Photodegradation Of Malachite Green Dye Research Articles

Efficient visible light-driven Photodegradation of malachite green dye using carbon quantum dots-MXene nanocomposite: Synthesis, characterization, and performance evaluation

BackgroundRemoval of azo dyes is one of important issue in water treatment studies and many of research works focused on it. Current work represents a simple and economical feasible to synthesize carbon quantum dots (CQDs) integrated with Ti3C2(OH)2 MXene nanocomposite (CQDs/MXene) for rapid photodegradation of Malachite green (MG) under visible light irradiation. In practice, CQDs were synthesized via a hydrothermal method from Petroselinum crispum leaves, while Ti3C2(OH)2 nanosheets resulted from a simple etching process of Ti3AlC2 using an alkaline solution (KOH with a trace amount of water). MethodsSubsequently, nanocomposites (CQDs/MXene) were prepared by a self-assembly process through sonication-assisted mixing process under ambient conditions. The prepared catalysts were characterized using various analyses like analysis employing field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), and an energy dispersion X-ray (EDX) spectrometer to determine the chemical composition. The optimum measurement of this activity of the CQDs/MXene was attained through adjusting several constraints such as pH, dye concentration, amount of temperature and photocatalyst. Significant findingsThe kinetics of the degradation process were represented using the Langmuir–Hinshelwood model, with a rate constant (k) of 0.1382 min−1. This means that the degradation of MG dye follows a first-order reaction with respect to the dye concentration. In addition, the study also looked at the reusability of the prepared CQDs/MXene nanophotocatalyst and found that it exhibited outstanding stability after three reaction cycles. This suggests that the nanophotocatalyst is a promising material for efficient and sustainable degradation of MG dye. The nanocomposite displays high photocatalytic activity with the ability to reduce 96.1 % of the MG dye concentration after being exposed to 25 min of visible light.

Study of ZnO nanoparticle-supported clay minerals for electrochemical sensors, photocatalysis, and antioxidant applications

In view of the current study's demonstration of the synthesis of clay-doped ZnO composites, we present a low-cost method for producing clay-metal oxide (clay/ZnO). Utilizing the solution combustion technique, a composite of clay/ZnO was produced utilizing citric acid as both a fuel and a complexing agent. The hexagonal unit cell structure of the created clay/ZnO may be seen using XRD patterns. The ZnO-infused clay was visible in FE-SEM micrographs as homogenous, sphere-shaped ZnO. The possible involvement of clay/ZnO photocatalytic activity in the UV-induced photodegradation of malachite green dye was investigated. The 90% degradation rate shows the composite's outstanding photocatalytic degradation capacity. The resulting substance was electrochemically analyzed using a constructed electrode in 0.1 M KOH electrolyte. It increased its sensor capabilities, which now include chemical and biomolecule sensors, and it excelled in cyclic voltammetry-based redox potential studies. To efficiently evaluate chemically synthesized NPs for electrochemical, sensing, and photocatalytic applications, this study intends to create a solution combustion procedure for the synthesis of clay/ZnO nanocomposite using urea as fuel.

Operational parameters and major active species responsible for the photodegradation of malachite green dye by ZnO/ZnS core–shell nanocomposite photocatalyst

Operational parameters and major active species responsible for the photodegradation of malachite green dye by ZnO/ZnS core–shell nanocomposite photocatalyst

Synthesis of barium oxide nanoparticles and its novel application as a catalyst for the photodegradation of malachite green dye

The synthesis of undoped barium oxide (BaO) and neodymium (Nd)-doped BaO nanoparticles (NPs) was carried out through the co-precipitation technique. The synthesis of cubic structure BaO NPs was confirmed through X-ray diffraction (XRD). The crystallite sizes calculated from X-rays diffractometric (XRD) results for undoped BaO and Nd-doped BaO were 10.50 nm and 10.04 nm, respectively. The morphological study and percent composition of synthesized NPs were investigated using a scanning electron microscope and energy-dispersive X-ray analysis. Thermogravimetric analysis confirmed the decomposition of precursor to BaO after annealing at ~ 500 °C. The band gap energy calculated for undoped BaO was 3.7 eV. The substitution of Nd to BaO decreased this value to 3.4 eV. The activation energy calculated for the doped BaO and undoped BaO was 16.5 kJ/mol and 22.5 kJ/mol, respectively. The Nd-doped BaO degraded about 96.4% dye, while the undoped BaO NPs degraded about 86.6% dye within 120 min. The synthesized BaO NPs were used as novel catalysts for the photodegradation of malachite green (MG) dye by varying irradiation time, catalyst dose, pH, temperatures and dye initial concentration. The maximum degradation efficiency was achieved at pH 4, catalyst dose 10 mg, dye initial concentration 50 ppm, and at a temperature of 50 °C. The dye degradation was also studied using the recovered catalysts.

