Degradation Of Malachite Green Dye Research Articles

In-grown flower like Al-Li/Th-LDH@CNT nanocomposite for enhanced photocatalytic degradation of MG dye and selective adsorption of Cr (VI)

Inner transition metal ions doped layered double hydroxides–embedded in CNTs have attracted increasing attention for wastewater treatment and renewable energy recently. In this work, the nanostructures of Al-Li/Th-LDH@CNT consisting of flower-like morphology were successfully synthesized by the elegant combination of exfoliated Al-Li/Th LDHs nano-sheets and F-CNTs using the hydrothermal method. The as-synthesized Al-Li@ThLDH-CNT nanocomposite is employed for MG dye photodegradation and selective adsorption of Cr (VI) ions. The Al-Li/Th-LDH@CNT nanocomposite has exhibited excellent visible-light-induced photocatalytic activity towards Malachite green (MG) dye, and almost 98% of (MG) dye is decolorized within 45 min. Studies probing the mechanism demonstrate that the photogenerated hydroxyl radical and holes play a vital role in the MG dye degradation process. Furthermore, the Al-Li/Th-LDH@CNT was tested to examine its selective adsorption behavior towards different metal ions at ultra-low trace levels by the ICP-MS technique. The adsorption behavior of Al-Li/Th-LDH@CNT displayed high removal percentage towards Cr6+ (94.1%), while as 86.7% and 83% for Al-Li and Al-Li-CNT adsorbents and the maximum adsorption capacities of Al-Li, Al-Li-CNT, and Al-Li/Th-LDH@CNT were found to be 156.2, 163.3 and 172.4 mg/g respectively. Thus, preparing layered structure composite using a simple engineered route may open a new strategy to synthesize advanced materials having improved synergistic catalytic properties, which could be effectively used as highly efficient probes for environmental applications.

One-pot synthesis of some new 7‑hydroxy-5-(4-substitutedphenyl)-9-methyl-1,5-dihydro-2H-dipyrimido[1,2-a:4′,5′-d]pyrimidine-2,4(3H)‑dione derivatives and it's optoelectronic, DFT, photocatalytic studies and latent fingerprint applications

Metal-free organic dyes are gaining interest and demands in the field of light absorption and light-emitting applications. In this study, we developed efficient one-pot synthesis of 7‑hydroxy-5-(4-substitutedphenyl)-9-methyl-1,5-dihydro-2H-dipyrimido[1,2-a:4′,5′d]pyrimidine-2,4(3H)‑dione derivatives 4(a-d) using L-proline as a catalyst and structures were confirmed by analytical and spectroscopic techniques. Photophysical properties have been studied in a liquid medium; compounds are absorbed in bathochromic shift at ∼300–500 nm and blue emission at 530 nm, 560 nm, 401 nm and 614 nm, 622 nm respectively. Electrochemical behavior was studied at different scan rates in CH Potentiostat. CV results revealed that all the compounds shows quasi reversible behavior and experimental HOMO-LUMO have been calculated. FMOs, optimized structure and quantum parameters along with UV, FT-IR and COSMO-RS were investigated theoretically. From the theoretical results, compounds are in good agreement with experimental values with better photostability and chemical reactivity. Further, compounds are excellent photocatalysts towards the dye degradation of malachite green dye by reaching 65%, 83%, 87% and 65% respectively. In addition, LFPs images were developed on porous/nonporous materials and visualized under UV light, compounds are excellent adhesion and sensitivity on the porous/nonporous materials. Hence, the obtained compounds can be used as organic electronics application-oriented materials and in forensic Science.

