Photocatalytic Dye Degradation Research Articles

Synthesis and characterization of Fe doped ZnO nanoparticles for the photocatalytic degradation of Eriochrome Black-T dye

Synthesis and characterization of Fe doped ZnO nanoparticles for the photocatalytic degradation of Eriochrome Black-T dye

Multifaceted properties of an engineered three-dimensional Zn(ii)–metal–organic coordination polymer: synthesis, crystal structure, efficient photocatalytic degradation of an organic dye and selective luminescent sensing

Luminescent sensing of volatile organic solvents (VOCs), anions, cations, etc., and photocatalysts for aromatic dyes are two of the many emerging applications for metal-organic frameworks and coordination polymers (MOFs/CPs).

Tailoring graphene-oxide and reduced-graphene-oxide with NaNO3 and CaCl2 catalysts with enhanced photo-catalytic degradation of methylene blue dye.

This study employed various experimental techniques to produce graphene oxide (GO) under different conditions, such as the inclusion or exclusion of NaNO3, and reduced graphene oxide (RGO) with or without the catalyst CaCl2. The procedure of decreasing RGO was carried out using the reducing agent NaBH4. Moreover, the prepared mixtures were utilized in the degradation process of methylene blue (MB) dye using photo-catalysis, with exposure to both ultraviolet (UV) light and sunlight. When exposed to UV and sunlight irradiation, WN-GO showed rapid and ecologically friendly breakdown of MB dye in comparison to N-GO. WN-GO exhibited exceptional adsorption capabilities, surpassing other tested materials like N-GO, WN-C-RGO and C-RGO. Although WN-C-RGO has demonstrated satisfactory performance in terms of photo-catalytic degradation, as the concentration-time graph of the MB dye revealed significant degradation, with a reduction of up to 90% and 62.5% under UV light and sunlight exposure, respectively. These results offer insightful information on the potential of graphene-based materials to address other environmental issues, particularly in the areas of water treatment.

Synthesis, characterization and application of ternary composite of CdS/MoS2/reduced graphene oxide for photocatalytic degradation of sunset dye

Environmental impacts, energy applications, photocatalysis on semiconductor-based hybrid materials has drawn a lot of interest recently. Having a gap in between 1 and 2 eV, the Transition Metal Dichalcogenide (TMDSc) group of materials can be good option for a two-dimensional material. A straightforward microwave synthesis technique was used for synthesizing CdS/MoS2/rGO ternary composite SEM images and XRD analysis revealed the presence of CdS/MoS2/rGO in the nanocomposite particles. The crystal structure of CdS and MoS2 is hexagonal. In terms of wavelength, the greatest absorption peak of CdS is 514 nm, and its bandwidth is 2.42 eV, whereas MoS2 band width is between 1.8 - 1.9 eV. The size of CdS is 1 nm and MoS2 is 500 nm. The average size of the nanocomposite was 1 nm. In the present work the photocatalytic activity of sunset yellow dye is checked by ternary composite nanoparticles of CdS under visible light irradiation. The photocatalytic activity is determined by various factors like effect of catalyst in which amount of catalyst varies, effect of different pH, variation in the conc. of dye and the effect of different temp. As the time interval rises by 180 min from 10 min, the dye's degradation efficiency enhances from 33% to 95%.

Photocatalytic degradation of methylene blue dye with biosynthesized Hematite α-Fe2O3 nanoparticles under UV-Irradiation

Nanoparticles (NPs) are currently extensively utilized in various fields, such as medicine, solar energy, water treatment, and pollution detection. In this study, hematite (α-Fe2O3) NPs were synthesized using a cost-effective and environmentally friendly method involving the utilization of a biomass filtrate of Mentha pulegium as a bio-reducer. The structural and optical properties of the α-Fe2O3 NPs were investigated using techniques such as X-ray diffraction (XRD), UV-Visible spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). X-ray diffraction analysis confirmed the crystalline nature of the α-Fe2O3 NPs, with a crystallite size ranging from 16.92 to 35.38 nm. The α-Fe2O3 NPs exhibited absorption at 290 nm, indicating a direct bandgap ranging from 3.25 to 3.90 eV and an indirect bandgap of 2.69 to 3.59 eV, as determined from the UV-Visible spectra. FTIR analysis revealed a peak at 486 cm−1, attributed to the vibration of the α-Fe2O3 NPs, confirming the formation of the nanoparticles. SEM imaging showed that the green-synthesized α-Fe2O3 NPs generally exhibited a hexagonal shape. The efficiency of the biosynthesized α-Fe2O3 NPs was evaluated for the rapid degradation of Methylene Blue (MB) dye, achieving a degradation rate of up to 78% after 120 min. These findings could serve as a foundation for the development of highly effective photocatalytic degradation methods that may be employed in the future for the removal of hazardous dyes from contaminated water.