Facile synthesis of ZnO nanoparticles for the effective photodegradation of malachite green dye in aqueous solution

AbstractZinc oxide (ZnO) nanoparticles were synthesized using a simple co‐precipitation method and applied for effective photodegradation of malachite green (MG) dye in an aqueous solution. The synthesized ZnO nanoparticles were characterized by X‐ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), Fourier transform infrared (FTIR), and ultraviolet–visible (UV–vis) spectroscopic techniques. XRD pattern is confirmed the formation of crystalline ZnO nanoparticles with hexagonal wurtzite structure while the FESEM image validates the preparation of disc‐like spherical nanostructures agglomerated with the size of 30–50 nm. The nanostructures exhibited a strong UV absorption band at 370 nm, and the bandgap energy calculated from the Tauc plot is 3.12 eV. The prepared ZnO nanoparticles exhibited 92.07% photodegradation efficiency against the MG dye in 2 h of UV light irradiation at pH 8. The experimental data has followed the pseudo‐first‐order kinetic model, and the rate constant value obtained is 20.433 × 10−3 min−1. Thus, the synthesized ZnO nanoparticles degraded MG dye effectively and can be utilized for environmental remediation purposes.

UV light illuminated photodegradation of Malachite green dye using ZnO/CuO nanocomposites

The present study involves the successful synthesis of ZnO and ZnO/CuO composites with different compositional ratio 4:1, 3:2, 2:3, 1:1 and 1:4 by hydrothermal method. The synthesized samples were characterized by X-ray diffraction (XRD) technique, UV–Visible and Fourier Transform Infra-Red (FTIR) spectroscopy. The photocatalytic activities of the synthesized samples on the degradation of Malachite green (MG) dye were examined under the illumination of UV light. It was observed that ZnO/CuO composite in the ratio 3:2 showed best activity degrading 82% of MG dye within 4 hrs. of irradiation. The kinetic process of photodegradation was explained by Langmuir-Hinshelwood model and the experimental data was found to be in good agreement with the model predicted. Under optimum condition of catalyst loading 0.2g/L, initial dye concentration of 15ppm and pH-10 of dye solution, complete decolorization of dye was achieved in 2 hrs. The reusability test was conducted to study the stability of photocatalyst under same experimental condition and showed high stability even after four consecutive runs.

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.

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.

Green Synthesis of Biogenic Zinc Oxide Nanoflower as Dual Agent for Photodegradation of an Organic Dye and Tyrosinase Inhibitor

In the study, metabolites of Euphorbia sanguinea were used as benign reducing and stabilizing agents to obtain zinc oxide nanoparticles (ZnO-NPs). The nanoparticles were evaluated as dual agent for photodegradation of Malachite green dye and tyrosinase inhibitior of mushroom tyrosine enzyme. Surface plasmon bands and energy band gaps of the ZnO-NPs were within the range 356–378 nm and 2.72–4.37 eV respectively as obtained from the UV–Vis spectra. SEM/EDS elemental mapping of the nanoparticles gave flower-like shape and even distribution of zinc and oxygen. XRD result revealed crystallographic peaks assigned to hexagonal phase of zinc oxide. The metal oxide nanoparticles were used to achieve 53% percentage degradation of Malachite green dye solution in less than a minute of solar radiation, which increased to 92% in 60 min. A first order kinetics with correlation coefficient R2 of 0.937, rate constant of 0.0084 min−1 and half-life of 82.52 min was established for the photodegradation process. The ZnONPs exhibited good tyrosinase inhibition with IC50 of 49.016 µg/ml. The mode of enzymatic inhibition was competitive with an inhibition constant (Ki) of 0.525 mM using Lineweaver–Burk kinetic model.

