Photodegradation Of Methyl Orange Research Articles

Elimination of synthetic dyes by clamshell derived photo-active hydroxyapatite

Herein, a novel designed hydroxyapatite (HAp) derived from freshly calcined clamshell waste through the wet precipitation method was synthesized. HAp has been developed as a heterogeneous photocatalyst for the anionic dye methyl orange (MO) degradation. The pH on synthesizing HAp was varied in basic conditions. The results show HAp formed at pH more than 10. The MO photodegradation was done under UV-light irradiation for 120 min. HAp catalyst showed the optimum MO degradation efficiency using rod-like structure HAp synthesized at pH 12. HAp with optimum photodegradation efficiency was optimized for the catalyst loading and the pH of the MO solution. MO at pH 6 with 0.05 g catalyst loading showed the highest degradation efficiency around 97 % using HAp prepared at pH 12 with band gap at 4.990 eV. This finding brings a new insight on natural sources materials as photo-active in sustainable of persistent water pollutants.

Effect of vanadium doping on magnetic properties and photocatalytic activity of magnesium ferrite: Role of surface charge and dyes adsorption

Spinel magnesium ferrite nanoparticles play an important role in a variety of disciplines, particularly in environmental applications as magnetically separable photocatalysts. MgFe2-1.67xVxO4 with x = 0.0, 0.05, 0.10, and 0.20 were synthesized using the combustion method. X-ray diffraction (XRD) indicated that only the cubic spinel ferrite phase with the Fd3m space group was formed in all doped Mg-ferrite. The cell parameter increased at (x = 0.05) and thereafter dropped with increasing vanadium ion concentration. The saturation magnetization (Ms) increased from 26.181 to 28.953 with x = 0.05, then decreased with further doping. Additionally, the band gap energy (Eg) decreased with increasing v-doping; Eg for MgFe2O4 was 1.79 eV and decreased to 1.71 eV at x = 0.20. All the V-doped MgFe2O4 shows an increase in the efficiency of methyl orange photodegradation relative to undoped MgFe2O4. The boosting in photocatalytic activity of V-doped MgFe2O4 due to electron-hole separation, caused by oxygen vacancies. V-doping changes the point of zero charge of ferrite and increase the MO adsorption, consequently, enhances the photocatalytic degradation. V-doped MgFe2O4 has proved to be an effective magnetically separable and easily reusable photocatalyst withstand seven cycles of recyclability using MgFe2-1.67xVxO4 with x = 0.10, and only 4 % loss of its photocatalytic performance.

Utilizing waste corn straw to photodegrade methyl orange and methylene blue: Photothermal effect of biochar enhances photodegradation efficiency

The burning of corn straw will cause serious air pollution, and the utilization of corn straw can avoid the burning of corn straw and reduce environmental pollution. The pyrolysis of corn straw into biochar (BC) is a promising approach to apply corn straw in environmentally sustainable development. Dye wastewater such as methyl orange (MO) and methylene blue (MB) is a pollution that poses a threat to human health and the environment. Herein, biochar/TiO2 (BC/TiO2) and biochar/ZnO (BC/ZnO) were prepared by pyrolysis of corn straw for the photodegradation of MO and MB in water. The MO removal rates of BC/TiO2 and BC/ZnO are up to 83.3 % and 76.2 %, respectively, and the MB removal rates of BC/TiO2 and BC/ZnO are 78.6 % and 71.4 %, respectively. The photothermal effect of BC improves the surface temperature of photocatalysts and promotes the separation and transfer of photogenerated electron-hole pairs, enhancing the photodegradation of MO and MB efficiencies. Three-dimensional (3D) FDTD simulations were performed to investigate the mechanism of photothermal effect in BC/TiO2 and BC/ZnO. This work provides a promising approach to the utilization of corn straw.

Efficient Catalytic Degradation of Methyl Orange by Various ZnO-Doped Lignin-Based Carbons.