Fabrication of carbon-based materials derived from a cobalt-based organic framework for enhancing photocatalytic degradation of dyes.

The pyrolysis of metal-organic frameworks (MOFs) has emerged as a promising route to synthesize carbon/metal oxide-based materials with diverse phase compositions, morphologies, sizes and surface areas. In this paper, 1,3,5-benzoic acid (BTC) and 2,4,6-tri(4-pyridinyl)-1-pyridine (TPP) were used as ligands to prepare a novel cobalt-based MOF (Co-MOF) which was used as a precursor to obtain five carbon-based materials at different temperatures (Co-C200/400/600/800/1000). Furthermore, five dyes were used as degradation targets to investigate the photocatalytic degradation performance of the title materials under UV light irradiation. Co-C1000 exhibited the best photocatalytic degradation performance for methyl orange (MO), and the degradation rate could reach 99.21%. The enhanced photocatalytic activity was attributed to narrower band-gaps and a synergistic effect originating from the well-aligned straddling band structures between Co/CoO/Co3O4 and C, also resulting in a faster interfacial charge transfer during the photocatalytic reaction. This study will aid in the development of photocatalysts generated from carbon-based materials via the pyrolysis transformation of MOFs, therefore greatly enhancing the photocatalytic performance.

Pyridine-amide-based hetero-copper iodide for the photocatalytic degradation of dyes and aerosol discolouration of VOC gases

The new hybrid cuprous iodide is the first copper iodide polymer with both photocatalytic and gas-chromic properties. This work extends the development of photochemical sensors for the more rapid and sensitive detection of VOC gases.

Water pollution remediation: Synthesis and characterization of poly(o‐methylaniline)/ZnO/rGO composite for photocatalytic degradation of dyes

AbstractWater pollution is growing at an alarming rate, particularly due to the colored wastewater released by the various industries into aquifers and fresh water sources, and in some extreme cases, they have reached the water table. Faisalabad, a city in Pakistan where there is an industrial cluster of textiles dyeing and manufacturers, water table has become undrinkable. The presence of hazardous dyes and chemicals imposes serious health issues on humans, animals, and plants. The treatment of such toxic dye effluents is crucial and could be done by efficient degradation methods such as photocatalysis. The current study presents synthesis of poly(o‐methylaniline)/zinc oxide/reduced graphene oxide nanocomposite (POMA/ZnO/rGO NC) using a chemical oxidative polymerization process and explores its properties as a photocatalyst by demonstrating degradation of three dyes. The composite was characterized using X‐ray diffraction (XRD), Fourier‐transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), photoluminescence emission spectroscopy (PL), Brunauer Emmett–Teller analysis (BET), and UV–visible spectroscopy (UV–visible). Further, the photocatalytic activity of POMA/ZnO/rGO NC was evaluated and compared by degrading the direct yellow 12 (DY 12), congo red (CR), and malachite green (MG) dyes in aqueous media under UV irradiation. The results indicated that after 110 min, POMA/ZnO/rGO composite degraded the dyes by 92% (DY 12), 86.1% (CR), and 82.1% (MG), respectively. Moreover, kinetic studies of the photocatalyst were also performed along with reusability test, total organic carbon, chemical oxygen demand, and degradation mechanism.

A deeper insight into the evaluation of water-in-oil amicroemulsion templated samarium sulfide nanospheres: exploring its role in pickering emulsion formulation for photocatalytic dye degradation and synthesis of PANI@Sm2S3 nanocomposites.