Structural characterization of PVDF/PVA polymer blend film doped with different concentration of NiO NPs for photocatalytic degradation of malachite green dye under visible light

AbstractStructural, optical and photodegradation performance of PVDF/PVA polymer blend doped with different concentration of NiO NPs were studied using casting technique method. The effect of adding NiO NPs on PVDF/PVA are investigated using X‐ray Diffraction (XRD), High Resolution Transmission Electron Microscope (HRTEM), Fourier Transform Infrared–Attenuated Total Reflection (FTIR–ATR), Ultraviolet–Visible Spectroscopy (UV–Vis), and High Resolution Scanning Electron Microscope (HRSEM). XRD results showed that the addition of NiO NPs increase the crystallinity of PVDF/PVA. The appearance and shifting of bands in FTIR–ATR indicate the structural change in the PVDF/PVA with adding NiO NPs combined with decrease in the band gap of nanocomposite films compared to pure blend in UV–Vis confirmed the incorporation of NiO NPs in PVDF/PVA. HRTEM shows the size of NiO NPs ranges from 3 to 10 nm which is agreed with that calculated from Scherrer equation. HRSEM shows a change in surface morphology of nanocomposite sample. Malachite green dye as a textile wastewater pollutant model was chosen to assess the photocatalytic degradation efficiency of PVDF/PVA/NiO NPs. Gradual rising of the weight % of NiO in the prepared films results in higher photocatalytic efficiencies. Photocatalytic activity of PVDF/PVA/7% NiO NPs was 95.4% degradation of malachite green dye at pH 9, 3 g/L film weight and 300 min visible light irradiation. Photocatalytic degradation reaction for malachite green dyes is compatible with Pseudo first‐order kinetic model. Reusability results affirm a low decrease in photocatalytic performance after five runs makes the nanocomposite suitable for applications where reusability is a significant core factor.

Electrospun PVDF/ZnO- Based Composite Fibers for Oil Absorption and Photocatalytic Degradation of Organic Dyes from Waste Water

The one-dimensional PVDF/ZnO composite nanofibers exhibit a large specific area, which is beneficial for the absorption of pollutants in wastewater. Moreover, the uniformly distributed ZnO nanoparticles provide a large number of reaction sites for the degradation of the organic contaminants in wastewater. The prepared multifunctional nanofiber membranes have been exploited to both dye degradation and oil absorption. This multifunctional composite nanofiber membrane are characterized and studied the photocatalytic degradation of organic pollutants. In addition, the oil absorption capacity of PVDF/ZnO composite fibers is examined using engine oil.In this work, a hydrophobic membrane was successfully prepared by incorporating ZnO nanofiller into polyvinylidene fluoride (PVDF) using an electrospinning method (Figure-1) for organic dye degradation and oil absorption applications. The hydrothermal method was used to prepare pure ZnO. The structural properties of PVDF/ZnO composite fibers and pure ZnO were studied using the X-ray diffraction technique (XRD). The crystallite size value for ZnO is calculated using Scherrer’s formula. The calculated crystallite size is 20 nm. The TEM image of pure ZnO shows a flower-like structure. The EDX spectrum shows that the ZnO sample consists of Zn and O elements. SEM images of pure PVDF and PVDF/ZnO composite electrospun mat shows uniformly oriented, interconnected structure with bead free fibers. Finally, the prepared fibers were tested for oil absorption and the photocatalytic degradation of organic dyes. Comparing the oil absorption capacity results of both pure PVDF and PVDF/ZnO, shows that the oil absorption capacity is higher for the composites with the addition of ZnO nanofiller. This is due to the addition of ZnO filler increase the hydrophobicity of the fibers. The superhydrophobic materials can allows oil to flow through and repel water. The photocatalytic activity of PVDF/ZnO was evaluated by the degradation of Azocarmine G (AZG) and Malachite green (MG) dye under sunlight irradiation. The absorption spectra shows the decrease in intensities of the absorption peak of AZG and MG dye upon the increasing of irradiation time. The results showed that 85% of AZG and 90% of MG dye could be degraded within 120 min and 240 min. When the time increases, the photodegradation efficiency also increases for the PVDF/ZnO composite fibers. The results indicate that the PVDF/ZnO composite play an vital role in AZG and MG dye degradation. The smaller crystallite size of ZnO catalyst play a key role in photocatalytic activity. As particle size decreases, the number of active surface sites increases. This in tern enhances the photocatalytic activity. The photocatalytic degradation mechanism of the PVDF/ZnO composite fiber can be explained as follows; When photon energy is irradiated on a ZnO surface, holes and electrons are formed. Superoxide radicals are formed when excited electrons in the conduction band react with adsorbed oxygen, whereas hydroxyl radicals are formed when holes in the valence band react with surface bound water molecules. Both hydroxyl and superoxide radicals have the ability to directly oxidize dye molecules. Good oil absorption efficiency (115 %) was achieved using PVDF/ZnO membrane. The results show that the prepared composite fibers can be used to absorb oil and degrade organic contaminants. This cost-effective, easy operation, reusability, and efficiency of the PVDF/ZnO fiber mats could be potentially useful for water treatment and oil recovery. Figure 1

