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Bismuth-based photocatalytic materials have been widely used in the field of photocatalysis in recent years due to their unique layered structure. However, single bismuth-based photocatalytic materials are greatly limited in their photocatalytic performance due to their poor response to visible light and easy recombination of photogenerated charges. At present, constructing semiconductor heterojunctions is an effective modification method that improves quantum efficiency by promoting the separation of photogenerated electrons and holes. In this study, the successful preparation of an In2O3/Bi2WO6 (In2O3/BWO) II-type semiconductor heterojunction composite material was achieved. XRD characterization was performed to conduct a phase analysis of the samples, SEM and TEM characterization for a morphology analysis of the samples, and DRS and XPS testing for optical property and elemental valence state analyses of the samples. In the II-type semiconductor junction system, photogenerated electrons (e−) on the In2O3 conduction band (CB) migrate to the BWO CB, while holes (h+) on the BWO valence band (VB) transfer to the In2O3 VB, promoting the separation of photoinduced charges, raising the quantum efficiency. When the molar ratio of In2O3/BWO is 2:6, the photocatalytic degradation degree of rhodamine B (RhB) is 59.4% (44.0% for BWO) after 60 min illumination, showing the best photocatalytic activity. After four cycles, the degradation degree of the sample was 54.3%, which is 91.4% of that of the first photocatalytic degradation experiment, indicating that the sample has good reusability. The XRD results of 2:6 In2O3/BWO before and after the cyclic experiments show that the positions and intensities of its diffraction peaks did not change significantly, indicating excellent structural stability. The active species experiment results imply that h+ is the primary species. Additionally, this study proposes a mechanism for the separation, migration, and photocatalysis of photoinduced charges in II-type semiconductor junctions. [ABSTRACT FROM AUTHOR]

The auto-combustion method synthesized CuO NPs and Ag/CuO NPs. The Ag/CuO NPs were analyzed using Fourier-transform infrared, X-ray diffraction, scanning electron microscope, and Energy-dispersive X-ray spectroscopy instrumental analyses. The energy band gap, as determined by DRS properties, decreases from 3.82 to 3.50 eV for pure CuO and 10% Ag/CuO NPs, respectively. The photodegradation efficiency of Rhodamine-B & Carmine by 10% Ag/CuO NPs was nearly 98.9 and 97.8%, respectively. Antimicrobial trials revealed that the antimicrobial efficacy of Ag/CuO NPs at several dosages (20, 40, 60, 80, 100, and 120 µg/mL) against human pathogens was initially assessed using the agar well-diffusion method, and then the broth dilution method. Noticeably, the minimum inhibitory concentration of Ag/CuO NPs for all pathogens ranged from 100 to 120 µg/ml, was determined. Generally, the observed minimum microbicide concentration has a wide range of Ag/CuO NPs doses, ranging from 150 to 300 µg/ml, which helps kill (99.99%) all tested pathogenic cells. The largest relative inhibitory activities (%) were recorded against Escherichia coli (81.45 ± 1.39) at 120 g/mL of Ag/CuO NPs and 100 μg/mL (80.43 ± 0.59), followed by 80 µg/mL (72.33 ± 0.82). Additionally, the lowest relative inhibitory activities (%) were monitored versus fungal cells and Gram-positive bacteria at 120 µg/mL of Ag/CuO NPs as 52.17 ± 1.49 and 53.42 ± 1.71; respectively. [ABSTRACT FROM AUTHOR]

