lindl and Their Morphological, Biological and Photocatalytic Characterizations

In this work, silver (Ag) nanoparticles were synthesized by simple, eco-friendly chemical reaction using aqueous extract of Rosa brunonii Lindl as a reducing agent. The characterizations using scanning electron microscopy, X-ray diffraction (XRD), energy dispersive spectrometry, UV–Vis spectrum and photo luminance spectroscopy confirmed the successful synthesis of Ag nanoparticles. The suitable antioxidant properties of as-synthesized silver nanoparticles using three assays; DPPH, FRAP and ferrous chelation potential, were confirmed. Various in vitro biological parameters of biosynthesized nanoparticles suggested an excellent antimicrobial activity against different (five bacterial and four fungal) microbial strains viz. Escherichia coli, Kleibsella pnemoniae, Campylobacter jejunii, Bacillus cereus, Alcaligenes denitrificans, Bipolaris specifera, Fusarium oxysporum, Aspergillus niger and Curvularia lunata. The as-synthesized silver nanoparticles were found most susceptible to C. jejunii (bacteria) at 47.11 µg/mL and A. niger (fungal) at 70.9 µg/mL. Further, photocatalytic property of silver nanoparticles showed a gradual increase of degradation (%) of Congo red dye under direct sunlight with respect to time for 3 h in the interval of 1 h each. The results confirmed that green synthesized silver nanoparticles are highly efficient for the photocatalytic degradation of the Congo red dye.

Congo red photomineralization over Co3O4/CoTe common cation nanocomposites

Due to increasing energy demands and environmental pollution, it is need of the hour to develop some eco-friendly technologies that can overcome these two major issues. Nanotechnology and photocatalysis provide the best solution for the energy crisis and environmental pollution. Here, in this work, we report metal oxide (Co3O4), metal chalcogenide (CoTe) and their nanocomposites (Co3O4/CoTe) to benefit from synergy attributed to their unique electronic properties for the photocatalytic degradation of Congo red dye, which is a major industrial pollutant. The hydrothermally synthesized photocatalysts are further characterized via various techniques including powder X-ray diffraction, scanning electron microscopy coupled with energy dispersive X-ray spectroscopy and UV–Visible diffused reflectance spectroscopy (DRS) which endorse their successful synthesis. Amongst the as-synthesized photocatalysts, the nanocomposites exhibited better photocatalytic activity as compared to their individual counterparts which is hereby attributed to reduced charge recombination, suitable band alignment in the heterostructure as well as to the presence of common cation.

Synthesis of ZnO nanoparticles by co-precipitation method for solar driven photodegradation of Congo red dye at different pH

Solar driven photocatalytic processes to remove organic pollutants from wastewater and other aqueous solutions is very important and useful due to its environmental benefits regarding sustainability aspect. In this article, we report a study on the use of bare zinc oxide (ZnO) nanoparticles (NPs) prepared by the chemical low temperature co-precipitation method and used as a catalyst to degrade the Congo red dye from aqueous solution using solar radiation. We performed the photocatalytic experiments for degradation of Congo red dye under solar radiation at different pH values. The results showed that the ZnO NPs are effective under solar radiation for degradation of Congo red dye. Even when the pH was varied down to 4 or raised to 10, the degradation was observed to be slightly improved. This result is due to the excess of radicals species, which enhance the photocatalytic process. In general, the observed degradation efficiency of the ZnO NPs is due to the deep level defects within the band gap that were introduced during the growth process of the ZnO NPs, which enhance the absorption wavelength band towards the visible light region. Recycling of the ZnO NPs for 3 successive runs have indicated the feasibility of reusing the NPs for several times. This implies that by using bare ZnO NPs an efficient approach for degradation of toxic waste can be achieved. Radical scavengers were used to evaluate the role of the radicals in the reaction mechanism.