One pot facile chemical synthesis of Mn doped ZnAl2O4 nanostructured spinel materials for efficient photocatalytic degradation of malachite green dye under visible light irradiation

We report the facile synthesis of Mn doped ZnAl2O4 (MZA) (Zn1- x Mn x Al2O4-δ, where x = 0.0, 0.05, 0.10, 0.15, and 0.20) nanostructured materials by simple chemical precipitation technique. Cubic crystalline structure of the samples was confirmed by XRD. Presence of metal–oxygen (Zn–O) bond in the materials was found out by FTIR analysis. The particle size analysis and SEM confirmed the presence of nanosized grains in the samples. Occurrence of appropriate amount of Zn, Al, O, and Mn was detected by EDAX analysis. The optical characteristics of Zn1- x Mn x Al2O4-δ were studied using UV spectral studies. The band gap of these materials was found to be in the range of 2.65 to 3.001 eV. The photocatalytic degradation of malachite green (MG) dye over Zn1-xMnxAl2O4-δ nanoparticle suspensions in presence of visible light was investigated in aqueous solution. Zn0.8Mn0.2Al2O4-δ could degrade 57% of MG dye after 120 minutes of irradiation at room temperature.

Photocatalytic Degradation of Malachite Green Dye Using Zinc Sulfide Nanostructures

AbstractZinc Sulfide (ZnS) get important attention as a semiconductor photocatalyst among other transition metal sulfides due to its fascinating and extraordinary properties. Here ZnS nanoparticles are synthesized by hydrothermal method using zinc acetate and sodium sulfide as precursors. The structural properties of ZnS was studied by using X‐Ray Diffraction technique (XRD).Exact fitting and crystal information of the sample was obtained from Rietveld refinement with Crystallographic Open Database (COD). It shows that ZnS follows cubic structure without any impurity peaks. Crystallite size and lattice strain values are calculated by using Williamson‐Hall (W−H) Plot method. As temperature increases, the particle size also going to increases due to atomic diffusion phenomena. Tauc plot indicates that the bandgap values decreases with increasing temperature. Accurate determination of bandgap values was analyzed by Boltzmann fitting using sigmoid function. Chemical states of elements were obtained with X‐ray Photoelectron Spectroscopy (XPS).Surface morphology and elemental analysis of ZnS nanoparticles was determined from Field Emission Scanning Electron Spectroscopy (FESEM) and Energy Dispersive spectroscopy (EDS). Then the photocatalytic dye degradation efficiency of synthesized particles for Malachite Green (MG) dye was evaluated. From the studies it was found that ZnS is an efficient photocatalyst and it can be used as a perfect future material to avoid the water pollution.

Influence of Aloe vera and PEG on the evaluation of photocatalytic degradation of MG dye under UV light and visible light irradiation of ZnO nanomaterials

Photocatalytic degradation is an effective method to prevent the environmental pollution caused by organic pollutants. The effect of different combinations on the properties of zinc oxide was studied by preparing polyethylene glycol (PEG) capped ZnO, Aloe vera mediated ZnO, and PEG/Aloe vera combined ZnO via the sol-gel synthesis method. The size and structure of the synthesized samples were confirmed by XRD and SEM analysis. The decrease in bandgap energy value of ZnO/Aloe/PEG than ZnO/Aloe, and ZnO/PEG indicates the easy excitation of electrons in the latter. Here, the photocatalytic degradation of three different ZnO combinations was tested against Malachite Green (MG) dye with twenty minutes of UV light and visible light irradiation time. Furthermore, the photocatalytic degradation efficiency of textile dye wastewater was also evaluated by ZnO/Aloe/PEG combination under both UV light and visible light irradiation. These findings proved the overwhelming photocatalytic degradation of plant extract and surfactant based ZnO, which has been used as effective remediation to treat textile dye effluent.