Photocatalysis is a promising method for methylene blue (MB) degradation due to its effectiveness and environmental compatibility. Among the photocatalysts, titanium dioxide (TiO2) has been widely used for MB degradation due to its exceptional photocatalytic activity. However, the wide bandgap limits the degradation efficiency of TiO2 under visible light. Here, an interstitial nitrogen-doped TiO2 (5%NT/TiO2) used thiourea as the N source was fabricated for visible light-derived MB degradation. The 5%NT/TiO2 exhibited an extended absorption range of visible light. Moreover, photoelectrochemical measurements showed an improvement in the photocurrent response and charge transfer behavior on N/TiO2. Thus, 5%NT/TiO2 had enhanced photocatalytic activity compared with pristine TiO2 and substitutive N-doped TiO2 (5%NAB/TiO2). The accelerated photocatalytic MB degradation process on N/TiO2 could be mainly attributed to the interstitial N doping, which caused the appearance of new energy states and extended optical properties. Through comparing the impact of interstitial and substitutive in TiO2 activity, our work proposes a suitable form of element doping to enhance the optical properties and photocatalytic activity of TiO2 and even other semiconductors, providing guidance for future work. [ABSTRACT FROM AUTHOR]

Synthesis of ternary nanocomposites of BiFeO 3 -Graphene-KNbO 3 through simple solution method has been made at various concentrations of graphene ranging 0.025–0.1 % mole fraction. The obtained nanocomposite powders with varying content of graphitic phase were subjected to different characterization techniques such as XRD, Raman, SEM/EDX/Elemental mapping, HR-TEM, UV–Vis–NIR spectroscopy, dielectric and photodegradation measurements. All above studies have provided the collective impression of the existence of all entities in the prepared ternary composites. Dielectric studies revealed that progressive loading of graphene content led to the increased pathway for the conduction of electrons in the sample. However, the loading of graphene at appropriate concentration has brought out increased dye degradation capacity of BiFeO 3 -Graphene-KNbO 3 ternary nanocomposites towards methylene blue dye. The results obtained from various studies have been discussed in detail. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) nanotubes were obtained by the anodization process, applying a potential of 30 V for 2 h in an electrolyte composed of NH4F, H2O and ethylene glycol. The nitrogen doping of the obtained nanostructures was studied and the influence of the use of different temperatures during the thermal treatments 400, 500 and 600°C, on the formed nanotubes were evaluated. The morphology and crystalline structure of the obtained materials were determined by field emission gun scanning electron microscopy and X-ray diffraction. The optical properties were evaluated by UV–Vis diffuse reflectance spectroscopy and the photoelectrochemical properties by linear sweep voltammetry curves. The photocatalytic activity of nanotubes was evaluated by degradation of glycerol in aqueous medium using UV and visible radiation. TiO2 nanotubes developed photoactivity, photoelectrochemical behaviour and presented catalytic activity for glycerol degradation, which is more evident with UV radiation. The sample thermally treated at 500°C was the one that presented superior photoelectrochemical behaviour and superior photocatalytic activity when exposed to both UV and visible radiation. [ABSTRACT FROM AUTHOR]

Abstract The auto-combustion method synthesized CuO NPs and Ag/CuO NPs. The Ag/CuO NPs were analyzed using Fourier-transform infrared, X-ray diffraction, scanning electron microscope, and Energy-dispersive X-ray spectroscopy instrumental analyses. The energy band gap, as determined by DRS properties, decreases from 3.82 to 3.50 eV for pure CuO and 10% Ag/CuO NPs, respectively. The photodegradation efficiency of Rhodamine-B & Carmine by 10% Ag/CuO NPs was nearly 98.9 and 97.8%, respectively. Antimicrobial trials revealed that the antimicrobial efficacy of Ag/CuO NPs at several dosages (20, 40, 60, 80, 100, and 120 µg/mL) against human pathogens was initially assessed using the agar well-diffusion method, and then the broth dilution method. Noticeably, the minimum inhibitory concentration of Ag/CuO NPs for all pathogens ranged from 100 to 120 µg/ml, was determined. Generally, the observed minimum microbicide concentration has a wide range of Ag/CuO NPs doses, ranging from 150 to 300 µg/ml, which helps kill (99.99%) all tested pathogenic cells. The largest relative inhibitory activities (%) were recorded against Escherichia coli (81.45 ± 1.39) at 120 g/mL of Ag/CuO NPs and 100 μg/mL (80.43 ± 0.59), followed by 80 µg/mL (72.33 ± 0.82). Additionally, the lowest relative inhibitory activities (%) were monitored versus fungal cells and Gram-positive bacteria at 120 µg/mL of Ag/CuO NPs as 52.17 ± 1.49 and 53.42 ± 1.71; respectively. Graphic abstract