Photodegradation of organic dyes and industrial wastewater in the presence of layer-type perovskite materials under visible light irradiation

Layer-type perovskite materials based on AIAIITi2O6 (AI = Na or Ag or Cu and AII = La) system for the degradation of several organic dyes and industrial wastewater under visible-light irradiation are reported. The known perovskite material NaLaTi2O6 (NLTO) was prepared by a new sol-gel process. Ion-exchange of Na+ ions in NLTO with Ag+ or Cu2+ ion led to new perovskite AgLaTi2O6 (ALTO) and Cu0.5LaTi2O6 (CLTO) respectively. All the new materials were thoroughly characterized by using PXRD, FESEM, HRTEM, UV–vis DRS, IR, XPS and Solid State Photo-luminescence techniques. The new series of materials were utilized for the degradation of Congo Red dye, 4-chlorophenol and 4,4′-bis(2-sulfostyryl)biphenyl as reference pollutants, as well as industrial wastewater. The mineralization process of Congo Red was evaluated through mass spectrometry, which showed that after 60 min of irradiation, the dye degraded with all fragments disappeared. Degradation and mineralization of industrial wastewater was studied by using a newly designed photoreactor via a two-stage process. Mechanistic studies for the fast degradation of Congo Red and industrial wastewater were carried out in the presence of various scavengers. Finally, the photomineralized wastewater was evaluated by chemical oxygen demand (COD) test and the obtained value is close to the standard value. Highest efficiency of degradation was found for ALTO as the photocatalyst, followed by CLTO and then NLTO.

Tuning the band gap of TiO2 by tungsten doping for efficient UV and visible photodegradation of Congo red dye

Tungsten-doped TiO2 (W@TiO2) nanoparticles, with different percentages of atomic tungsten dopant levels (range of 0 to 6 mol%) have been synthesized by the sol-gel method and characterized by UV–Visible spectroscopy, XRD, SEM, EDX, ICP-OES and XPS analysis. By means of UV–Vis spectroscopy, it has been observed that with 6 mol% tungsten doping the wavelength range of excitation of TiO2 has extended to the visible portion of spectrum. Therefore, we evaluated the photocatalytic activity of W@TiO2 catalysts for the degradation of Congo red dye under varying experimental parameters such as dopant concentration, catalyst dosage, dye concentrations and pH. Moreover, 6 mol% W@TiO2 catalyst was deposited on a glass substrate to form thin film using spin coating technique in order to make the photocatalyst effortlessly reusable with approximately same efficiency. The results compared with standard titania, Degussa P25 both in UV- and visible light, suggest that 6 mol% W@TiO2 can be a cost-effective choice for visible light induced photocatalytic degradation of Congo red dye.

Microwave-assisted synthesis of single-walled carbon nanotube-supported ruthenium nanoparticles for the catalytic degradation of Congo red dye

In this article, we describe a rapid, convenient, one-pot microwave method to synthesize Ru nanoparticles supported onto un-functionalized single-walled carbon nanotubes (SWNTs). Depending on the reaction temperature, small ruthenium nanoparticles, of 2.0 ± 0.5 nm or 3.5 ± 0.5 nm, were evenly distributed and stabilized onto SWNTs support without agglomeration. The structural integrity of the carbon nanotube was maintained upon microwave irradiation. The structural morphology of the SWNT-Ru nanoparticle composites was analyzed by high-resolution transmission electron microscopy (HR-TEM), UV-Visible spectroscopy and Raman spectroscopy. The SWNT-Ru nanoparticle composites demonstrated excellent catalytic properties in the decolorization and the degradation of Congo red dye within minutes at ambient temperature and without additional perturbation. The support of the SWNTs played a critical role not only in the synthesis of the non-agglomerated Ru nanoparticles but also in the efficient degradation of the Congo red dye. In addition, the effective recoverability and reusability of the catalyst establish its potential for practical catalytic applications.

