Photocatalyst For Degradation Of Dye Research Articles

Photocatalytic degradation of Rhodamine B dye over oxygen-rich bismuth oxychloride Bi24O31Cl10 photocatalyst under UV and Visible light irradiation: Pathways and mechanism

Photocatalytic removal of organic pollutants from wastewater has recently garnered significant attention due to its environmental and ecological significance. In this study, a bismuth-rich bismuth oxychloride (Bi24O31Cl10) was synthesized using a single-step solid-state reaction and applied as a photocatalyst for the degradation of rhodamine B in aqueous solution. The photocatalyst was prepared through an eco-friendly solid-state method by mixing bismuth oxide (Bi2O3) and bismuth oxychloride (BiOCl), followed by direct annealing at 600°C. The synthesized material was characterized through various techniques, including X-ray diffraction (XRD), Fourier-transform infrared (FTIR), Raman spectroscopy, scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) surface area analysis, energy dispersive X-ray spectroscopy (EDS), diffuse reflectance, UV-Visible, and photoluminescence (PL) spectroscopies. The electronic structure of the Bi24O31Cl10 bulk material was analyzed using Density Functional Theory (DFT).Rietveld refinement confirmed the formation of a pure monoclinic Bi24O31Cl10 phase with the space group P2/c, and the XRD patterns indicated well-crystallized material. SEM revealed micron-sized crystallites, while BET surface area analysis showed a value of 22.546 m²/g, suggesting that a larger surface area could enhance photocatalytic performance. The band gap of the material was determined to be 2.88 eV, with an absorption edge at 430 nm, indicating a promising response to visible light.The photocatalytic activity of Bi24O31Cl10 was demonstrated by the degradation of rhodamine B (RhB), with complete degradation achieved in 90 minutes under UV light. Under visible light, 98% degradation efficiency was reached after 180 minutes. Kinetic studies showed that the degradation followed a pseudo-first-order model. Optimal conditions for maximum degradation were found at a solution pH of 5, a catalyst concentration of 1 g/L, and a dye concentration of 5 mg/L. Remarkably, the photocatalyst exhibited excellent reusability, maintaining high efficiency over five cycles, with only a slight decrease from 100% to 90%.Trapping experiments identified that reactive species such as superoxide radicals (∙O2-) and hydroxyl radicals (∙OH) played key roles in the photocatalytic process. The possible reaction mechanism was proposed, and degradation products were monitored using liquid chromatography-mass spectrometry (LC-MS), allowing for the elucidation of the degradation pathways of RhB. Additionally, the photocatalyst’s effectiveness was tested on Methyl Orange (MO) and Methylene Blue (MB), achieving nearly 100% degradation for MO and 41% for MB under UV light. This research highlights the significant potential of Bi24O31Cl10 as a photocatalyst for dye degradation in wastewater treatment.

Enhanced photocatalytic degradation of methylene blue dye using CuO nanoparticles from the fruit extracts of Diplocyclos palmatus (L) C. Jeffrey for wastewater remediation

ABSTRACT The degradation of synthetic organic dyes through photocatalysis requires structured nanoparticles (NPs). Copper oxide (CuO) NPs were used as the newest developed catalyst for the organic dye degradation under the irradiation of sunlight: The metal oxide NPs were synthesized using the fruit extract of Diplocyclos palmatus (L) C. Jeffrey. UV–visible light spectra showed an absorption band for CuO NPs at 277 nm. X-ray diffraction confirmed the monoclinic phase of CuO NPs. Scanning electron microscopy confirmed rod-shaped stacked particles. Energy-dispersive X-ray spectra indicating the presence of Cu in oxide form. For the degradation of methylene blue dye (MB), CuO NPs were used as photocatalyst for dye degradation under sunlight irradiation. This study confirmed the effects, such as irradiation time, concentration, pH, and catalyst dosage. The CuO NPs showed high photocatalytic degradation, degrading 90% of the dye in 120 min. The increased degradation of dye was observed on exposure to longer irradiation time. The increased concentration of dye resulted in a decreased rate of photodegradation. 95% degradation achieved at pH 9 showing that the pH medium also enhances the degradation. A higher dye degradation percentage was achieved by increasing the higher catalyst dosage of 0.013 g degraded 93% of dye. Thus in the treatment of wastewater containing pollutants, the synthesized CuO NPs acted as an efficient photocatalyst.