Urchin-like CuS nanostructures: simple synthesis and structural optimization with enhanced photocatalytic activity under direct sunlight

Wastewater remediation by nanostructured photocatalysts represents a critical issue for nanotechnology. In this work, we employed a facile, low-cost, and one-pot co-precipitation strategy to synthesize a pure hexagonal phase of copper sulfide (CuS) nanostructures at a relatively lower temperature. The produced CuS investigated using different instrumentation. The results confirmed that CuS crystallized in urchin-like nanostructures with a single hexagonal phase exhibiting a band gap of 2.22 eV. The photocatalytic performance of the prepared CuS examined for the photodegradation of malachite green dye (MG) employing direct sunlight illumination. The outcomes showed that the produced CuS featured photodegradation efficiency of 95.5% and 67.2% mineralization within 90 min. Moreover, the kinetic studies of MG photodegradation and the applicability of CuS photocatalyst displayed a pseudo-first-order reaction with high stability at a decent efficiency. This work opens the door for using only prepared single-phase metal chalcogenides in water remediation under direct sunlight.

Insight into the photocatalytic properties of diatomite@Ni/NiO composite for effective photo-degradation of malachite green dye and photo-reduction of Cr (VI) under visible light

Diatomite frustules decorated by nano Ni/NiO nanoparticles (Diatomite@Ni/NiO) were synthesized as a novel photocatalyst for effective degradation of malachite green cationic dye (M.G) and photocatalytic-reduction of Cr (VI) ions. The composite was characterized by different analytical techniques and revealed enhancing in the surface area (400 m2/g), 5.8 nm as average pore diameter and showed lower band gap energy (1.71 eV) than NiO as single phase. The photocatalytic activity of the composite in the removal of M.G and reduction of Cr (VI) was evaluated under visible light considering the pH, illumination time, catalyst mass, and the pollutants concentrations. The results revealed complete removal of 25 mg/L M.G can be achieved using 20 mg, 30 mg, 40 mg and 50 mg of the after 150 min, 90 min, 60 min, and 30 min, respectively. The complete degradation of 50 mg/L can be obtained after 240 min, 90 min, and 60 min using 20 mg, 40 mg, and 50 mg of the catalyst, respectively. This also was reported for the photocatlytic-reduction of 25 mg/L of Cr(VI) ions as the complete reduction was estimated after 180 min, 60 min and 30 min using 20 mg, 40 mg, and 50 mg, respectively. Also, 50 mg/L of Cr (VI) can be completely reduced after 240 min, 90 min, and 60 min using 20 mg, 40 mg, and 50 mg as catalyst dosage, respectively. The photocatalytic degradation of M.G controlled mainly by the generated electron-hole pairs and the superoxide species while the photocatalytic-reduction of Cr (VI) controlled mainly by the directly excited electrons of Ni/NiO and partially by the formed superoxide radicals. Hence, the synthetic diatomite@Ni/NiO composite can be considered as potential photocatalyst in the degradation of M.G dye and photoreduction of Cr (VI) ions.

Magnetically recoverable Pd-loaded BiFeO3 microcomposite with enhanced visible light photocatalytic performance for pollutant, bacterial and fungal elimination

Herein, magnetically recoverable coral-like Pd-loaded BiFeO3 microcomposites were successfully synthesized using a two-steps hydrothermal technique. The structural, magnetic, optical and textural characteristics of the microcomposite were analyzed by numerous characterization techniques. The Pd nanoparticles loaded on the coral-like BiFeO3 surfaces were quasi-sphere shape with sizes of 15–25 nm. The photodegradation of malachite green dye and phenol were assessed under exposure of visible light to evaluate the catalytic ability of the microcomposite. The findings indicated that Pd-BFO microcomposite exhibited the higher photoactivity than that of pure BFO or commercial TiO2. The enhanced photoactivity was accredited to appropriate Pd content that could improve the light absorbance in the visible region and efficiently improved the photogenerated charge carriers separation/migration abilities as confirmed by the UV-vis diffuse reflectance, photoelectrochemical and photoluminescence analyses. The intermediates formed during the phenol degradation were also detected. The cyclic test showed that the Pd-BFO microcomposite has excellent recyclable ability together with a minimal leakage of palladium ions after six runs. Based on the radical trapping test, hydroxyl radicals, hole and hydrogen peroxide were the chief reactive species contributing to the photodegradation. Furthermore, for the first time, antimicrobial activity towards Escherichia coli, Staphylococcus aureus, Enterococcus faecalis and Aspergillus niger were explored, and the consequence revealed that the Pd-BFO microcomposite presented exceptional antimicrobial properties.