Photocatalytic degradation of malachite green dye by ZnO and ZnO–β-cyclodextrin nanocomposite

Photocatalytic degradation of malachite green dye by ZnO and ZnO–β-cyclodextrin nanocomposite

Silver-Doped Cadmium Selenide/Graphene Oxide-Filled Cellulose Acetate Nanocomposites for Photocatalytic Degradation of Malachite Green toward Wastewater Treatment.

Silver-doped cadmium selenide/graphene oxide (GO) (Ag-CdSe/GO) nanocomposites have been synthesized, loaded in cellulose acetate (CA) to form Ag-CdSe/GO@CA heterostructure nanofibers, and characterized in terms of structural, morphological, photocatalytic properties, among others. The photocatalytic degradation of malachite green (MG) was estimated using cadmium selenide-filled CA (CdSe@CA), silver-doped cadmium selenide-filled CA (Ag-CdSe@CA), cadmium selenide/GO-filled CA (CdSe/GO@CA), and silver-doped cadmium selenide/GO-filled CA (Ag-CdSe/GO@CA) nanocomposite materials. The Ag-CdSe/GO@CA nanocomposites exhibit and retain an enhanced photocatalytic activity for the degradation of MG dye. This amended performance is associated with the multifunctional supporting impacts of GO, Ag, and CA on the composite structure and properties. The superior photocatalytic activity is related to the fact that both Ag and GO can act as electron acceptors that boost the separation efficiency of photogenerated carriers and the loading of the combined nanocomposite (Ag-CdSe@GO) on CA nanofibers, which can augment the adsorption of electrons and holes and facilitate the movement of carriers. The stability of Ag-CdSe/GO@CA nanocomposite photocatalysts demonstrates suitable results even after five recycles. This study establishes an advanced semiconductor-based hybrid nanocomposite material for efficient photocatalytic degradation of organic dyes.

Green synthesis of Cadmium Sulphide nanoparticles for the photodegradation of Malachite green dye, Sulfisoxazole and removal of bacteria

The development in nanoscience has led to cleaner and safer semiconductor materials that can be used for degrading toxic and resistant pollutants in water. Ecological and environmentally friendliness’s are added features that the semiconductor photocatalyst should possess and these are incorporated via green synthetic approaches. Hence, in this study, Sutherlandia frutescence (S. frutescens), leaf extract was used during the synthesis of Cadmium Sulphide (CdS) nanostructures, as a reducing and stabilising agent. Their morphological analysis revealed the presence of spherical particles. Structural analysis by XRD confirmed the presence of hexagonal S. frutescens CdS nanostructures. Furthermore, through FTIR, the deposition of the phytochemicals on the S. frutescens CdS was confirmed. The S. frutescens CdS nanostructures exhibited a bandgap of 3.55 eV. Thus, they were further investigated for their degradation of Malachite Green dye and Sulfisoxazole (SIZ) under UV light irradiation. Approximately, 91% photocatalytic efficiency was achieved for MG (dye:10 mg/L, catalyst: 50 mg, pH: 2) and the materials could be recycled up to 3 times without using stability. The photogenerated electrons were the major contributors to the photodegradation. The pharmaceutical pollutant, sulfisoxazole, had a 68% degradation after 120 min. In addition, the antibacterial activity of the S. frutescens CdS gave excellent removal against all the bacterial strains for both the model and real water pollutants. This study has shown that various pollutants can be degraded (MG and SIZ) and removed (bacteria) using the S. frutescens CdS.