Selenium-enriched MoSe2 as an effective electrode material for supercapacitors and a photocatalyst for dye degradation

In this research, we synthesized 2D-corrugated sheet-like nanostructure of MoSe2 (MS) and selenium-enriched MoSe2 (MS-S) using a hydrothermal method to evaluate the electrochemical and photocatalytic performance. Electrochemical assessments revealed that MS-S exhibits an outstanding specific capacitance of 275 F g−1 at a scan rate of 10 mV s−1, showcasing its suitability as a symmetric supercapacitor. Particularly noteworthy is the outstanding energy density observed in MS-S, reaching 36.72 Wh kg−1, a value nearly seven times higher than that of MS (5.33 Wh kg−1). Furthermore, MS-S demonstrated remarkable capacitance retention, retaining 68 % of its initial capacitance even after 2000 cycles. In contrast, MS exhibited only 17 % retention over the same cycle count. Additionally, we evaluated the photocatalytic efficacy of the MS and MS-S samples in degrading rhodamine B (RhB) dye in a solution utilizing a 30 W white LED light source. Impressively, after 50 minutes of light exposure, MS-S displayed an outstanding degradation efficiency of up to 86 %, significantly surpassing the performance of MS. These results emphasize the immense potential of MS-S as a highly promising material suitable for a range of applications, including supercapacitors and dye degradation.

Polyvinyl alcohol/polyethyleneimine grafted carbon oxynitride composite nanofiber membranes with the synergistical enhanced photocatalytic degradation and bactericidal performance

AbstractGraphitic carbon nitride (g‐C3N4) has received much attention as a metal‐free photocatalyst for dye degradation and sterilization. However, the low photocatalytic bactericidal activity and the difficulty in recycling have limited its applications. Here, oxidatively modified g‐C3N4 grafted with polyethyleneimine (PEI) nanofiber membranes (PVA/PEI‐OCN) was reported to enhance the photocatalytic activity. The modification by PEI grafting could reduce the recombination rate of photogenerated carriers and lead to more electrons for the photocatalytic reaction. In addition, electron spin resonance (ESR) results showed that the generation of reactive oxygen species (˙OH, ˙O2− and 1O2) were significantly enhanced in photocatalysis, leading to the significant enhancement of photocatalytic bactericidal activity and dye degradation. Furthermore, the PVA/PEI‐OCN nanofiber membranes prepared by electrospinning had smooth surfaces and uniform fiber formation, with an average diameter of 380 ± 60 nm. The tensile strength was about 73.5% higher than that of PVA nanofiber membranes. The inhibition diameter of PVA/PEI‐OCN‐4 against Escherichisa coli (E. coil) could reach 20 ± 0.2 mm, and the maximum degradation efficiency of methylene blue solution (10 mg/L) could reach 92.8% within 120 min. This work provided an effective paradigm for the rational design of metal‐free photocatalytic materials for elimination of bacterial and dye contamination.

Bi Quantum Dots Supported on BiOBr Nanoparticles and Loaded on Porous ZnO as a Photocatalyst for Dye Degradation and H2 Production

Bi Quantum Dots Supported on BiOBr Nanoparticles and Loaded on Porous ZnO as a Photocatalyst for Dye Degradation and H₂ Production

Facile synthesis of Cu2S-NiS2 nanocomposite with highly active visible light photocatalyst for dye removal and biological evaluation