Silver decorated Cu/ZnO photocomposite: efficient green degradation of malachite

Due to their magnificent efficiency to the degradation of hazardous organic pollutants, nanomaterials possessing visible light-driven photocatalytic activity have drawn considerable attention. Herein, Ag decorated Zn0.95Cu0.05O photocomposites have been synthesized via a sol–gel method and characterized as potential photocatalysts for the degradation of malachite green (MG). The formation of the nanocomposites is confirmed by XRD, EDS mapping and TEM analyses. The UV–Vis analysis reveals a gradual decrease in the optical band gap with increasing Ag content, which enhances its visible light absorption and ultimately improves the photocatalytic activity as reflected by the efficient photodegradation of MG dye. Particularly, Zn0.94Cu0.05Ag0.03O exhibits the lowest energy gap and very high photocatalytic activity for the degradation MG. This research demonstrates a new pathway for the preparation of Ag incorporated oxide-based nanostructured composites as promising photocatalysts.

CNT supported Mn-doped ZnO nanoparticles: simple synthesis and improved photocatalytic activity for degradation of malachite green dye under visible light

Hexagonal ZnO nanoparticles doped with Mn and supported with a minor amount of carbon nanotubes (CNTs) were synthesized through a simple coprecipitation-ultrasonication process with high yield. The effect of Mn doping, as well as CNTs addition on structure, surface morphology and texture, optical and electronic properties, was studied. We found that just 1% Mn doping and 1% CNT addition on ZnO showed the best crystallinity, highest surface area, improved visible light absorption, and a lowest estimated band gap of 2.6 eV with minimum charge recombination as revealed from photoluminescence spectra. The application of the optimum composition of the synthesized sample for the photodegradation of malachite green dye showed enhanced photocatalytic activity > 95% under visible light irradiation within 120 min at a minimum dosage of 0.1 g L−1 without any using of hole scavenger or changing the pH. This work highlighting the humble preparation procedure and develops photocatalysis research for real industrial applications.

Visible light photocatalytic activities of BiOBr-activated carbon (derived from waste polyurethane) composites by hydrothermal process

Hybrid materials such as activated carbon based photocatalysts are very promising advanced materials which are bifunctional with both adsorption and photocatalytic properties. In the present work, activated carbon (AC) was prepared from waste polyurethane foam materials. The photocatalytic hybrid materials were synthesized from bismuth oxide precursor (BiOBr) and activated carbon by hydrothermal process. The prepared AC-BiOBr composite was characterized by XRD, FE-SEM, surface area, porosity, zero point charge and UV-DRS. The prepared AC-BiOBr composite had lesser band gap energy (2.64eV) when compared to pristine BiOBr (2.84eV). The photodegradation efficiency of the prepared composite was evaluated for the degradation of malachite green dye under visible light irradiation. Preliminary photocatalytic studies were carried out by varying initial aqueous phase pH, catalyst dosage and initial malachite green dye concentration. Kinetic studies were also carried out for the degradation of malachite green dye by pristine BiOBr and AC-BiOBr composite. The rate constants of the photodegradation were evaluated by fitting the kinetic data with pseudo first-order model equation and the rate constants of AC-BiOBr composite was slightly higher than that of pristine BiOBr. The effect of adsorption on photocatalytic degradation was evaluated by adsorption experiments using AC, BiOBr and AC-BiOBr composite as dark reactions. The equilibrium adsorption data were modelled using Langmuir and Freundlich isotherms. The plausible mechanism for the photodegradation of malachite green dye was also proposed using MALDI-TOF spectral analysis. The prepared adsorbent-photocatalytic composite had good adsorption and photocatalytic degradation efficiency for the removal of malachite green dye molecules from aqueous solution.

Photodegradation of malachite green dye catalyzed by Keggin-type polyoxometalates under visible-light irradiation: Transition metal substituted effects

In the present paper, Keggin-type polyoxometalates (POMs) (NH4)3[PW12O40] and its mono-transition-metal-substituted species (NH4)5[{PW11O39}MII(H2O)] (M = Mn, Fe, Co, Ni, Cu, Zn) have been synthesized and used as photocatalyst to activate O2 for the degradation of dye molecule under visible-light irradiation. Because of the strong adsorption on the surface of POM catalyst, malachite green (MG) molecule was employed as a molecular probe to test their photocatalytic activity. The photodegradation study shows that introduction of transition metal ion leads to an increase in the degradation of MG in the following order: Mn < Fe < Co < [PW12O40]3− < Ni < Cu < Zn, which indicates that the photocatalytic activity of these POMs is sensitive to the transition metal substituted effects. Electronic structure analysis based on the density functional theory calculations shows that a moderate decrease of oxidizing ability of POM catalyst may improve the photocatalytic activity in the degradation of dye molecule under visible-light irradiation. Meanwhile, intermediate products about the photocatalytic oxidation of MG molecule were proposed on the basis of gas chromatograph mass spectrometer analysis.

