Degradation Of Methyl Violet Research Articles

Highly selective functional luminescent sensor toward Cr(VI)/Fe(III) ion and nitrobenzene based on metal–organic frameworks: Synthesis, structures, and properties

Six functional metal-organic frameworks constructed from semi-flexible 4,4′-bis(imidazolyl)diphenyl ether (bidpe), namely: [Zn(bidpe)(mpa)]n (1), [Cu(bidpe)(mpa)(H2O)]n (2), [Cd(bidpe)(mpa)]n (3), [Zn1.5(bidpe)2(smpa)(H2O)]n (4), [Cu1.5(bidpe)2(smpa)(H2O)]n (5), [Cd(bidpe)(hmpa)]n (6) (H2mpa = m-Phthalic acid, H2smpa = 5-sulfonatobenzene-1,3-dicarboxylate, H2hmpa = 5-Hydroxyisophthalic acid), have been synthesized under solvothermal conditions. Single-crystal X-ray diffraction analysis reveals that complexes 1–4 and 6 show 2D→3D supramolecular structure with a Schläfli symbol of (44·62), (4·65), (44·62), (42·6) and (63) topology, respectively. Complex 5 possesses an unprecedented (3, 4, 6)-connected 3D framework with a Schläfli symbol of (4·64·8)2(42·64·89)(62·8)2. Meanwhile, complexes 1, 3, 4 and 6 have excellent fluorescence properties and can be used as potential luminescent sensors for sensing Cr(VI) anions, Fe(III) ions and nitrobenzene (NB) with high selectivity and sensitivity. The photocatalytic studies indicate that 1 has good photocatalytic capability in degradation of methylene blue (MB), 1 and 6 have good photocatalytic capability in degradation of methyl violet (MV). Furthermore, the possible sensing mechanism and photocatalytic mechanism have been discussed.

Fabrication and characterization of novel Fe0@Guar gum-crosslinked-soya lecithin nanocomposite hydrogel for photocatalytic degradation of methyl violet dye

Water pollution is the most threatening issue prevailing in our society these days. Methyl violet is released into the water resources through textile and paint industries. High dye concentration in water inhibits the photosynthesis process thus, affecting the aquatic life. In addition, it indirectly affects the human health also. So for photochemical exclusion of methyl violet from aqueous solution, we have designed zero valent iron @guar gum crosslinked soya lecithin nanocomposite hydrogel (Fe0@GG-cl-SY NCH), synthesized via ultrasonication method. Impregnation of zero valent iron (ZVI) onto the GG-cl-SY was characterized by various modern techniques such as FTIR, XRD, SEM, XPS, TEM and TGA. It was successfully utilized for the photodegradation of methyl violet from aqueous solution. Imprinting of ZVI onto GG-cl-SY and presence of H2O2 greatly enhanced the photodegradation of methyl violet. Neutral pH favoured the maximum methyl violet degradation. 81% degradation of methyl violet was observed within 120 min in the presence of H2O2 and Fe0@GG-cl-SY NCH. Scavenger study showed the reactive degradation species were the hydroxyl radicals which were further confirmed by ESR studies. LC-MS study showed the degradation of methyl violet into smaller fragments followed by complete mineralization.

Structures and photocatalytic performance of two d10 metal-based coordination polymers containing mixed building units

The linker 1,4-bis(2-methyl-imidazole-yl)-butane (bib) was used to construct two coordination polymers, specifically [Cd(bib)(ipa)]n (1) and [Zn(bib)(tpa)]n (2), in the presence of isophthalic acid (H2ipa) and terephthalic acid (H2tpa), respectively, under solvothermal conditions. Topological analyses reveal that the crystal of complex 1 consists of a 3D threefold interpenetrating network with Schlafli symbol {65.8}, while complex 2 possesses a 2D wavelike layer structure with Schlafli symbol {66}. The photocatalytic properties of both complexes for the degradation of methyl violet have been explored, revealing that complex 2 is a better photocatalyst than 1. A mechanism for the photocatalytic properties of the complexes is proposed, based on the results of density of states (DOS) and partial DOS calculations.