Herein, a series of ZnO-doped lignin-based carbons (LC/ZnO) were successfully prepared from different types of lignin and used for methyl orange (MO) photocatalytic degradation. The apparent morphology, internal structure, and photoelectric properties of prepared LC/ZnO composites and their effects on subsequent MO photocatalytic degradation were investigated by various characterization techniques. The results showed that the LC/ZnO composites that were prepared in this work mainly consisted of highly dispersed ZnO nanoparticles and lignin-based carbon nano-sheets, which were beneficial for subsequent photogenerated electrons and holes formation, dispersion, and migration. The MO could be significantly degraded with various ZnO-doped lignin-based carbons, especially over the LCSL/ZnO, and the maximum degradation rate was 96.9% within 30 min under the simulated 300w sunlight exposure. The experiments of free radical elimination showed that the photocatalytic degradation of MO over LC/ZnO were a result of the co-action of multiple free radicals, and h+ might play the predominant roles in MO degradation. In addition, the pH of the solution had little effect on MO degradation, and the MO could be effectively degraded even in an alkaline solution of pH = 12.0. The cycling experiments showed that the prepared LC/ZnO had a good stability for MO photodegradation, especially for LCSL/ZnO, even after 5 times recycling, and the degradation rate of MO only dropped from 97.0% to 93.0%. The research not only provided a fundamental theory for the efficient photocatalytic degradation of MO by LC/ZnO composites, but also offered a new insight into lignin valorization.

Refinement of Nanoporous Cu by Polyvinylpyrrolidone and Photodegradation of Methyl Orange by Cu2O Nanowires and Nanoporous Cu Photocatalysts

Refinement of nanoporous Cu (NP Cu) by the addition of Polyvinylpyrrolidone (PVP) in HF solution during dealloying of Ti40.6Zr9.4Cu40.6Ni6.3Sn3.1 amorphous ribbons and effect of the surface coverage of Cu2O nanowires obtained by immersing NP Cu in dehydrated ethanol on the photodegradation of methyl orange (MO) pollutants were investigated. The sizes of pores and ligaments of NP Cu decrease significantly with the increase of PVP concentration in the dealloying solutions, accompanied by a drastic decrease in the surface diffusivity and the dislocation defect densities. The surface coverage of Cu2O nanowires becomes higher with an increase of the PVP reagents. The Cu2O nanowires@nanoporous Cu (Cu2O@NP Cu) catalysts show excellent photocatalytic activity towards the degradation of MO under the sunlight due to the existence of large amounts of heterojunctions between Cu2O nanowires and Cu ligaments in nanoscale.

MgAl Oxide Coatings Modified with CeO2 Particles Formed by Plasma Electrolytic Oxidation of AZ31 Magnesium Alloy: Photoluminescent and Photocatalytic Properties

MgAl oxide coatings composed of MgO and MgAl2O4 phases were doped with CeO2 particles via plasma electrolytic oxidation (PEO) of AZ31 magnesium alloy in a 5 g/L NaAlO2 water solution. Subsequently, particles of CeO2 up to 8 g/L were added. Extensive investigations were conducted to examine the morphology, the chemical and phase compositions, and, most importantly, the photoluminescent (PL) properties and photocatalytic activity (PA) during the photodegradation of methyl orange. The number of CeO2 particles incorporated into MgAl oxide coatings depends on the concentration of CeO2 particles in the aluminate electrolyte. However, the CeO2 particles do not significantly affect the thickness, phase structure, or surface morphology of the coatings. The PL emission spectrum of MgAl oxide coatings is divided into two bands: one in the 350–600 nm range related to structural defects in MgO, and another much more intense band in the 600–775 nm range attributed to the F+ centres in MgAl2O4. The incorporated CeO2 particles do not have a significant effect on the PL intensity of the band in the red spectral region, but the PL intensity of the first band increases with the concentration of CeO2 particles. The PA of MgAl/CeO2 oxide coatings is higher than that of pure MgAl oxide coatings. The MgAl/CeO2 oxide coating developed in aluminate electrolyte with a concentration of 2 g/L CeO2 particles exhibited the highest PA. The MgAl/CeO2 oxide coatings remained chemically and physically stable across multiple cycles, indicating their potential for applications.