BaBiO3 Assisted Photodegradation of Malachite Green Dye Under Visible Light Irradiation: Adsorption and Degradation Kinetics

Nano sized BaBiO3 is prepared through Pechini method and characterized by SEM, XRD, FTIR, DT-TGA and UV DRS. The kinetic studies of adsorption and degradation phenomena involved in the photocatalytic degradation of Malachite Green dye using a batch reactor under visible light were investigated. Experiments were performed in a suspended BaBiO3 photocatalyst system. The effect of catalyst loading, solution pH and initial dye concentration on dye degradation is investigated. In addition, adsorption experiment is also performed which indicates that adsorption pattern follows Langmuir model. The decomposition of Malachite Green dye follows pseudo first order kinetics and the Langmuir-Hinshelwood mechanism is found to be valid. Different kinetic parameters for adsorption and photocatalytic degradation of dye are also determined.

Photocatalytic and Fenton-like Photocatalytic Activity of C-doped ZnO Nanoparticles in the Degradation of Malachite Green in a Water

The C-doped ZnO nanoparticles were synthesized by sol-gel method using different amount of propylene glycol as a complexing agent. The propylene glycol led to the doping of C into the nanoparticles, and the C content in the nanoparticles increased as increasing the amount of propylene glycol. The nanoparticles showed excellent photocatalytic activity in photodegradation of malachite green dye in water. The C-doping expanded the light absorption of the nanoparticles to long wavelength and so speeded up the photodegradation of thye dye. Significantly, the nanoparticles also can completely decolorize the malachite green within a short period in the present of hydrogen peroxide, showing remarkable Fenton-like photocatalytic activity. An optimal H2O2 dosage was observed. The Fenton-like reaction was more faster as increasing the C content and decreasing the average particle size of the ZnO nanoparticles. The quasi-kinetic rate constants of the photocatalysis systems are in the range of ~0.0462–0.0700 min-1 and increase to ~0.112–1.498 min-1 by synthetically using H2O2. Keywords: Fenton-like reaction, nanostructure, photocatalysis, semiconductors, ZnO.

Photocatalytic performance of ZnO nanomaterials for self sensitized degradation of malachite green dye under solar light

ZnO nanomaterials of different morphologies are synthesized by different methodologies. These semiconductor photocatalysts are potentially explored for self-sensitized photodegradation of malachite green (MG) dye in water in a batch reactor. The effects of various parameters like initial dye concentration, catalyst loading, solution pH, light source on degradation efficiency was also investigated. The experimental results showed substantial reduction of COD, besides removal of colour. The photodegradation of MG dye followed the pseudo first order kinetics of Langmuir–Hinshelwood model. The hydrothermally synthesized flower shaped homocentric pencil like ZnO nanorod bundles exhibit excellent photocatalytic activity under solar light. A comparative study of photodegradation efficiency among ZnO nanoparticles, ZnO nanoparticles (hydrothermal) and flower shaped homocentric pencil like ZnO nanorod bundles were also performed. Semiconductor photocatalysis often leads to partial or complete mineralization of organic pollutants. The CO2 gas evolved due to mineralization of MG was determined using Warburg manometric method under solar light. The possible mechanism of photodegradation under both solar and UV light were also proposed.

Preparation of CdS Nanoparticles with Reverse Micelle Method and Photo-degradation of Malachite Green Dye

Cadmium sulfide(CdS) nanoparticles with efficient photocatalytic activity were synthesized using wa-ter/CTMAB/n-butyl alcohol/n-heptanes reverse micelle system.The particles exhibited various photocatalytic activi-ties with the different ω values(ω = [Water]/[CTMAB] = 25,35,50),and the optimal ω value was 25.Based on the X-ray diffraction(XRD) and transmission electron microscope(TEM) analysis,CdS nanoparticles were ascribed to the cubic sphalerite and the average size of CdS particle(ω=25) was about merely 9nm.Moreover,the ω values could di-rectly affect the particle size and electrical property of CdS nanoparticles by means of cyclic voltammetry(CV) and electrochemical impedance spectroscopy(EIS).Under visible light(λ≥420nm) irradiation,Malachite Green(MG) was used as a probe to investigate the effect of preparation conditions on photocatalytic activity of CdS nanoparticles.It can be concluded that MG could fade out within 70min and attain the 50% mineralization after 30h under visible light irradiation,and the degradation process mainly referred to the hydroxyl radical(-OH) and H2O2.