A new mixed ligand based Cd(II) 2D coordination polymer with functional sites: Photoluminescence and photocatalytic properties

The solvothermal reaction of Cd(OAc)2·2H2O with 5-(4-carboxyphenoxy)isophthalic acid (H3L) as ligand and 3,3′,5,5′-tetramethyl-4,4′-bipyrazole (bpz) as co-ligand afforded a new coordination polymer [Cd(L)(Hbpz)]n (1), which was characterized. Compound 1 shows 2D layer network which can work as highly sensitive sensor to detect Fe3+ by the decrease in its luminescence intensity because of the existence of active sites. The photocatalytic activity towards the degradation of methyl violet (MV) in polluted water was explored. In addition, the photocatalytic activity of 1 against the photodecomposition of organic dye has been addressed using density of states (DOS) calculations.

Efficacy of photoluminescence and photocatalytic properties of Mn doped ZrO2 nanoparticles by facile precipitation method

Pure ZrO2 and Mn (0.02, 0.04, 0.06, 0.08 M) doped ZrO2 nanoparticles were successfully prepared by chemical precipitation method. The structural, optical, morphological and electronic properties were determined using XRD, UV-DRS, PL, FE-SEM, TEM and XPS techniques. The XRD pattern of pure and Mn doped ZrO2 shows the formation of t-tetragonal phase and shifting of tetragonal phase to monoclinic phase. The energy gap of pure and Mn doped ZrO2 nanoparticles were computed by UV-DRS spectroscopy. The energy gap value of pure and Mn doped ZrO2 nanoparticles decreased from 5.12 to 2.46 eV with increase of manganese concentration. X-ray Photoelectron spectroscopy (XPS) affirmed the presence of Zr4+ and Mn2+ ion in prepared nanoparticles. PL spectra of the pure and Mn doped ZrO2 nanoparticles exhibited oxygen vacancies. The photocatalytic actvity of Mn (0.08 M) doped ZrO2 nanoparticles was successfully sought on photo degradation of Methyl violet and Methylene blue under sunlight irradiation.

DEGRADASI METIL VIOLET MENGGUNAKAN KATALIS ZnO-TiO2 SECARA FOTOSONOLISIS

Research on the degradation of methyl violet has been done by using photosonolysis method. The purpose of this study is to determine how much time the optimum, optimum pH and the amount of doping TiO2 optimum degrade methyl violet as well as the percent degradation, determined the crystal structure and particle size of the catalyst synthesis of ZnO-TiO2 optimum degrade methyl violet using XRD, determine the value of the band gap Of the optimum ZnO-TiO2 catalyst synthesis in degrading methyl violet using UV-DRS, determining the absorption peak of Zn-O-Ti bonds from optimum ZnO-TiO2 catalyst synthesis in degrading methyl violet using FTIR. The results showed that the optimum time to degrade methyl violet was 45 minutes with 94,1371% degradation percentage. For pH variation, the optimum degradation results at pH 6 with percent degradation of 99.2857%. The effect of TiO2 doping variation showed optimum degradation result obtained on doping variation of TiO2 5% with percentage degradation of 96,2500%. The optimum catalyst structure of ZnO-TiO2 catalyst in degrading methyl violet with XRD is wurtzite (anatase) and the particle size is 42.65 - 107.60 nm. The band gap value of the optimum ZnO-TiO2 catalyst in degrading methyl violet with UV-DRS is 3.18 eV. The absorption peak of ZnO-Ti for optimum catalyst ZnO-TiO2 in degrading methyl violet with FTIR is 745.70 cm-1.