Earth abundant metal sulphides such as Cu2S and NiS2 are potential materials to be used as photocatalysts because of their advantageous optical and biological aspects. In this research, a low-cost, high-speed, one step combustion production of novel Cu2S-NiS2 nanocomposite (NCs) was successfully developed. They are integrally characterized and evaluated as photocatalysts for dye degradation and biological uses. The synthesized NCs were characterized by XRD, FTIR, SEM, TEM, EDAX, UV–Visible and PL. XRD data is well matched with JCPDS 03–1071 and 73–574 which correspond to Cu2S and NiS2 nanoparticles (NPs) respectively. FT-IR spectrum exhibits the existence of metal-sulphur bonding in Cu2S-NiS2 NCs. The optical energy band gap of Cu2S-NiS2 NCs was found 2.30 eV. Under visible light irradiation, the photocatalytic activity of Cu2S-NiS2 NCs on rose bengal dye was investigated. Cu2S-NiS2 NCs is more efficient photocatalyst than individual metal sulphide NPs. Also, an important aspect of this study was the exploration of the antimicrobial, antioxidant and antihemolytic properties of pure NPs and Cu2S-NiS2 NCs. The results from the biological screening exposed the fact that the Cu2S-NiS2 NCs demonstrated significantly higher pharmacological activities in comparison to pure NPs.

A Zn-Polyrotaxane One-Dimensional Coordination Polymer as a Multi-responsive Luminescence Sensor and Photocatalyst for Dye Degradation

A Zn(II)-based polyrotaxane 1D coordination polymer, {[Zn(Or)(Bimb)(H2O)]2·2H2O} n , 1 (Or = orotate; Bimb = 1,4-bis[(1H-imidazol-1-yl)methyl]benzene), has been synthesized. 1 provides for luminescent sensing of acetone, Fe3+, MnO4 –, nitrofurantoin (NFT), uric acid (UA), and sucrose. The coordination polymer displays exceptional intensity quenching of ∼96.1% with 200 mg/dl of sucrose in aqueous solution. In addition, the reactivity of 1 to photocatalytically degrade the organic dye methylene blue (MB), a hazardous organic pigment, was established. 1 was able to degrade the dye due to the generation of reactive oxygen species.

Synthesis of NFO-immobilized yeast nanobiocomposite for ultrasound-assisted photo-fenton degradation of methylene blue by using central composite design

In this study, we synthesized nano-NiFe2O4-immobilized Saccharomyces cerevisiae yeast composites (NFO-SC) and investigated their photo-deterioration efficiency for methylene blue (MB) using central composite design (CCD). The morphological features of NFO-SC were comprehensively characterized through scanning electron microscopy (SEM), UV–VIS spectroscopy, Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). Initial XRD analysis of pristine NFO indicated an average particle size of 20 nm. Subsequent XRD, FTIR, SEM, and UV–VIS analyses were performed before and after immobilization, confirming the surface modification of yeast cells by NFO. The XRD results for NFO-SC revealed a reduced average particle size of nickel nano-ferrite (NFO) to 14 nm. The NiFe2O4-SC composite exhibited an impressive 99% MB deterioration efficiency under optimized conditions: 0.020 g of NFO-SC dosage, pH 4.5, initial MB concentration of 20 mg/L, and a photo-irradiation time of 120 min. Photo-catalytic activity was evaluated through UV–VIS spectroscopy and FTIR analysis, demonstrating that the NiFe2O4-SC composite outperformed pristine yeast and pure NFO in MB degradation efficiency. This study highlights the potential of the NiFe2O4-SC composite as an photo-catalyst for dye degradation, showcasing its promise for applications in environmental remediation processes.

Study of Bi-functional Applications of ZnO Nanoparticles Synthesized via Sonochemical Route

The sonochemical synthesis involved the dispersion of zinc oxide (ZnO) precursor in a suitable solvent, followed by ultrasonic irradiation to induce chemical reactions and nucleation of ZnO nanoparticles. The resulting nanomaterials exhibited a uniform particle size distribution, which is crucial for their photocatalytic efficiency. ZnO nanoparticles with a uniform particle size of 25 nm were successfully synthesized using a sonochemical route and were employed for the degradation of direct green and fast orange dyes under UV light irradiation. The band gap of the ZnO nanoparticles was determined to be 3.35 eV, indicating its potential as a photocatalyst for dye degradation. The degradation efficiency of the dyes was evaluated by monitoring the change in their concentration over time. The ZnO nanoparticles demonstrated excellent photocatalytic activity, efficiently degrading both dyes within a relatively short duration. The electrochemical studies further confirmed the potential applicability of the synthesized ZnO nanoparticles in various electrochemical systems. The ZnO electrode that was produced could detect lead in an acidic solution. The ZnO electrode is a promising electrode material for making sensor applications because of its higher electrochemical behaviour. Overall, this research contributes to the development of efficient and environmentally friendly approaches for wastewater treatment and lead sensor.