Increasing photocatalytic activity of magnetite NPs with the inclusion of methyl orange and Evans blue functional groups in the photoactivation of acid sites

In this paper, The photocatalytic reactions of methyl orange (MO) and Evans Blue (EB) are conducted on four distinct magnetite nanoparticles (NPs) samples. This study investigates, for the first time in literature, the impact of the inclusion of chromophores and auxochromes in the photoactivation of Brönsted and Lewis’s acid sites on the photocatalytic activity. In so doing, free functional groups of MO and EB that are not photodegraded have been analyzed using FTIR spectroscopy. This analysis leads to infer photoactivated acid site densities. FTIR analysis of initial residual solutions of MO and EB revealed lower contents of free functional groups of EB compared to MO. Based on this finding, it would be expected that EB would demonstrate better photodegradation due to the lower contents of its functional groups. However, the obtained results contradicted this assumption, indicating an opposite behavior. Moreover, FTIR analysis of final residual solutions revealed that functional groups of MO were highly photodegraded compared to EB. Also, calculated MO photodegradation capacities, yields, and kinetics constants were found to be higher than those of EB. This suggests that parameters other than band gap energy may control the photoactivation of Brönsted and Lewis’s acid sites and thus photocatalytic activity. Indeed, functional groups are involved in increasing the photocatalytic activity. The higher contents of MO functional groups lead to better increasing the photocatalytic activity of magnetite NPs.

Surface plasmon resonance and heterojunction formation in Ag/AgI/Ag3VO4 photocatalyst for efficient photodegradation of methyl orange

A novel Ag/AgI/Ag3VO4 plasmonic photocatalyst was synthesized through ion exchange technique, followed by photoreduction. Various techniques including X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and ultraviolet–visible diffuse reflection (UV-DRS) were undertaken to characterize the phase structure, morphology, chemical composition, and optical properties of Ag/AgI/Ag3VO4. The catalytic activity measurements were conducted using decomposing methyl orange (MO) irradiated with visible light. Compared with Ag/AgI and pure Ag3VO4, the Ag/AgI/Ag3VO4 composite significantly enhanced catalytic activity, resulting in 94.4% degradation of MO within 15 min of visible light. Ag/AgI/Ag3VO4 exhibited remarkable catalytic activity, which was because of the intimate heterojunction formation, and the surface plasmon resonance (SPR) effect of Ag nanoparticles (NPs), thereby boosting carrier separation. Furthermore, quenching tests confirmed that the majority of active species were •O2− and h+ during the catalytic reaction. This study discussed a plausible catalytic system mechanism that effectively separates photocreated carriers in the Ag/AgI/Ag3VO4 composite to enhance MO degradation activity.

Advanced Photodegradation of Azo Dye Methyl Orange Using H2O2-Activated Fe3O4@SiO2@ZnO Composite under UV Treatment.