The BixOyIz and CoFe2O4 combination enhances photocatalytic degradation of tetracyclines (TCs). Three TC antibiotics including TC, oxytetracycline (OTC), and chlortetracycline (CTC) with high concentration (50 mg L−1) were utilized as target pollutant. Bi5O7I/Bi4O5I2, with its Z‐scheme, improves removal efficiency to 1.6 times that of Bi5O7I and 1.4 times that of Bi4O5I2. Ternary Bi5O7I/Bi4O5I2/CoFe2O4 (I/I/Co) composites further increase efficiency, with I/I/Co‐2 achieving 1.6 times that of I/I‐2. The improved performance is due to an optimized microstructure, which promotes light absorption and carrier transfer. CoFe2O4 nanoparticles on nanosheets create a double‐Z band structure, enhancing redox activity. Radical trapping experiments indicated the major active species (•O2−, OH−, and h+) in photocatalytic process of I/I/Co‐2. Based on their enhanced removal efficiencies for high‐concentration TCs, proper magnetic separation capacity, and recycling performance, the practical applications of I/I/Co composites to treat real TC wastewater might be implemented. [ABSTRACT FROM AUTHOR]

In this study, a series of submicron‐sized functional polymer particles poly(Sty‐co‐MAA) with variable methacrylic acid (MAA) content were prepared by soap‐free emulsion polymerization of styrene (Sty), methacrylic acid (MAA), and ethylene glycol dimethacrylate (EGDMA). The number‐average diameters of polymer particles (Dn) were in the range of 0.11 to 0.19 μm. A decrease in particle size was observed with increasing the molar ratio of MAA comonomer in the recipe. ZnO/poly(Sty‐co‐MAA) hybrid polymer particles were prepared by seeded emulsion copolymerization in presence of zinc oxide nanoparticles (ZnO NPs) as seed particles synthesized using Citrus lemon aqueous leaf extract. Scanning electron microscopy (SEM), transmission electron microsphere (TEM), X‐Ray Diffraction (XRD), and Fourier transformed infra‐red (FT‐IR) analysis were performed to characterize polymer particles. The crystalline size of ZnO NPs and ZnO/poly(Sty‐co‐MAA) hybrid polymer particles calculated from XRD analysis were 20.75 and 29.85 nm, respectively. These hybrid polymer particles were applied as photocatalyst in the photodegradation of methylene blue (MB) dye under UV irradiation, which showed high catalytic activity with degradation efficiency of 85.70 % at room temperature compared to bare ZnO NPs. [ABSTRACT FROM AUTHOR]

Herein, we investigate the photocatalytic properties of a new Ag2MoO4/CuWO4 composite. Three different composites with 5, 10, and 15 weight percent of fine Ag2MoO4 nanostructures were precipitated on CuWO4 nanoparticles. Given the staggered valence and conduction band positions of the two components, the composite with the 10 % weight percent Ag2MoO4 loading on CuWO4 demonstrated the slowest recombination kinetics. The same composite also exhibited the best photocatalytic degradation of RhB under UV light irradiation. The photocatalytic turnover frequency of this composite was also among the best reported for RhB degradation reported in the literature. Photocatalytic kinetics, active species trapping, and various control experiments were carried out to get an insight into the photocatalytic mechanism. The optimum photocatalyst exhibited its highest activity at pH 3 and a RhB degradation turnover frequency (photocatalytic activity) comparable to the best values reported in the literature. [ABSTRACT FROM AUTHOR]