Visible light irradiated photocatalytic and magnetic properties of Fe-doped SnS2 nanopowders

Fe-doped SnS2 (SnS2:Fe) nanopowders were synthesized by cost effective chemical method and characterized by thermo gravimetric-differential thermal analysis, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and vibrating sample magnetometer techniques. The photocatalytic activity was evaluated for the degradation of congo red dye under visible light irradiation. XRD studies indicate that both the undoped and doped SnS2 nanopowders exhibit hexagonal crystal structure with a strong (1 0 1) preferential growth. Nanosized grains are evinced from the TEM images. XPS spectra confirmed the presence of Fe in the doped samples. Photodegradation efficiency increased with increase in Fe doping concentration and the SnS2:Fe nanopowder with 10 wt% Fe doping concentration exhibits a maximum efficiency of 93.94% after 180 min light irradiation. Ferromagnetic ordering of pure SnS2 improved with Fe doping. The outcome of the results indicated that Fe-doped SnS2 nanopowders are well suited as diluted magnetic semiconductor and also can be used as an efficient photocatalyst.

Photocatalytic and antibacterial activity of bismuth and copper co-doped cobalt ferrite nanoparticles

Herein we reported the photocatalytic and antibacterial activity of CoFe2O4, CoFe1.9Bi0.1O4 and Cu0.5Co0.5Fe1.9Bi0.1O4 nanoparticles obtained by solution combustion technique using glycine as a fuel. The obtained nanoparticles were analyzed by various techniques such as powder XRD, FTIR, UV-DRS and SEM-EDAX. The band gap value of CoFe2O4 nanoparticle is decreases gradually from 1.46 to 1.00 eV (CoFe1.9Bi0.1O4) and 0.85 eV (Cu0.5Co0.5Fe1.9Bi0.1O4) due to the doping of copper and bismuth. The photocatalytic activity of synthesized nanoparticles was evaluated for the degradation of congo red dye. 89 and 87% removal efficiency of congo red dye was achieved in 90 min under different light (UV and visible light) illumination utilizing 10 mg of Cu0.5Co0.5Fe1.9Bi0.1O4 catalyst. Antibacterial activity of the compounds was tested against two organisms Staphylococcus aureus and Escherichia coli by well diffusion method. Co-doping of copper and bismuth improved the antibacterial activity against the organisms S. aureus (29 mm) and E. coli (34 mm) when compared to cobalt ferrite.

BiOCl-Ag8SnS6 heterostructure: Facile preparation and photocatalytic applications

BiOCl-Ag8SnS6 heterostructured nanocomposites have been synthesized by chemical coprecipitation method in presence of ethylene glycol solvent and capping agent at a moderate temperature (100 °C, 4 h). The BiOCl-Ag8SnS6 heterostructures were characterized by X-ray diffraction, transmission electron microscopy, UV–vis NIR spectroscopy and Brunauer–Emmett–Teller (BET) surface area measurement. XRD pattern of BiOCl-Ag8SnS6 heterostructure showed the peaks corresponding to orthorhombic structure of Ag8SnS6 nanoparticles and tetragonal structure of BiOCl indicating that they exist in biphasic form. BET surface area of BiOCl microspheres, Ag8SnS6 nanoparticles and BiOCl-Ag8SnS6-2 were found to be 1.91 m2/g, 2.35 m2/g and 4.52 m2/g, respectively. BiOCl-Ag8SnS6 heterostructured composites exhibited robust photocatalytic degradation towards degradation of congo red dye than that of single phase BiOCl and Ag8SnS6 nanoparticles under sunlight irradiation. This could be ascribed to heterostructure effect between BiOCl and Ag8SnS6 nanoparticles which facilitate the separation and easy transfer of photogenerated electrons and holes, across the BiOCl-Ag8SnS6 interface resulting into an enhanced photocatalytic activity. The results of different scavengers confirm that photogenerated holes and superoxide radicals was the main active species for oxidising congo red dye during the photocatalytic process.