Photocatalytic Degradation of Malachite Green Dye from Aqueous Solution Using Environmentally Compatible Ag/ZnO Polymeric Nanofibers.

An efficient, environmentally compatible and highly porous, silver surface-modified photocatalytic zinc oxide/cellulose acetate/ polypyrrole ZnO/CA/Ppy hybrid nanofibers matrix was fabricated using an electrospinning technique. Electrospinning parameters such as solution flow rate, applied voltage and the distance between needles to collector were optimized. The optimum homogenous and uniform ZnO/CA/Ppy polymeric composite nanofiber was fabricated through the dispersion of 0.05% wt ZnO into the dissolved hybrid polymeric solution with an average nanofiber diameter ranged between 125 and 170 nm. The fabricated ZnO-polymeric nanofiber was further surface-immobilized with silver nanoparticles to enhance its photocatalytic activity through the reduction of the nanofiber bandgap. A comparative study between ZnO polymeric nanofiber before and after silver immobilization was investigated using X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and thermal gravimetric analysis (TGA). The photocatalytic degradation efficiency of the two different prepared nanofibers before and after nanosilver immobilization for malachite green (MG) dye was compared against various experimental parameters. The optimum degradation efficiency of nanosilver surface-modified ZnO-polymeric nanofibers was recorded as 93.5% for malachite green dye after 1 h compared with 63% for ZnO-polymeric nanofibers.

Green Synthesis of Carbon Quantum Dots Doped on Nickel Oxide Nanoparticles as Recyclable Visible Light Photocatalysts for Enhanced Degradation of Malachite Green

AbstractIn the present study, carbon quantum dots/nickel oxide composites were successfully synthesized by a simple approach. Carbon quantum dots (CQDs) were prepared via a hydrothermal method from Nigella sativa seeds. Then, CQDs were attached to nickel oxide nanoparticles (NiO) as a new class of photocatalytic materials, which can easily be recycled after photodegradation by applying a magnetic field. Nanocomposites were characterized by X‐ray diffraction (XRD), Fourier‐ transform infrared spectroscopy (FT‐IR), transmission electron microscopy (TEM), UV‐Visible and fluorescence spectroscopy. The photocatalytic activity of the composites was assessed using malachite green (MG) as the target pollutant under visible light irradiation. Our results presented that the powder form of the CQDs/NiO composites exhibited outstanding photocatalytic activity for three cycles and could be well restored through the applied magnetic field after photodegradation. About 98 % degradation of MG dye in the solution was confirmed after 60 min of visible light exposure.

Efficient photocatalytic degradation of Malachite green dye using facilely synthesized cobalt oxide nanomaterials using citric acid and oleic acid

Citric acid and oleic acid modified cobalt oxide nanomaterials successfully fabricated by sol-gel process and used to remove malachite green (MG) by photocatalytic degradation. The synthesized nanomaterials were characterized by powder X-ray diffraction (P-XRD), Scanning electronic microscopy (SEM), Transmission electron microscopy (TEM), UV–Visible spectrophotometer, Fourier transform infrared spectroscopy (FT-IR) and Thermogravimetric Analysis (TGA) in order to investigate their structural, morphological, optical, functional and thermal properties, respectively. The PXRD gave the crystalline nature with average crystallite size of 29 and 42 nm for citric acid and oleic acid modified cobalt oxide nanomaterials, respectively. SEM images indicate layered porous aggregates morphology having higher porosity. Optimum condition for photocatalytic degradation of MG dye were found at pH 6.84, dose 0.5 gL-1 for 1 × 10−5 M concentrated dye. Citric acid modified cobalt oxide catalyst exhibited 91.2% photocatalytic degradation of MG dye while in oleic acid modified sample exhibited 66.6% under simulated light due to greater chelating power of citric acid as compare to oleic acid. Kinetics results for MG dye degradation follow to pseudo-second-order kinetics with rate constants 0.00653, 0.084 and 0.00633 mol−1L1min−1 for CoCA, CoOA and Co NPs, respectively. In addition, possible mechanism for the photodegradation of MG dye is also proposed.