The Fe3O4@SiO2@ZnO composite was synthesized via the simultaneous deposition of SiO2 and ZnO onto pre-prepared Fe3O4 nanoparticles. Physicochemical methods (TEM, EDXS, XRD, SEM, FTIR, PL, zeta potential measurements, and low-temperature nitrogen adsorption/desorption) revealed that the simultaneous deposition onto magnetite surfaces, up to 18 nm in size, results in the formation of an amorphous shell composed of a mixture of zinc and silicon oxides. This composite underwent modification to form Fe3O4@SiO2@ZnO*, achieved by activation with H2O2. The modified composite retained its structural integrity, but its surface groups underwent significant changes, exhibiting pronounced catalytic activity in the photodegradation of methyl orange under UV irradiation. It was capable of degrading 96% of this azo dye in 240 min, compared to the initial Fe3O4@SiO2@ZnO composite, which could remove only 11% under identical conditions. Fe3O4@SiO2@ZnO* demonstrated robust stability after three cycles of use in dye photodegradation. Furthermore, Fe3O4@SiO2@ZnO* exhibited decreased PL intensity, indicating an enhanced efficiency in electron-hole pair separation and a reduced recombination rate in the modified composite. The activation process diminishes the electron-hole (e-)/(h+) recombination and generates the potent oxidizing species, hydroxyl radicals (OH˙), on the photocatalyst surface, thereby playing a crucial role in the enhanced photodegradation efficiency of methyl orange with Fe3O4@SiO2@ZnO*.

Merits of photocatalytic activity of synthesized (ZnxCu(1−x)Fe2O4); x = (0–1) magnetic nanoparticles for wastewater treatment

Synthesis of crystalline zinc copper ferrite nanoparticles was achieved via a simple co-precipitation method. Scanning electron microscope (SEM) is utilized to give the morphological characterization of the prepared samples. A transmission electron microscope (TEM) was employed for further identification and confirmation of the particle size and morphology. Moreover, X-ray diffraction (XRD) and Fourier transformation infrared (FTIR) spectroscopy were utilized to examine crystalline structure and chemical structure, respectively. The photocatalytic performance of Zn0.5Cu0.5Fe2O4 nanoparticles under UV light was assessed by decolorization of methyl orange (MO) azo dye. The efficiency of photocatalytic degradation of 20 ppm of MO by Zn0.5Cu0.5Fe2O4 nanoparticles 15 mg was 96% after 135 min at an ambient temperature of 25 °C and pH value of 3. Further interpretation was carried out and a proposed mechanism for the MO photodegradation over Zn0.5Cu0.5Fe2O4 nanoparticles was suggested.

Novel ternary PPy–ZnFe2O4/fly ash-cenosphere photocatalysts for photodegradation of methyl orange under UV light

In this study, fly ash cenospheres (FACs), characterized by their floating properties and inherent photocatalytic activity, were used as a carrier to support ZnFe2O4 material and doped with conductive polymer polypyrrole (PPy) to prepare a novel ternary PPy–ZnFe2O4/FACs (PPy–ZF) composite catalyst. X-ray diffraction, Fourier transform infrared spectroscopy, TEM, and scanning electron microscopy were used to characterize the structure, morphology, and optical properties of the samples prepared. In particular, a 20 mg/L methyl orange (MO) solution at pH 4 was given 0.075 g of PPy–ZF catalyst to add, and after 30 min of dark adsorption, followed by irradiation for 180 min, 98.54% of the MO was removed. The material was also shown to have good stability and reusability through three cycles of use. Additionally, the material exhibited good photocatalytic activity for other dyes. The results of photocatalytic experiments showed their significantly enhanced photocatalytic activity toward MO, which was mainly attributed to the synergistic effect of PPy and ZnFe2O4 on the surface of FACs, leading to a high separation efficiency and a low rate of photogenerated charge complexation. In addition, cyclic tests demonstrated the stability and reusability of the composite. The leading role in the photocatalytic degradation of MO was demonstrated by the radical trapping experiment, which showed ·O2 − and h+. The present study can significantly improve the photocatalytic performance of the floating materials of ZnFe2O4/FACs, which is beneficial to solve the current energy crisis and environmental pollution problems. It has certain reference significance to solve the problems of environmental pollution, waste recycling, and catalyst recycling in the future.