Biosynthesis of the Fe3O4 Nanoparticles Using Acacia Nilotica Leaf Extract and their Effect on Degradation of Congo Red Dye in Aqueous Solution

Trends in Textile Engineering & Fashion Technology Biosynthesis of the Fe3O4 Nanoparticles Using Acacia Nilotica Leaf Extract and their Effect on Degradation of Congo Red Dye in Aqueous Solution Cheera Prasad K, Sreenivasulu V, Govinda S, Himageerish kumar K, Deepa T, Vasantha Jyothi NVV* and Venkateswarlu P* Department of Chemistry, Sri Venkateswara University, India *Corresponding author: Venkateswarlu P and Vasantha Jyothi NVV, Biopolymers and Thermo Physical Laboratories, Department of Chemistry, Sri Venkateswara University, Tirupati 517 502, Andhra Pradesh, India Submission: February 02, 2018; Published: February 16, 2018 DOI: 10.31031/TTEFT.2018.01.000513 ISSN: 2578-0271 Volume1 Issue3

Studies on Nano-Engineered TiO2 Photo Catalyst for Effective Degradation of Dye

All Heterogeneous photo catalysis employing efficient photo-catalyst is the advanced dye degradation technology for the purification of textile effluent. The present work focuses on Congo red dye degradation employing synthesized Ag doped TiO2 nanoparticles as photocatalyst which is characterized using SEM, XRD and FTIR. Studies are conducted to study the effect of various parameters such as initial dye concentration, catalyst loading and pH of solution. Ag Doped TiO2 photocatalyst improve the efficacy of TiO2 by reducing high band gap and electron hole recombination of TiO2. The reaction kinetics is analyzed and the process is found to follow pseudo first order kinetics.

Photocatalytic degradation of Congo red dye based on titanium dioxide using solar and UV lamp

The textile industries produce large volume of wastewater and contain chemical associated with the dyeing process. Photocatalytic degradation by using TiO 2 as catalyst is proven efficient to degrade the dye. This study was designed to evaluate the effectiveness of degradation toward Congo red dye using TiO 2 as a catalyst in different treatment using solar and UV light. The result shows that the presence of catalysts and high UV radiation will enhanced the percentage degradation of dye. The percent degradation under UV lamp with absence of TiO 2 was 31.72% and with presence of TiO 2 was 66.99%. When treated under direct sunlight, with absence of TiO 2 was 8.09% and with presence of TiO 2 was 64.72%. On different pH value of the dye, the percentage degradation of the dye will decrease in both acidic and alkaline condition. Keywords: photocatalytic degradation; Congo red dye; TiO 2 ; catalyst; solar; UV lamp

A Simple Study on the Photocatalytic Efficiency of Copper Magnesium Ferrite

Nanostructured Materials have great scope in research due to their broad range of applications. Here in this study we have prepared copper doped magnesium ferrite (CuMgFe2O4)through Solution Combustion technique at very low temperature. The synthesized samples were analyzed by powder X-ray Diffraction (XRD) and Scanning Electron Microscope(SEM). The flake like morphology of CuMgFe2O4 catalyst could be clearly identified from the SEM images. The efficiency of CuMgFe2O4 catalyst over Congo Red dye degradation under sunlight were studied and were found to be better than commercial photocatalyst. To further improve the degradation efficiency of the catalyst various parameters was optimized such as H2O2, pH and Catalyst weight. From our studies we confirm that the CuMgFe2O4 catalyst could be a promising material for practical application.

Multi-applicative tetragonal TiO2/SnO2 nanocomposites for photocatalysis and gas sensing

TiO2-based mixed metal oxide heteronanostructures have multiple applications in photocatalysis and gas sensing because of their charge transport properties. In this study, we prepared tetragonal TiO2/SnO2 nanocomposites (NCs) with different weight percentages using a simple wet impregnation method. The physicochemical properties of the NCs were investigated using X-ray diffraction, Fourier transform-infrared spectroscopy, ultraviolet–visible spectroscopy, field-emission scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, and Brunauer–Emmett–Teller surface area analysis. The results showed that the surface area of the NCs increased significantly and the anatase TiO2 was sensitized after the addition of a small amount of cassiterite SnO2 NPs. We systematically studied the as-prepared NCs during the photocatalytic degradation of Congo Red dye under visible light irradiation (λ > 420 nm) and NH3 gas sensing, which demonstrated the efficient photocatalytic performance and the superior sensing response of the catalyst with a weight composition of 25% SnO2 in TiO2 (4:1) compared with the other NCs or the bare individual nanoparticles. The improved photocatalytic and gas sensing performance of the TiO2/SnO2 (4:1) NCs may be attributed to the increased active surface area, the increased adsorption of the dye and target gas molecules, as well as efficient electron–hole charge separation and transfer.