Nickel doped zinc oxide with improved photocatalytic activity for Malachite Green Dye degradation and parameters affecting the degradation

Zn1 − xNixO (x = 0, 0.02, 0.04, 0.06, 0.08, 0.1) was synthesized successfully using chemical co-precipitation method. The structural, morphological and optical properties of the synthesized samples were investigated using XRD (X-ray diffraction), SEM (scanning electron microscope), EDX (energy-dispersive X-ray), TEM (transmission electron microscope), FTIR (Fourier transform infrared) and UV–Vis spectroscopy. The photocatalytic activities of the synthesized samples toward the degradation of Malachite Green (MG) dye under UV light irradiation were studied. Zn0.94Ni0.06O was observed to be the better photocatalyst among the studied samples which degrades 77% of the dye under 4 h of irradiation. The effect of operational parameters such as catalyst dosage, initial dye concentration and pH on the degradation percentage was investigated. An optimum condition was obtained for a catalyst load of 0.10 g/L into 15 ppm dye solution at pH 9 which degrades 76% of the dye under 1hour of UV irradiation. Reusability test of the photocatalyst was also performed to check the stability for long-term application of the samples.

Photocatalytic degradation of malachite green dye using zero valent iron doped polypyrrole

The zero valent iron doped polypyrrole (Ppy/Fe) was synthesized via chemical oxidative polymerization method in diethylene glycol medium for the first time in this study. The characterization of synthesized Ppy and Ppy/Fe composites was realized by using fourier transform infrared spectrometer (FTIR), UV-visible diffuse reflectance spectrometer (DRS), scanning electron microscope (SEM), elemental dispersion X-ray analysis (EDX), four point probe electrical conductivity X-Ray diffraction spectroscopy (XRD) and pH at point of zero charge (pHpzc) methods. These characterizations show that there is an interaction between zero valent iron (Fe0) and Ppy polymer. The photocatalytic activity of synthesized Ppy and Ppy/Fe composite were investigated by degradation of malachite green (MG) dye under UV light irradiation. Ppy/Fe composite was achieved complete degradation within 60 min, which is 5.92 times faster than pure Ppy. The effect of irradiation time, ratio of Ppy and Fe0 in the synthesized composites, photocatalyst amount to photocatalytic efficiency of Ppy/Fe is studied. Also, the photocatalytic stability of Ppy/Fe is investigated under UV light illumination for degradation MG dye.

Effective Heterogeneous Fenton‐Like degradation of Malachite Green Dye Using the Core‐Shell Fe3O4@SiO2Nano‐Catalyst

AbstractIn this study, the application of the core‐shell Fe3O4@SiO2nano‐catalysts for fenton‐like degradation of malachite green dye has been presented. The nano‐catalysts were prepared using a combination of solvothermal and sol‐gel techniques and characterized using XRD, FTIR, SEM/EDX, TEM and VSM techniques. The effects of various reaction parameters on the degradation of malachite green dye using the prepared nano‐catalysts were investigated. The optimal condition for pH, catalyst dosage and H2O2amount were found to be at 6.7, 15 mg and 50 μL, respectively. Under the optimized conditions, a degradation efficiency of 96.18 % for malachite green dye was achieved using the catalyst within 30 minutes at 303 K with a pseudo first order rate constant of 0.1102 min−1. The plausible mechanism for MG degradation was determined to be the combination of adsorption and simultaneous decomposition via formation of hydroxyl radicals. The performance of the nano‐catalyst was compared with other fenton‐like catalysts reported in the literature. Finally, the magnetic properties of the Fe3O4@SiO2catalysts was utilized for its successful recovery and application in multiple degradation cycles.