Nanocomposite of starch, gelatin and itaconic acid-based biodegradable hydrogel and ZnO/cellulose nanofiber: A pH-sensitive sustained drug delivery vehicle

In recent years, hydrogels as drug carriers have been receiving great interest due to their ability to change their behavior in response to one or more external stimuli. However, their initial burst release profile limits their practical applications. Therefore, we prepared a bio-based hydrogel nanocomposite (HNC) using starch, itaconic acid, acrylic acid and gelatin in the presence of CNF/ZnO-based nanohybrid (ZONH) and used it to evaluate the pH-sensitive drug release properties in different pH solutions. The prepared HNCs were analyzed using various spectroscopic and microscopic techniques. The BET analysis and swelling test of the HNC indicated improved porosity and swelling capacity due to the addition of ZONH. From the drug release study, sustained drug release rate was observed at pH 4 than those at pH 7.4 and 9, indicating controlled release as well as pH responsive behavior of the HNC. Moreover, the drug released HNC was reused as a photocatalyst for dye degradation and achieved good degradation (%). The antibacterial activity of ZONH and HNC was observed against EC and SA bacterial strains from the antibacterial test. In summary, the prepared HNC can be considered as a potential sustainable DDS for biomedical applications as well as a photocatalyst for dye contaminated water treatment.

Two-Dimensional Cu-Porphyrin Metal-Organic Framework Nanosheet-Supported Flaky TiO2 as an Efficient Visible-Light-Driven Photocatalyst for Dye Degradation and Cr(VI) Reduction.

A series of 2D M(Cu, Zn, Co, and Mn)-TCPP MOFs/TiO2 binary nanocomposites (TCPP = tetrakis(4-carboxyphenyl)porphyrin) were constructed by solvothermal in situ loading of flaky TiO2 on the surface of 2D metal-organic frameworks (MOFs). The influence of different coordination metals on the catalytic activity was studied, and it was found that the 2D Cu-TCPP MOFs/TiO2 nanocomposite exhibited the best photo-Fenton performance. The superior property can be attributed to the high absorption coefficient and ultrathin two-dimensional structure of the 2D Cu-TCPP MOFs nanosheets. Meanwhile, the 2D Cu-TCPP MOFs/TiO2 II heterostructure can effectively promote the separation and transfer of photoformed carriers. Moreover, under visible irradiation, the optimized 2D Cu-TCPP MOFs/TiO2 composite can convert 99.9% of Cr(VI) to Cr(III) within 60 min with methanol as the hole scavenger at pH 3.14. Also, the photocatalytic performance of 2D Cu-TCPP MOFs/TiO2 was maintained after five reaction cycles. Furthermore, the proposed visible-light-driven photocatalysis mechanism of the 2D Cu-MOFs/TiO2 composite was reasonably derived according to experimental results. This study demonstrates the potential of building efficient TiO2-based visible light photocatalysts with 2D metal-porphyrin MOFs.

Mesostructured graphitic carbon nitride composites with silver nanoparticle decoration as the best visible-light-driven photocatalysts for dye degradation and H2 production

Water-splitting photocatalysis on the surface of semiconductors has emerged as a promising approach for wastewater treatment to remove organic pollutants from aqueous media in various industrial fields. However, developing efficient photocatalysts with sufficient activity is challenging owing to the rapid recombination of photogenerated electrons and holes in the available functional materials. Aiming to fabricate photocatalysts to remove pollutants with reduced electron-hole recombination, mesostructured graphitic carbon nitride (MCN) composites made of Ag-doped melamine were designed and synthesized at room temperature. The structural and optical properties of the prepared MCN composite indicate that it is well-suited for use as a visible-light-driven photocatalyst. A morphological analysis using transmission and scanning electron microscopy showed that the Ag nanoparticles were uniformly distributed on the surface of the MCN sheets, promoting the photocatalytic property of the Ag/MCN composites. Adding silver nanoparticles onto MCN facilitates the rapid transfer of photo-generated electrons from MCN to the silver nanoparticles. This is due to the presence of an interfacial electric field across the junctions, leading to a reduction in the recombination process, resulting in superior photocatalytic activity in the degradation of reference organic pollutants like methylene blue and crystal violet, more than 96% of degradation was achieved in the presence of the MCN\\Ag-MCN composite. An astonishing photocatalytic hydrogen evolution rate of 5.24 mmol. g−1.h−1 was observed for the optimized MCN/Ag-MCN nanocomposite.