Near room temperature and large-area synthesis of ZnO/Cu2O heterojunction for photocatalytic properties

Large-area ZnO/Cu2O heterojunction have been successfully synthesized on Cu foil through a simple two-step solution method at near room temperature. The field emission scanning electron microscopy characterization indicates that the morphology of as-prepared Cu2O film grown on Cu foil is octahedral structure with diameter of ∼450 nm and ZnO is nanorod arrays structure with diameter of ∼150 nm. The current–voltage measurement of ZnO/Cu2O heterojunction shows a typical rectifying characteristics. Moreover, the photocatalytic test indicates that ZnO/Cu2O heterojunction exhibits high photocatalytic efficient for degradation of congo red dyes. The possible photocatalytic mechanism of ZnO/Cu2O heterojunction is also presented.

Photocatalytic degradation and photo-Fenton oxidation of Congo red dye pollutants in water using natural chromite\u2014response surface optimization

Refined natural Fe-chromite was characterized by XRD, FT-IR, reflected polarized microscope, XRF and UV spectrophotometer. Photocatalytic degradation and photo-Fenton oxidation of Congo red dye by Fe-chromite was investigated using 1 mL H2O2. The degradation of dye was studied as a function of illumination time, chromite mass, initial dye concentration, and pH. Fe-chromite acts as binary oxide system from chromium oxide and ferrous oxide. Thus, it exhibits photocatalytic properties under UV illumination and photo-Fenton oxidation after addition of H2O2. The degradation in the presence of H2O2 reached the equilibrium stage after 8 h (59.4%) but in the absence of H2O2 continued to 12 h (54.6%). Photocatalytic degradation results fitted well with zero, first order and second order kinetic model but it represented by second order rather than by the other models. While the photo-Fenton oxidation show medium fitting with the second order kinetic model only. The values of kinetic rate constants for the photo-Fenton oxidation were greater than those for the photocatalytic degradation. Thus, degradation of Congo red dye using chromite as catalyst is more efficient by photo-Fenton oxidation. Based on the response surface analysis, the predicted optimal conditions for maximum removal of Congo red dye by photocatalytic degradation (100%) were 12 mg/l, 0.14 g, 3, and 11 h for dye concentration, chromite mass, pH, and illumination time, respectively. Moreover, the optimum condition for photo-Fenton oxidation of dye (100%) is 13.5 mg/l, 0.10 g, 4, and 10 h, respectively.

Recycling of glass in synthesis of MCM-48 mesoporous silica as catalyst support for Ni2O3 photocatalyst for Congo red dye removal

Glass was successfully recycled in the synthesis of mesoporous silica MCM-48 which was used as catalyst support for nickel oxide photocatalyst. The resulted products were evaluated using X-ray diffraction, scanning electron microscope and UV–Vis spectrophotometer. The precipitated nickel oxide is of Ni2O3 form and loading of it onto MCM-48 resulted in a reduction in the band gap energy from about 3.66 eV to about 2.4 eV. The role of MCM-48 as catalyst support for Ni2O3 in enhancing the adsorption capacity and photocatalytic properties of nickel oxide was evaluated through series of equilibrium studies and photocatalytic degradation of Congo red dye under visible light. Using of glass-based MCM-48 as catalyst support for Ni2O3 showed enhancing the adsorption capacity by 31.3 and 14.8% higher than the adsorption capacity of Ni2O3 and MCM-48, respectively. Also, the photocatalytic degradation percentage increased by about 67.3% relative to the Ni2O3 degradation percentage. The nature of MCM-48/Ni2O3 adsorption mechanism is chemisorption and occurs in multilayer form throughout the heterogeneous surface of the composite. The using of MCM-48 as support for Ni2O3 photocatalyst enhanced the adsorption capacity through increasing the total surface area. The loading process resulted in fixing of the Ni2O3 particles throughout the porous structure which producing more exposed active photocatalyst sites and active adsorption sites for the incident photons as well as preventing the nickel oxide particles from agglomeration. Based on the obtained results, supporting of Ni2O3 particles onto MCM-48 is promising active centers for the degradation of Congo red dye molecules.