Amino acid modified combustion synthesis, characterization and investigation of magnetic, optical and photocatalytic properties of Gd2CoMnO6 nanostructures

Gd2CoMnO6 nanostructures (GCMO NSs) were synthesized through a simple combustion method at 800 °C calcination temperature in the presence of the different amino acids, including phenylalanine, beta-alanine, leucine, valine and glycine, as combustion, gelling and stabilizing agents. In this work, metal nitrate salts were used as starting materials and the Gd:Co:Mn molar ratio was selected to be 2:1:1. The beta-alanine was selected as the optimum amino acid. Effects of type of the amino acid and calcination temperature on the morphology and particle size of the products were investigated. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), ultra violet-diffuse reflectance spectroscopy (UV-DRS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX) and vibrating sample magnetometer (VSM) were used for characterization and investigation of the applications of GCMO NSs. VSM results showed an antiferromagnetic behavior for the GCMO NSs. Optical properties of the NSs were investigated and the optical band gap of them was found to be 3.28 eV. Also photocatalytic properties of the GCMO NSs for the degradation of methyl violet, erythrosine and eriochrome black T were investigated.

Methyl Violet Degradation Using Photocatalytic and Photoelectrocatalytic Processes Over Graphite/PbTiO3 Composite

Photocatalytic and photoelectrocatalytic degradation of methyl violet dye using Graphite/PbTiO3 composites has been conducted. The purposes of this research were to examine photocatalytic and photoelectrocatalytic degradation of methyl violet using Graphite/PbTiO3 composite. Synthesis of Graphite/PbTiO3 composite was successfully performed via sol-gel method by mixing graphite powder, titanium tetra isopropoxide precursor solution (TTIP) and Pb(NO3)2. The Graphite/PbTiO3 composites were characterized using X-Ray Diffraction (XRD), Fourier Transform-Infra Red (FT-IR), and Scanning Electron Microscopy (SEM). The XRD diffractogram and IR spectrum of Graphite/PbTiO3 composite revealed all characteristic peak of graphite and PbTiO3. Photocatalytic degradation process showed that Graphite/PbTiO3 composite with ratio 1/1 decreased concentrations of methyl violet up to 92.20 %. While photoelectrocatalytic degradation processed for 30 minutes at neutral pH and 10 V voltage degraded the methyl violet until 94 %. However, the photoelectrocatalysis is still not significance to improve methyl violet degradation compared with photocatalysis.

Rapid degradative effect of microbially synthesized silver nanoparticles on textile dye in presence of sunlight

Abstract In the study, the dye collected from industry was identified as methyl violet by LC-MS/MS analysis. The biosynthesized silver nanoparticles (AgNPs) used were characterized by UV–visible spectrophotometry, HR-TEM and FT-IR analysis. Further, the AgNPs were used to evaluate the photocatalytic degradation of methyl violet. The results showed rapid degradation (85.56%) of methyl violet within a period of 20 min in presence of AgNPs and sunlight. The superior photocatalytic activity of AgNPs observed in the study indicates its application for dye degradation.

Nanostructured KTaTeO6 and Ag-doped KTaTeO6 Defect Pyrochlores: Promising Photocatalysts for Dye Degradation and Water Splitting

In this study, the nanostructured parent KTaTeO6 (KTTO) and Ag-doped KTaTeO6 (ATTO) catalysts with defect pyrochlore structure were prepared by solid-state and ion-exchange methods, respectively. The synthesized materials were characterized by various techniques to determine their chemical composition, morphology and microstructural features. The XRD studies show that both KTTO and ATTO have cubic structure (space group Fd3m) with high crystallinity. The doping of Ag altered the BET surface area of parent KTTO. The nano nature of the samples was studied by TEM images. A considerable red-shift in the absorption edge is observed for ATTO compared to KTTO. Incorporation of Ag+ in the KTTO lattice is clearly identified from EDX, elemental mapping and XPS results. Degradation of methyl violet and solar water splitting reactions were used to access the photocatalytic activity of KTTO and ATTO. The results obtained suggest that compared to KTTO, the ATTO showed higher photocatalytic activity in both cases. The favourable properties such as high surface area, more surface hydroxyl groups, stronger light absorption in visible region and narrower band gap energy were supposed to be the reasons for the high activity observed in ATTO.