Pulsed laser ablation-mediated facile fabrication of MoO3/TiO2/rGO nanocomposite as a photocatalyst for dye degradation

In this work, for the first time, the MoO3/TiO2/rGO nanocomposites with different weight ratios of rGO (0%, 5%, 10%, and 20%) were fabricated using pulsed laser ablation technique. The as-fabricated nanocomposites were employed for photodegradation of Methylene Blue (MB) under UV light irradiation. The morphological, structural, and chemical properties of the fabricated photocatalysts were characterized using XRD, TEM, SEM, UV-DRS, XPS, FTIR, TGA, DSC, and PL. Comparative experimental studies displayed that MoO3/TiO2/rGO nanocomposites fabricated with 5% rGO showed the highest photocatalytic degradation (95%) of MB under UV irradiation. This superior photocatalytic performance could be ascribed to the narrow bandgap of the fabricated nanocomposites as well as the synergistic effect of the three components.

A review on ultrasound assisted synthesis of metal oxide and doped metal oxide nanocatalysts and subsequent application as photocatalyst for dye degradation

AbstractIn recent years, research on improving the synthesis of catalysts has been at the forefront because of advancements in nanotechnology and greener conventions. Using ultrasound (US) during nanocatalysts synthesis is one of the green approaches that can yield improved catalyst characteristics under conditions of shorter reaction time and requirement of low temperature and pressure. The current paper aims at giving an insight into US‐assisted synthesis (emphasized on sol‐gel and hydrothermal) of different metal oxide nanocatalysts. It has been elucidated that US‐assisted synthesis gives nanocatalyst with narrower particle size distribution with lower mean size, higher surface area, better morphology with less agglomeration, and higher catalytic activity. Ultrasound has thus been demonstrated to yield improvements in morphological, optical, and electronic properties of the nanocatalysts, however, scalability and industrial application of sonochemical synthesis have not been seen very popular. Some guidelines for future research into the development of novel nanocatalysts and industrial scale‐up studies are also provided. The review also summarizes the application of these metal oxides as photocatalysts for dye degradation or effluent treatment containing dyes, highlighting the fundamentals of photocatalysis as well. A comparative study has been reported for catalysts obtained using the US‐assisted synthesis and conventional synthesis of the photocatalysts in terms of catalytic activity. The benefits of using ultrasound‐assisted synthesis in terms of higher photocatalytic degradation have been clearly demonstrated.

Surfactant assisted FeCo2O4 nanostructure: An efficient counter electrode for dye sensitized solar cell assisted hexagonal and photocatalyst for dye degradation

Surfactant assisted FeCo2O4 nanostructure: An efficient counter electrode for dye sensitized solar cell assisted hexagonal and photocatalyst for dye degradation

Photocatalytic degradation of organic dyes on magnetically separable barium hexaferrite as photocatalyst under conditions of visible light irradiation

In this paper, we present the first attempt to evaluate the role of carboxymethyl cellulose (CMC) as a chelating agent in the sol-gel auto-combustion method of producing barium hexaferrite (BaFe12O19). We also report the application of the system as a photocatalyst for dye degradation. The formation, morphology, and crystalline structure of the synthesized nanoparticles are determined using XRD, SEM, EDS, VSM, FTIR, and TEM techniques. High efficiency under visible light, with a band gap of 1.62eV and a BET surface of 17.93 m2/g, has been observed for the BaFe12O19 catalyst. The operating parameters, such as reaction time, initial dye concentration, light intensity, reusability, and dye type, are studied. Degradation rates as high as 98.26% (Kapp = 0.082min-1) and 89.07% (Kapp = 0.0743min-1) were obtained for cases of methylene blue and malachite green under conditions of visible light irradiations when BaFe12O19 was used. The BaFe12O19 catalyst has been shown to exhibit a high degradation performance for cationic dyes. Furthermore, BaFe12O19 magnetic nanoparticles show excellent reusability for dye degradation because the photocatalyst did not exhibit a significant decrease in its activity even after five runs (81.56%). As a result, the current study confirmed that photocatalytic degradation was a promising technology for saving water and treating wastewater formed from textile dye industries. The technique can be used to study the efficiency of photocatalytic degradation and understand the process of recycling waste effluents under conditions of minimized water use.