Photocatalytic removal of Congo red dye using MCM-48/Ni2O3 composite synthesized based on silica gel extracted from rice husk ash; fabrication and application

MCM-48 mesoporous silica was successfully synthesized from silica gel extracted from rice husk ash and loaded by nickel oxide (Ni2O3). The resulted composite was characterized using X-ray diffraction, scanning electron microscope, and UV–vis spectrophotometer. The role of MCM-48 as catalyst support in enhancing the photocatalytic properties of nickel oxide was evaluated through the photocatalytic degradation of Congo red dye under visible light source. MCM-48 as catalyst support for Ni2O3 shows considerable enhancement in the adsorption capacity by 17% and 29% higher than the adsorption capacity of MCM-48 and Ni2O3, respectively. Additionally, the photocatalytic degradation percentage increased by about 64% relative to the degradation percentage using Ni2O3 as a single component. The adsorption mechanism of MCM-48/Ni2O3 is chemisorption process of multilayer form. The using of MCM-48 as catalyst support for Ni2O3 enhanced the adsorption capacity and the photocatalytic degradation through increasing the surface area and prevents the nickel oxide particles from agglomeration. This was done through fixing nickel oxide particles throughout the porous structure which providing more exposed active adsorption sites and active photocatalyst sites for the incident photons. Based on the obtained results, supporting of nickel oxide particles onto MCM-48 are promising active centers for the degradation of Congo red dye molecules.

Facile green fabrication of nanostructural Ni-doped ZnO hollow sphere as an advanced photocatalytic material for dye degradation

Through a green protocol, hollow forms of x-Ni-ZnO (x=0, 2, 3, 5, and 10wt% Ni) were prepared in ultrasonic bath at a low temperature using template fructose. For characterizing the shape, structure, crystallite phase, purity, and chemical composition of the prepared hollow spheres, the powder X-ray diffraction (PXRD), Fourier transform infra-red spectroscopy (FT-IR), field-emission scanning electron microscopy (FE-SEM), energy dispersive analysis of X-ray (EDAX), High-resolution transmission electron microscopy (HRTEM), inductively coupled plasma (ICP), and ultraviolet–visible absorption (UV–vis) spectroscopy were employed. Besides, the photo-catalytic properties of these hollow spheres for degrading Congo Red (CR) as an Azo dye were taken into account. According to the results, Ni-ZnO hollow spheres outperform the pure ZnO hollow spheres in terms of the photocatalytic activities. Furthermore, in order to show the impact of various morphologies on the CR dye degradation, the Ni-ZnO nanostructures were produced with rod-like, flower-like, and wood-like morphologies. Our synthesized Ni-ZnO hollow spheres seem to be highly promising for future applications in different commercial fields and industries. Moreover, they are applicable for photodegradation of other organic pollutants.

Sonochemical Synthesis of Mg-TiO 2 nanoparticles for persistent Congo red dye degradation

Abstract In this article, modified TiO2 and Mg-TiO2 nanoparticles was prepared by the facile sonochemical method. The crystal structure evolution and elemental composition were analyzed by X-ray crystallography and X-ray photoelectron spectroscopy. The calculated band gap energy of Mg-TiO2 nanoparticles was lower than that of pure TiO2 −P25. The Fourier Transform Infrared (FT-IR) spectral study established the substitution of Mg2+ on the TiO2 surface. The Raman spectroscopy confirms that the Mg2+ ions were in situ doped on the surface of TiO2 nanoparticles. The photocatalytic efficiency of the synthesized Mg-TiO2-P25 nanoparticles was investigated by performing photocatalytic degradation of persistent Congo red dye under visible light irradiation. It has been found that the Mg-TiO2-P25 nanoparticles possess better catalytic activity than pure TiO2 −P25 and modified TiO2 nanoparticles.