Applications of artificial neural network and Box-Behnken Design for modelling malachite green dye degradation from textile effluents using TiO2 photocatalyst

Most of the photocatalytic studies for pollutant degradation are based on optimizing a single parameter that results in a non-linear relationship between the overall parameters and the photo-degradation reactions. To address this critical problem, herein, we report the use of Response Surface Methodology based on the Box-Behnken Design (BBD) for modeling the photocatalysis degradation of Malachite Green (MG) dye using nano TiO2 as photocatalyst. The catalyst characterizations are carried out using XRD, SEM, and TEM, indicating that the TiO2 prepared by sol-gel synthesis possesses Anatase phase with particles in the nano regime and porous surface morphology. The optimum operating conditions for degradation of MG was identified by the interactive effects of variable factors such as initial dye concentration 10-30 ppm (x1), catalyst dosage 1-3 mg (x2), contact time 20-60 min (x3) using the Box-Behnken method. Furthermore, the degradation reactions are also evaluated by Artificial Neural Networks (ANN). Their predicted results have been validated by the experimental studies and found to be acceptable. Their optimal results to achieve 90% degradation efficiency at TiO2 nanoparticle dosage (3 mg), reaction time (60 min), and initial dye concentration (20 ppm) have been validated by the experimental studies and found to be acceptable.

Synthesis and application of copper ferrite-graphene oxide nanocomposite photocatalyst for the degradation of malachite green

The magnetic graphene oxide (GO) nanocomposites possess unique physicochemical properties, high surface area, high chemical stability, and the ease with which they can be modified and functionalized. In the present work, a nanocomposite of copper ferrite and GO was synthesized through a facile hydrothermal method and their photocatalytic efficiency with dye removal was studied. X-ray diffraction (XRD) was used to characterize the synthesized nanocomposite. The UV–Vis spectrophotometer was used to compare the photocatalytic efficiency for degradation of malachite green dye by using GO/CuFe2O4 nanocomposite, GO and copper ferrite. GO/CuFe2O4 nanocomposite could be recycled and possessed of magnetic and photocatalytic properties hence it can be developed as an inexpensive and alternative photocatalyst for dye removal from wastewater.

Sonocatalytic Degradation of Malachite Green Dye Using Green Synthesized Copper Oxide Nanoparticles

Copper oxide nanoparticles (CuO NPs) were synthesized by a simple green method using Camellia sinensis (Tea) extract as a reducing agent. The CuO NPs were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Field emission scanning electron microscope (FESEM) with energy dispersive X-ray spectroscopy (EDX), High resolution transmission electron microscope (HRTEM) and Selected area electron diffraction (SAED) techniques. The crystallite size estimated by Scherrer method was 35nm. The maximum absorbance of the CuO NPs was observed at 264 nm. The average particle size from HR-TEM was found to be 40-45nm. In this work we demonstrate the degradation of Malachite Green (MG) in aqueous solutions under sonocatalytic treatment. The dissimilarity of dye absorbance under UV-Vis spectrophotometer was used to calculate the degradation efficiency of CuO NPs. Moreover the kinetic process from the degradation result shows the MG dye follows the pseudo-first order kinetics.

Green synthesis of silver nanoparticles, characterization and evaluation of their photocatalytic dye degradation activity

In the present study, silver nanoparticles were synthesized by Citrus reticulata Blanco (Kinnow mandarin hybrid) peel extract. The formation of silver nanoparticles was observed by color change from pale yellow to brown and then confirmed by UV spectral analysis, which showed a peak at 423 ​nm. The silver nanoparticles were found to be spherical and appeared to form nanoclusters as confirmed by TEM and FE-SEM respectively. FTIR analysis was conducted to identify the functional groups present in nanoparticles. Several peaks were observed in the range 525–3251 ​cm⁻1. The major peak observed at 1641.8 ​cm⁻1 exhibit C–N and C–C stretching. The band at 3251.0 ​cm−1 was observed due to stretching vibrations of O–H groups in water, alcohol and phenols. The biosynthesized silver nanoparticles were used for the degradation of malachite green dye, which is harmful for both aquatic and human life. Complete degradation of MG dye was observed after 120 ​h (5 days) of incubation in the presence of sunlight. The results of photo catalytic degradation of malachite green by using nanoparticles demonstrated the feasibility of nanoparticles in purification of water.