Potential effectiveness of visible-light-driven Fe/TiO2 photocatalysts for degradation of dyes contaminated wastewater and their antibacterial activity

Potential effectiveness of visible-light-driven Fe/TiO2 photocatalysts for degradation of dyes contaminated wastewater and their antibacterial activity

Retracted: Recent Review of Titania-Clay-Based Composites Emerging as Advanced Adsorbents and Photocatalysts for Degradation of Dyes over the Last Decade

Retracted: Recent Review of Titania-Clay-Based Composites Emerging as Advanced Adsorbents and Photocatalysts for Degradation of Dyes over the Last Decade

Polymeric ionic liquid-based formulations for the fabrication of highly stable perovskite nanocrystal composites for photocatalytic applications.

Halide perovskite nanocrystals (PNCs) have emerged as potential visible-light photocatalysts because of their outstanding intrinsic properties, including high absorption coefficient and tolerance to defects, which reduces non-radiative recombination, and high oxidizing/reducing power coming from their tuneable band structure. Nevertheless, their sensitivity to humidity, light, heat and water represents a great challenge that limits their applications in solar driven photocatalytic applications. Herein, we demonstrate the synergistic potential of embedding PNCs into polymeric ionic liquids (PILs@PS) to fabricate suitable composites for photodegradation of organic dyes. In this context, the stability of the PNCs after polymeric encapsulation was enhanced, showing better light, moisture, water and thermal stability compared to pristine PNCs for around 200 days.

A Cu medium designed Z-scheme ZnO-Cu-CdS heterojunction photocatalyst for stable and excellent H2 evolution, methylene blue degradation, and CO2 reduction.

Solar photocatalysis has emerged as a pollution-free and inexhaustible technique that has been extensively researched in the domains of environmental remediation and energy production. Herein, we have integrated ZnO and CdS nanoparticles through Cu as a solid-state electron mediator to design a ZnO-Cu-CdS Z-scheme heterosystem via a sol-gel route and further tested this as a photocatalyst for dye degradation, H2 evolution, and CO2 reduction. Within 60 min of visible light exposure, about 97% of methylene blue (MB) is degraded with a degradation rate constant of 0.042 min-1 for the ZnO0.45Cu0.1CdS0.45 catalyst. The MB degradation with this catalyst is 84, 21, 4.8, and 2 times as high as those of ZnO, CdS, ZnO0.5CdS0.5, and Cu0.1ZnO0.9 catalysts. The ZnO-Cu-CdS catalyst manifests an H2 evolution efficiency of 5579 μmol h-1 g-1, which is 169, 41, 3.9, and 3.5 times as high as those of ZnO, CdS, ZnO0.5CdS0.5, and Cu0.1ZnO0.9 catalysts. Using H2 as a reducing agent, the CO production rate over the ZnO0.45Cu0.1CdS0.45 catalyst reaches 770 μmol h-1 g-1, which is 3 and 1.8 times higher than those of ZnO0.5CdS0.5 and Cu0.1ZnO0.9 catalysts. Besides, the optimal CH4 production rate over ZnO0.45Cu0.1CdS0.45 reaches 890 μmol h-1 g-1. The improved photocatalytic response of the ZnO-Cu-CdS catalyst is assigned to the delayed recombination of photoexcited charge carriers through a Z-scheme charge transport mode, maintaining the photocarriers with strong redox potentials and the dual role of Cu to serve as a conductive bridge to accelerate the charge transfer rate and enhance the light absorption due to its SPR phenomenon. This research offers a promising strategy for developing binary/ternary Z-scheme heterojunction photocatalytic systems for different photocatalytic applications.