Hydrophobic and Photocatalytic Treatment for the Conservation of Painted Lecce stone in Outdoor Conditions: A New Cleaning Approach

Self-cleaning and hydrophobic treatments based on TiO2 and SiO2 nanoparticles are widely applied for the preservation of cultural heritage materials, to improve their resilience in polluted environments. Excellent results have been obtained on stone materials, but experiments on painted stone surfaces, such as wall paintings and polychrome plasters used in historic buildings, are still limited. In this work, we present a study on the use of water dispersions of TiO2 nanoparticles obtained via sol-gel and organically modified silica (OrMoSil) for cleaning and protective purposes on Lecce stone, a carbonate stone, widely used for its excellent workability but easily attacked by atmospheric agents and pollutants. First, we evaluated the harmlessness of the treatment on Lecce stone through colorimetric tests, water absorption by capillarity and permeability to water vapor. The photocatalytic activity of the TiO2 nanoparticles was assessed by photo-degradation of methyl orange and methylene blue dyes. The dispersion was then applied on painted samples prepared according to ancient recipes to confirm the effectiveness of the cleaning. The proposed TiO2/OrMoSil-based coating can act as a self-cleaning and protective treatment on lithic surfaces to prevent degradation phenomena and preserve the original appearance of the monument.

Synthesis and application of ZSM-5/Graphene composite for photocatalytic degradation of industrial dyes

Various materials and technologies are being employed to address the concern of increased wastewater generation. In this work, the synthesis of ZSM-5 (Zeolite Socony Mobil-5) and graphene (GR) composite, their characterisation, and application for the removal of dyes are presented. Two composites of ZSM-5 and GR composites were prepared via the hydrothermal method by varying the loading amount of GR, i.e. 1% and 5%, and labelled as GZ1 and GZ5. The parent and composite materials were characterised using field emission scanning electron microscope (FE-SEM), x-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS), x-ray photoelectrons spectroscopy (XPS), Raman, and Fourier transform infrared (FTIR). The materials were then employed for the photodegradation of methyl orange (MO) dye. The adsorption efficiencies for ZSM-5, GR, GZ1, and GZ5 were found as 0%, 17.8%, 0%, and 16% respectively. According to photodegradation results, the GZ1 composite exhibits the maximum degradation efficiency of 75.3% for 20 ppm of MO, within 180 min of light exposure. The scavenger studies were performed to evaluate the role of active oxygen species (AOS) in the photocatalysis mechanism. All studies were performed with the catalyst dosage of 0.5 mg ml−1. The degradation efficiencies for GR, GZ5, and Z5 were reported as 34.2%, 20.8%, and 17.5%, respectively. On increasing the irradiation time to 240 min, the degradation efficiency of GZ1 reached 92%. The removal efficiencies for MO (7 ppm) and methyl blue (5 ppm) in a 12-ppm dye mixture were observed to be 98% and 97.2% respectively within 180 min of light exposure with GZ1 composite.

PH dependent synthesis of ceria nanoparticles for efficient sunlight-driven photocatalysis of methyl orange containing wastewater

In this study, cerium nitrate hexahydrate was used as a precursor to create nanocrystalline ceria nanoparticles, which were then created utilizing a simple and economical sol-gel method by adjusting the pH of the reactants between 6 and 12. Under direct sun radiation, wastewater containing methyl orange (MO) was photodegraded using the produced CeO2 NPs. For recent photocatalysis experiments, the degree of crystallinity, shape, dimensions, and degree of MO photodegradation were characterized and analyzed using XRD, FTIR, SEM, and UV–Vis spectrometry. According to the results, the pH of the synthesis solutions had a significant impact on the ceria-based photocatalysis of MO. Ceria NPs synthesized at a pH of 8 demonstrated optimal photocatalytic activity. Moreover, the results showed that variation in catalyst loading, initial concentration of MO, pH of MO-wastewater as well as exposure time have significantly impacted on photocatalytic performance of optimized CeO2. The optimum percentage degradation of around 75 % of MO was achieved in 80 min exposure of sunlight. Optimized low-cost ceria NPs prepared herein may be employed for dyes containing industrial wastewater treatment throughout the year using ordinary sunlight.