This study examines the effectiveness of W/O microemulsion-mediated Sm2S3 nanospheres in pickering emulsion-based crystal violet (CV) dye degradation and PANI@Sm2S3 nanocomposite synthesis. The evaluation of nanospheres inside the core of reverse micelles was performed through DLS, TEM and FESEM analyses. The formation of nanospheres involve two phases: a nucleation phase (5-30 min) and growth phase (30-120 min). Through in situ hydrophobization of negatively charged (with a zeta value of -4.47 mV at neutral pH) Sm2S3 nanoparticles (0.1 wt%) with a suitable amount of a cationic CTAB surfactant, a stable O/W pickering emulsion was developed. 0.1 wt% Sm2S3in situ hydrophobized with 2.7 mM CTAB offered a stable pickering emulsion with a diameter of 23 μm after 1 day of storage. This pickering emulsion improves the local concentration of CV by efficiently encapsulating dye molecules inside the core of emulsion droplets. Therefore, dye molecules get numerous opportunities to interact with the Sm2S3 photocatalyst and efficiently degrade. The pickering emulsion stabilised by 0.1 wt% of Sm2S3 nanoparticles in situ hydrophobized with 2.7 mM of CTAB results in almost 100% degradation. Moreover, using only solid Sm2S3 (having wt% of 0.025 or 0.075) as a pickering stabiliser, new PANI@Sm2S3 spherical nanocomposites were synthesised via pickering emulsion polymerization. The formation of PANI@Sm2S3 composites was identified via UV-vis, IR, and 1H-NMR investigations. The analysis of FESEM images showed that the amount of nanoparticles used in the dispersion (for 0.025 wt%, 35 nm and 0.075 wt%, 29 nm) strongly influences the size and shape of the composites.

Facile assembly of BiOI/GO composites with enhanced photocatalytic activity for NO photooxidation under visible light irradiation

Facile assembly of BiOI/GO composites with enhanced photocatalytic activity for NO photooxidation under visible light irradiation

Enhancement of the photocatalytic activity of rGO/NiO/Ag nanocomposite for degradation of methylene blue dye.

The current study focuses on boosting the photocatalytic ability of reduced graphene oxide (rGO) by decorating the rGO nano-sheets with nickel oxide (NiOx) and silver (Ag) nanomaterials. The developed ternary nanomaterials were investigated using FTIR, XRD, FESEM, TEM, Raman, and UV-vis to evaluate the photo-degradation process. The rGO/NiOx/Ag ternary system showed promising photocatalytic dye degradation under simulated sunlight irradiance. The addition of NiOx and Ag nanomaterials widened the catalytic activity spectrum from the visible region to the UV-region. Besides, these materials hindered the electron-hole recombination, boosting the catalytic activity. The reusability results also clearly showed that the synthesized ternary nanomaterials have good reproducibility and stability for photocatalytic degradation of industrial wastewater.

Effect of Lanthanum Loading on the Photocatalytic Degradation of Brilliant Yellow and Acid Blue Dyes in Visible Light and Sunlight over La2O3-TiO2 Nanocomposites

La-doped TiO2 nanocomposites were synthesized using the sol-gel process with different proportions of lanthanum doping (1-5 wt.%). The synthesized nanocomposites were analyzed thoroughly by X-ray diffraction (XRD), nitrogen adsorption, scanning electron  microscopy (SEM) with extended X-ray diffraction (EDAX), transmission electron microscopy, ultraviolet-visible DRS spectra for optical  properties, photoluminescence (PL) for emission behaviours, Fourier transform infrared (FTIR) spectroscopy (FTIR) for chemical  bonding analysis and X-ray photoelectron spectroscopy (XPS) for surface chemical composition. The XRD analysis confirmed the  anatase phase for all synthesized La-TiO2 nanocomposites. The UV-Vis spectra showed an increased absorption in the visible range  and a slight red shift of binding energy as the % La doping increased from 1-5 wt.%. Similarly, the binding energy values varied from  3.02 to 2.75 eV with increased La doping. These nanocomposites exhibited the photocatalytic activity achieving 99% degradation of acid blue dye and 96% degradation of brilliant yellow dye in the presence of visible light irradiation. Scavenger studies indicated that the  dye degradation was suppressed, suggesting the involvement of superoxide (O2–), hydroxyl radical (OH•) and holes (h+) in the reaction  mechanism.