Physical and photo-electrochemical characterization of natural phosphate material. Application to basic dyes photodegradation

Photocatalytic degradation of methyl violet (MV) and rhodamine B (RhB), in single and binary systems, using natural phosphate rock was investigated, motivated by its low cost, abundance, and environmental friendliness. The physical and photo-electrochemical properties of the material were studied. The diffuse reflectance spectrum indicated a direct allowed optical transition at 2.66 eV. The thermal variation of the electrical conductivity showed semiconductor behavior following an exponential type law with low activation energy. Photo-electrochemical studies revealed that the phosphate material exhibited n-type behavior with conduction band of 0.16 VRHE and valence band of 2.82 VRHE, permitting production of both $${\text{O}}_{2}^{ \cdot - }$$ and HO· oxidizing radicals, respectively, responsible of photodegradation of MV and RhB. In single solutions, both dyes were degraded under ultraviolet (UV) light, within 240 min for MV and 330 min for RhB. However, in binary systems, degradation of RhB was effective only when most of the MV had disappeared. Photocatalytic degradation of MV and RhB on natural phosphate.

Fluorescence sensing and photocatalytic properties of a 2D stable and biocompatible Zn(II)-based polymer

A biocompatible metal-organic framework (MOF) [Zn2(TPL)(FA)(OH)(H2O)] (1) (TPL = theophylline and H2FA = fumaric acid) had been chosen which offers an ideal model for the development of fluorescencent chemosensor using simple synthetic protocol. The MOF 1 have been tested as a fluorescent chemosensor against nitro-aromatics (NACs) and it displayed high selectivity for 4-NT over other NACs as evident by the emission spectroscopy. The alleviation in fluorescence intensity of 1 in presence of different NACs have been explained with the help of theoretical calculations which suggested that there is occurrence of both electron and energy transfer processes, in addition to electrostatic interaction between 1 and NACs which may be responsible for the unprecedented selective alleviation in the fluorescence intensity. Also, 1 had been deployed as a photocatalyst for the degradation of methyl violet (MV) and Rhodamine B (Rh B) in aqueous solution under UV irradiation. The photocatalytic results indicated the 1 exhibit 85% photocatalytic efficiency against Rh B in 100 min, while its efficiency against MV was only 50% under the identical experimental conditions. The possible mechanism for the photocatalytic activity has been proposed using density of states (DOS) calculations.

A porous zinc(II) metal–organic framework exhibiting high sensing ability for ferric and nitroaromatics as well as photocatalytic degradation activities against organic dyes

A NbO-type Zn(II) metal–organic framework of {[Zn2(HL)(H2O)2]∙H2O}n (1) has been developed using a pentacarboxylate 2,5-bis(3′,5′-dicarboxylphenyl)-benzoic acid (H5L) ligand and characterized. The single-crystal X-ray diffraction studies indicate that 1 comprises free –COOH groups and Zn(II) centers bridged by four carboxylate groups to form a paddle wheel SBU which is further connected by L5− ligands to build a 3-D porous network with two types of cages. The chemically stable MOF 1 behaves as a highly selective and sensitive fluorescent chemosensor for the detection of Fe3+ ions, 2,4,6-trinitrophenol (TNP), which is known to be an extremely hazardous and strong explosive. Furthermore, the photocatalytic properties of 1 for degradation of methyl violet (MV) and Rhodamine B (RhB) have been explored. The possible emission quenching mechanism in the presence of nitro-aromatics (NACs) has been addressed by theoretical calculations and photocatalytic activity of 1 against organic dyes has been supported using density of states (DOS) calculations.