Boosting visible-light photodegradation of methyl orange and ibuprofen over rGO-supported Ag3PO4 nanocomposite

A novel rGO/Ag3PO4 nanocomposites were synthesized using a straightforward precipitation method. The as-prepared rGO/Ag3PO4 nanocomposites were thoroughly characterized through different tools, and their catalytic activity for the decomposition of ibuprofen (IBU) antibiotic plus methyl orange (MO) dye was studied for the first time. The outcomes revealed the successful preparation of modified Ag3PO4. The rGO/Ag3PO4 nanocomposite exhibited exceptional photodegradation efficiency for MO dye (97 % removal in 90 min) and IBU antibiotic (90.3 % elimination in 240 min) displaying a rate constant of 0.0295, and 0.0085 min−1, respectively, under visible light illumination. The catalytic efficacy was optimized in degradation studies by changing variables like catalyst dose and solution pH. Radical scavenger studies have validated the impact of reactive species in antibiotic and dye decomposition. The holes were essential in photocatalytic decomposition. Furthermore, the photocatalyst can be recycled four times without losing much activity. Finally, the mechanism for the catalyst's photodegradation was proposed.

Emergence of S-scheme-derived Ag decorated CuBi2O4/CNTs/(BiO)2CO3 photocatalyst with enhanced visible light photocatalytic performance

BackgroundDue to advantages like low cost, and high catalytic efficiency, photocatalysis has attracted more and more attention. The present investigation presents a straightforward and cost-effective hydrothermal method for producing Ag-decorated CuBi2O4/CNTs/(BiO)2CO3 composites with varying weight percentages of (BiO)2CO3. MethodsHerein, systematic investigations were conducted to examine the crystal, morphological, and optical properties of the photocatalysts. The investigation focused on evaluating the photocatalytic performance via visible light-assisted photodegradation of methyl orange (MO) and rhodamine B (RhB). Significant findingsFindings revealed that loading of (BiO)2CO3 efficiently improved the photoactivity of the composite. The Ag-CuBi2O4/CNTs/(BiO)2CO3 heterojunction photocatalyst with 15 % loading of (BiO)2CO3 has expressively enhanced photocatalytic performance, estimated around 97.79 % of RhB and 98.29 % of MO photo-degraded within 70 min in visible light irradiation, which was also found much enhanced than that of bare CuBi2O4 and (BiO)2CO3. Re-cyclic experiments indicated that fabricated semiconductor hybrid photo-catalyst own good photo-stability as well as reusability. The involvement of ∙O2- and ∙OH active radical species in the process of increased photo-degradation has been demonstrated using ESR and radical trapping tests. The description of the full photocatalytic mechanism based on the S-scheme was conducted by considering the estimated energy band locations, electron spin resonance (ESR) analysis and reactive oxygen species (ROS) trapping tests. This study presents a pragmatic methodology for the development of wide-bandgap bismuth-derived semiconductors that exhibit effective photo-degradation for environmental remediation.

An efficient polymer supported Fenton type catalyst for photodegradation of organic dyes

The catalytic potential of a novel polymer-supported iron complex (mPAN-Fe) prepared by immobilizing FeCl3 on hydrazine modified polyacrylonitrile (mPAN) is evaluated for the degradation of organic dyes. The prepared complex was characterized using FTIR, XRD, SEM, ICP-MS and DRS/UV analyses. It was found that this complex can acts as an effective heterogeneous catalyst for the photodegradation of methylene blue, methyl orange, and Rhodamine-6G in presence of hydrogen peroxide as an oxidant. The effects of reaction parameters such as concentration of the catalyst, concentration of oxidant, concentration of the dye and pH of the medium on the photodegradation of methylene blue were also studied. The photodegradation of methylene blue was found to be 99 % within 70 min. Moreover, this catalyst exhibited excellent reusability up to 6 cycles for photocatalytic degradation under optimised conditions without significantly losing its activity. The catalyst was also found to be effective for the photodegrdation of methyl orange and Rhodamine-6G. A possible mechanism of photocatalysis under the reaction conditions has been proposed. This is the first study involving a hydrazine-modified PAN-supported iron catalyst towards greener and efficient photocatalysis.