Construction of visible light responsive GO-stimulated In2O3/BiVO4 Z-scheme heterostructure: Photocatalytic degradation of dye & antibiotics, anticancer activity and toxicity elimination

A ternary nanocomposite, In2O3/GO/BiVO4, was created using the hydrothermal process, establishing a heterojunction between In2O3 and BiVO4 with the addition of graphene oxide nanosheets. The synthesized materials underwent characterization using various standard analytical techniques, including diffuse reflectance spectroscopy (DRS), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), electron spin resonance spectroscopy (ESR), energy-dispersive X-ray (EDX), and transmission electron microscopy (TEM). The developed materials showed notable efficacy in degrading MB dye and antibiotics such as ciprofloxacin and tetracycline, when exposed to visible light in an aqueous suspension. The photocatalyst, 10 wt% In2O3/GO/BiVO4 (10IBG) showed better activity compared with the pure and other composite materials. The enhanced activity could be attributed to the synergistic effects of charge carrier separation and electron mediation facilitated by graphene oxide via Z-scheme pathway. The successful integration of graphene oxide in the heterostructure underscores its potential as a promising strategy for developing high-performance photocatalysts for the elimination of organic pollutants. Furthermore, the mechanism investigation underlying photocatalytic degradation of organic pollutants using the 10IBG heterostructure photocatalyst is conducted through trapping experiments, which indicates that the degradation is primarily contributedby superoxide radical anions (O2•-) and hydroxyl radicals (•OH). Moreover, 10IBG photocatalyst displayed remarkable anticancer activity against A549 lung cancer cell lines, whereas the cell viability was reduced from 18% in the dark medium to 58% when exposed to visible light. In terms of toxicity assessment, the 10IBG heterostructure photocatalyst demonstrated quick eradication of antibiotic toxicity and established itself as a promising and cost-effective photocatalyst for wastewater treatment.

Photocatalytic degradation of methylene blue dye using biogenic copper oxide nanoparticles and its degradation pathway analysis

In order to remove the toxic organic dyes from the environment, biogenic inorganic semiconductor nanoparticle based photocatalyst has drawn attention due to its low cost, simplicity, eco-friendliness, high efficiency and ease of process. Herein, Copper oxide nanoparticles (CuO NPs) were prepared by using Syzygium Cumini seed extract as reducing as well capping agent. The formed CuO NPs were characterized by X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), B.E.T isotherm, UV–Visible spectroscopy, Scanning Electron Microscopy (SEM) and X-ray Photoelectron Spectroscopy (XPS) analysis. The CuO NP’s photocatalytic activities have been analyzed with methylene blue (MB) degradation. The effect of the catalyst for MB degradation has been optimized at various catalyst amount, dye concentration and pH environments. The results showed that, the CuO NPs can effectively degrade 97 % of MB in 60 min, following pseudo first order kinetics, while the rate constant was found to be 0.06 min−1. The present catalyst material showed 95 % MB degradation with similar morphology of freshly prepared catalyst even after five consecuetive reuse cycles and worked effectively over a wide pH range. The degradation pathway of MB was studied through the HR-MS technique.

Coal fly ash-supported ZnO-promoted TiO2 towards UV photocatalytic degradation of anthraquinone dye: Parametric optimization, kinetics and mechanism studies

Heterogeneous photocatalysis via combination of catalyst and UV irradiation is one of the most promising advanced oxidation processes for degradation of water-soluble organic contaminants. Herein, different photocatalysts (ZnO/CFA, TiO2/CFA, and TiO2-ZnO/CFA) were synthesized via sol-gel and impregnation techniques and applied for the degradation of acid blue 25 (AB25) dye in aqueous solution under UV light in a photoreactor. Various spectroscopic techniques (XRF, XRD, BET, FTIR, UV–vis DRS, TEM and EDS) were employed to evaluate the chemical structure, functional groups, textural, and optical properties of the binary and ternary composites. TiO2-ZnO/CFA displayed rapid degradation of AB25 as compared to ZnO/CFA and TiO2/CFA, owing to the dualistic photocatalytic sites. The prepared TiO2-ZnO/CFA composite was used in synergy with the photoreactor for photocatalytic degradation process optimization, and the optimum degradation conditions in relation to initial AB25 concentration (10 mg/L), UV light intensity (18 W/m2), flow rate (12.5 L/h), and irradiation time (150 min) as input parameters were determined using Taguchi design approach. The maximum photocatalytic degradation efficiency was 98.79±0.94% under those aforementioned conditions, indicating that the synergies between the photoreactor and the TiO2-ZnO/CFA photocatalyst resulted in the effective destruction of AB25 dye molecules. Furthermore, the spent photocatalyst was easily removed from the degraded solution and reused up to nine times. After 150 mins of UV irradiation with TiO2-ZnO/CFA photocatalyst, almost complete mineralization of AB25 solution was achieved.