One-pot synthesis and improved photocatalytic performance of Ag10Si4O13/N–CeO2 composites

Novel Ag10Si4O13/N–CeO2 composite photocatalysts were synthesized by a facile one-pot method. XRD, SEM, EDS, and UV–Vis DRS were employed to characterize the structures of the samples. Moreover, the degradation activity of methyl violet (MV) was used to measure the photocatalytic performances of Ag10Si4O13, N–CeO2, and the Ag10Si4O13/N–CeO2 composites. It was found that ASO-10 (the Ag10Si4O13/N–CeO2 composite with 10 mg N–CeO2) showed the highest photocatalytic activity in the degradation of MV, and the enhanced photocatalytic performance is attributed to an improvement in the separation efficiency of photoproduced electron–hole pairs. Effects of operational parameters, such as initial pH, catalyst dosage, initial dye concentration, anions and cations, have also been considered for better practical applications. In addition, the photocatalytic mechanism of the Ag10Si4O13/N–CeO2 composites is also proposed.

Efficient photocatalytic degradation of methyl violet with two metall–organic frameworks

Two metal–organic frameworks, [Co2(L)(H2O)2(4,4′-bipy)]·3CH3CN (1) and [Mn2(L)(1,10-phen)(H2O)]·H2O (2) (H4L = 5-[bis(4-carboxybenzyl)-amino]isophthalic acid; 4,4′-bipy = 4,4′-bipyridine, 1,10-phen = 1,10-phenanthroline), with two different N-donor ligands have been synthesized. The structures of both MOFs were determined using single-crystal X-ray diffraction technique. MOF 1 shows 3D uncommon (4,6,6)-c net with (4.53.62)2(57.66.82)(42.54.66.72.8) topology while in the case of 2, only L4− ligands link Mn(II) ions into a 2D layer structure with chelating 1,10-phen ligand. The results demonstrate that variation in the N-donor ligands plays a pivotal role in deciding the framework of the two MOFs. Both MOFs have been exploited as photocatalyst materials for the degradation of MV. The photocatalysis results indicate that the two MOFs are stable and are prospective candidates for degradation of methyl violet under UV light irradiation. Additionally, 2 displayed superior photocatalytic activity in comparison to 1. The probable photocatalytic activity mechanism for both 1 and 2 against MV has been proposed using density of states (DOS) calculations.

Photocatalytic and Photoelectrocatalytic Degradation of Methyl Violet Using Graphite/PbTiO3 Composite

Photocatalytic and photoelectrocatalytic degradation of Methyl Violet dye using Graphite/PbTiO 3 composites has been conducted. The purposes of this research were to synthesis the Graphite/PbTiO 3 composite electrode and determine its effectiveness on Methyl Violet degradation. Synthesis of Graphite/PbTiO 3 composite was successfully performed via sol-gel method by mixing graphite powder, titanium tetra isopropoxide precursor solution (TTIP) and Pb(NO 3 ) 2 . The Graphite/PbTiO 3 composites were characterized using X-Ray Diffraction (XRD), Fourier Transform-Infra Red (FT-IR) and Scanning Electron Microscopy (SEM). The XRD diffractogram and IR spectrum of Graphite/PbTiO 3 composite revealed all characteristic peak of graphite and PbTiO 3 . Photocatalytic degradation process showed that Graphite/PbTiO 3 composite decreased concentrations of Methyl Violet up to 92.20%. While photoelectrocatalytic degradation processed for 30 minutes at neutral pH and 10 V voltage degraded the Methyl Violet until 94%.

Photocatalytic degradation of organic dyes by a stable and biocompatible Zn(II) MOF having ferulic acid: Experimental findings and theoretical correlation

The photocatalytic properties of d10-based metal-organic frameworks (MOFs) have been developed as a potential technology in the photo-degradation of organic dyes. Herein, a biocompatible metal-organic framework (MOF) {[Zn2(fer)2]∙0.5H2O}n (1) (fer = ferulic acid) has been selected which shows photocatalytic activity for the degradation of methyl violet (MV) and Rhodamine B (Rh B) in aqueous solution under UV irradiation. The photocatalytic results indicated the 1 exhibit 88% photocatalytic efficiency against Rh B in 100 min, while its against MV was only 54% under the identical experimental conditions. Moreover, a possible mechanism for the photocatalytic activity has proposed by density of states (DOS) calculations.