Vesicular BiVO4 nanostructures modified by g-C3N4 quantum dots for enhanced photocatalytic activity

Photocatalysis technology has been an available method to alleviate the improper discharge of dye wastewater by employing light energy to degrade the dye pollutants. Here, the vesicular BiVO4 hollow structures were modified by graphite phase carbon nitride quantum dots (CNQDs) to construct the BiVO4-based photocatalyst (BiVO4/CNQDs) for the enhanced removal of dye molecules. The CNQDs with a diameter of 2–5 nm evenly decorate on BiVO4 vesicles to construct the close interface of the BiVO4/CNQDs heterojunctions. Compared with vesicular BiVO4, the enhanced visible-light decomposition of methyl orange (MO) comes down to the coordination of different components, the C and/or N doping and hollow structure. This is helpful to increase surface area of bulk BiVO4, broaden light response, narrow band gap and obstruct charge combination. Especially, the up-conversion luminescence of the CNQDs can induce BiVO4 to generate more photo-excited electrons to participate in the MO photo-degradation reaction. The BiVO4/CNQDs heterojunctions with the unique hollow structure and excellent photocatalytic activity display the promising utilization in wastewater treatment.

Influence of production method on the structure and photocatalytic activity of CeO<sub>2</sub>/Au nanocomposite

Two methods for preparing mesoporous CeO2/Au nanocomposites were compared: template synthesis and photochemical modification of fibrous cerium(IV) oxide with gold nanoparticles. The composition, structure, morphology of the obtained nanocomposites, as well as the specific surface area and pore size distribution were studied by a complex of physicochemical methods: X-ray phase analysis, X-ray spectral microanalysis, scanning electron microscopy, low-temperature nitrogen adsorption, and electron spectroscopy. The catalytic properties of the obtained nanocomposites were studied in methyl orange photodegradation reactions. It is shown that the CeO2/Au catalyst obtained by the photochemical modification method has the highest photocatalytic activity both under the action of UV and visible light.

Composites of W18O49 Nanowires with g-C3N4/RGO Nanosheets for Broadband Light-Driven Photocatalytic Wastewater Purification.

Developing a photocatalyst that can effectively utilize the full solar spectrum remains a high-priority objective in the ongoing pursuit of efficient light-to-chemical energy conversion. Herein, the ternary nanocomposite g-C3N4/RGO/W18O49 (CN/RGO/WO) was constructed and characterized by a variety of techniques. Remarkably, under the excitation of photon energies ranging from the ultraviolet (UV) to the near-infrared (NIR) region, the photocatalytic performance of the CN/RGO/WO nanocomposite exhibited a significant enhancement compared with single component g-C3N4 or W18O49 nanosheets for the degradation of methyl orange (MO). The MO photodegradation rate of the optimal CN/1.0 wt% RGO/45.0 wt% WO catalyst reached 0.816 and 0.027 min-1 under UV and visible light excitation, respectively. Even under low-energy NIR light, which is not sufficient to excite g-C3N4, the MO degradation rate can still reach 0.0367 h-1, exhibiting a significant enhancement than pure W18O49. The outstanding MO removal rate and stability were demonstrated by CN/RGO/WO nanocomposites, which arise from the synergistic effect of localized surface plasmon resonance effect induced by W18O49 under vis-NIR excitation and the Z-scheme nanoheterojunction of W18O49 and g-C3N4. In this work, we have exploited the great potential of integrating nonmetallic plasmonic nanomaterials and good conductor RGO to construct high-performance g-C3N4-based full-solar spectral broadband photocatalysts.