Efficient adsorption and photocatalytic degradation of textile dye from metal ion-substituted ferrite for environmental remediation

Efficient adsorption and photocatalytic degradation of textile dye from metal ion-substituted ferrite for environmental remediation

WS2 nanoparticles screen printed cotton for dual piezo- and photocatalytic antibacterial and dye degradation performance

Pristine cotton fabric was screen printed with tungsten disulfide (WS2) nanoparticles (NPs). The ability of the resulting fabric to degrade dye and inhibit bacterial growth through piezo- and photocatalysis was examined. During a 2 h bacterial contact time, the piezocatalytic study of unwashed WS2-printed fabric reduced E. coli and S. aureus by 93% and 90%, respectively. During photocatalysis, the modified cloth reduced the growth of E. coli and S. aureus by 91% and 88%, respectively. After washing (15 cycles), both the piezo- and photocatalytic performance of the modified fabric demonstrated more than 83% bacteria inhibition. The maximum piezocatalytic Rhodamine B (RhB) dye mineralization of 65% was attained in 240 min as opposed to 11% in pure cotton. The photocatalytic study of WS2-coated fabric degraded RhB dye by 46%, while only 11% of the RhB dye was mineralized by the pure cotton fabric in 240 min.

Simple co-precipitation synthesis of activated carbon-cobalt ferrite (AC-CoFe2O4) nanocomposites: enhanced photocatalytic dye degradation and antimicrobial activity

Abstract In this present work, spinel cobalt ferrite nanoparticles (CoFe2O4 NPs) and activated carbon-CoFe2O4 nanocomposites (AC-CoFeO4 NCs) were synthesized by simple co-precipitation method and used for photocatalytic dye degradation (PCD) of rhodamine-B (Rh-B) dye. The antimicrobial study of the as-synthesized CoFe2O4 NPs was also performed. The as-synthesized CoFe2O4 NPs and AC-CoFe2O4 NCs were analyzed by ultraviolet spectroscopy (UV), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) studies, scanning electron spectroscopy (FE-SEM) techniques. Powder XRD analysis showed that the as-synthesized CoFeO4 NPs and AC-CoFeO4 NCs had average particle size of 18 nm and 46 nm, respectively. The FE-SEM showed that the CoFe2O4 samples have sphere like morphology and were well decorated on activated carbon in order to provide high surface area. AC-CoFe2O4 NCs have effectively used for the PCD of Rh-B dye with high efficiency. Furthermore, spinel CoFe2O4 NPs acted as a more effective antimicrobial agent against Gram-negative and Gram-positive bacterial strains. Moreover, AC-CoFe2O4 NCs can be used as the precursor materials for supercapacitor, sensors etc.

Bimetallic ternary Cobalt Bismuth Iodide for visible-light-drive N photocatalytic degradation of industrial dyes (TB)

In the water treatment process, sustainable, easy, effective and less expensive technique is always challenging and demanding. For this perspective, metal iodide shows great efficiency towards dye degradation processes. The present work explores the degradation of toluidine blue with the help of synthesized cobalt bismuth iodide (CBI). Structural and textural features show that on the sheet of bismuth iodide, tiny particles of cobalt iodide are uniformly distributed. The effect of various parameters such as – initial pH, dye concentration, amount of cobalt bismuth iodide and exposure of light intensity were examined. The experimental results indicate that cobalt bismuth iodide is having the advantage of the photodegradation process and is considered a significant new photocatalyst. The kinetics involved in the degradation was found to follow the pseudo-first-order kinetic model. At last, we discuss possible mechanisms for the mineralization of toludine blue. This study reveals a new choice for the potential application of cobalt bismuth iodide for the degradation of organic pollutants in water streams.

Effective approach to improve photocatalytic dye degradation ability of ZnO based nanopowder: simultaneous cationic and anionic doping, and enzyme coupling

Effective approach to improve photocatalytic dye degradation ability of ZnO based nanopowder: simultaneous cationic and anionic doping, and enzyme coupling