Luminescent sensing of Cu2+, CrO42− and photocatalytic degradation of methyl violet by Zn(II) metal-organic framework (MOF) having 5,5′-(1H-2,3,5-triazole-1,4-diyl)diisophthalic acid ligand

A porous Zn(II) metal–organic framework (MOF) [Zn(H2L)(4,4′-bipy)0.5]n (1) has been selected and its luminescence sensing for cations and anions as well as the photocatalytic property against methyl violet have been explored. Luminescence studies indicated that 1 could be an efficient multifunctional fluorescent material for highly sensitive detection of metal cation Cu2+ and anions CrO42−. The luminescence intensity of 1 was found to decrease proportionately with increase in the concentration of Cu2+ and CrO42−. Furthermore, the photocatalytic property of 1 for degradation of the methyl violet (MV) have been explored and a possible photocatalytic mechanism have been proposed using density of states (DOS) and partial DOS (pDOS) calculations.

Fluorine-doped nanocrystalline ZnO powders prepared via microwave irradiation route as effective materials for photocatalyst

In this report, we have successfully synthesized nanocrystalline pure and F doped ZnO prepared by one-step microwave irradiation method without using any post annealing treatment. The effect of F dopant on structural, morphological and optical properties were systematically investigated by using powder X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), Raman spectra, UV–Vis absorption spectra and photoluminescence spectra analysis. XRD results reveals that both pristine and F doped ZnO had a hexagonal wurtzite type structure and the results are in good agreement with standard JCPDS data (card no. 36-1451). FESEM images showed that random platelets morphology with average diameter around 50–35 nm. A considerable red-shift in the absorption edge and decreasing the band gap of pure ZnO (3.32–3.12 eV) was confirmed though UV–Vis spectra. The defect in crystal and oxygen vacancy was analyzed through PL spectra analysis. The photocatalytic activities of the catalyst powders were evaluated by photocatalytic degradation of methyl violet (MV) and rhodamine B (RhB) and the results showed that the doping of F into ZnO nanoparticles could enhance photocatalytic activity compared to the undoped ZnO nanoparticles, this could be due to reduction of band gap and superior textural properties. The improved photocatalytic mechanism by F doping was also discussed in detail.

Preparation of a p-n heterojunction BiFeO3@TiO2 photocatalyst with a core–shell structure for visible-light photocatalytic degradation

Magnetically separable bismuth ferrite (BiFeO3) nanoparticles were fabricated by a citrate self-combustion method and coated with titanium dioxide (TiO2) by hydrolysis of titanium butoxide (Ti(OBu)4) to form BiFeO3@TiO2 core–shell nanocomposites with different mass ratios of TiO2 to BiFeO3. The photocatalytic performance of the catalysts was comprehensively investigated via photocatalytic oxidation of methyl violet (MV) under both ultraviolet and visible-light irradiation. The BiFeO3@TiO2 samples exhibited better photocatalytic performance than either BiFeO3 or TiO2 alone, and a BiFeO3@TiO2 sample with a mass ratio of 1:1 and TiO2 shell thickness of 50–100 nm showed the highest photo-oxidation activity of the catalysts. The enhanced photocatalytic activity was ascribed to the formation of a p-n junction of BiFeO3 and TiO2 with high charge separation efficiency as well as strong light absorption ability. Photoelectrochemical Mott–Schottky (MS) measurements revealed that both the charge carrier transportation and donor density of BiFeO3 were markedly enhanced after introduction of TiO2. The mechanism of MV degradation is mainly attributed to hydroxyl radicals and photogenerated electrons based on energy band theory and the formation of an internal electrostatic field. In addition, the unique core–shell structure of BiFeO3@TiO2 also promotes charge transfer at the BiFeO3/TiO2 interface by increasing the contact area between BiFeO3 and TiO2. Finally, the photocatalytic activity of BiFeO3@TiO2 was further confirmed by degradation of other industrial dyes under visible-light irradiation.