In this research, nickel oxide (NiO) peculiar nanosheets with a thickness of less than 50 nm were produced via a low-cost, one-step, safe hydrothermal process. The reaction was conducted with two concentrations of Ni (NO 3 ) 2 ⋅ 6H2O (0.01 and 0.03) at 120 ∘ C for 3 h. Methylene Blue (MB) dye was used to examine the photoactivity of NiO nanosheet films under sunlight. The prepared NiO nanosheet films were evaluated using XRD, FE-SEM, EDX and UV-visible techniques. Accordingly, (FE-SEM) images confirm that the films synthesized by a hydrothermal method were flower-like nanosheets with a diameter of 33.4–52.7 nm, and the thickness of the NiO film is about 3.629 μ m. The average particle size and crystalline structures were estimated using XRD Analysis. However, both films were then exposed to direct sunshine for 80 min. The respective photocatalytic efficiencies of films were calculated to be 85% and 88%. The effectiveness of the photocatalytic degradation for eliminating Methylene Blue (MB) depends on the concentration, proving that the efficiency can be improved by increasing the concentration. [ABSTRACT FROM AUTHOR]

Biotreatment of wastewater has attracted considerable attention due to its low cost and eco-friendliness. This study developed a novel bionanocomposite comprised of Nanochitosan (NCS), Bentonite (Bt), and SnO2–ZnO nanocomposite prepared using Salvia officinalis extract as a reducing/stabilizing agent. The NCS/Bt/SnO2–ZnO bionanocomposite exhibited a rough surface with porous nature. EDX, XRD, and FTIR results confirmed the formation of the bionanocomposite. TGA indicated high thermal stability of the NCS/Bt/SnO2–ZnO. DRS results revealed that the bionanocomposite had a band gap of 2.60 eV. The surface area of NCS/Bt/SnO2–ZnO was found to be 32.54 m2 g−1 with a 17.98 nm pore size. Adsorption of Fe(III) and Pb(II) ions and photocatalytic degradation of methylene blue (MB) dye using this bionanocomposite were studied. Under optimal conditions, the highest removal of Fe(III) (99.5%) and Pb(II) (91.5%) was achieved after 5 min and 40 min, respectively. The adsorption data fitted the Langmuir isotherm and indicated the removal capacity of 555.55 and 243.90 mgg−1 for Fe(III) and Pb(II), respectively. Also, the NCS/Bt/SnO2–ZnO showed the MB dye degradation efficiency of 99% within 30 min. Therefore, the NCS/Bt/SnO2–ZnO can be used as an environmentally friendly, cost-effective, thermally stable, and high-performance adsorbent/photocatalyst to remove heavy metal ions and dye molecules. [ABSTRACT FROM AUTHOR]

PEO coatings are formed by subjecting a metal substrate to an electrolytic plasma discharge, resulting in the formation of a porous and rough oxide layer. Herein, the significant role of the chemical composition of the electrolyte system and additives in the formation of an oxide coating on brass alloy in the PEO process was investigated. It was observed that the coating created with 8 g/l aluminate, 1 g/l NaOH, and 1 g/l KF electrolyte had higher homogeneity than other coatings. This is because a composite oxide coating of Cu 2 O, ZnO, and AlCuO 2 was formed. Methylene Blue (MB), a widely used dye in various industries, is known to be persistent and environmentally harmful. The photocatalytic activity of the PEO coating on brass for the removal of MB was investigated under visible light exposure. According to the results, the presence of the sample produced in an electrolyte containing 8 g/l Aluminate, 1 g/l NaOH, and 1 g/l KF resulted in a degradation rate of approximately 65 % for MB photodegradation after 6 h of irradiation. The PEO-coated brass shows promising photocatalytic efficiency compared to our research group's PEO-coated TiO 2 coatings, indicating its potential as a photocatalyst. The results highlight that PEO coating on brass could be a potential candidate for photocatalytic and photoelectrochemical applications. [ABSTRACT FROM AUTHOR]

In this investigation, we employed a straightforward hydrothermal method to synthesize various TiO2 nanostructures, including titanium nanoparticles (TNPs), titanium nanorods (TNRs), and titanium nanotubes (TNTs). Generally, TiO2 is a widely studied chemical compound in the materials research field, which finds applications in diverse areas such as photocatalysis and energy storage systems. Furthermore, these nanostructures hold immense potential for applications in dye degradation and supercapacitors. To characterize the synthesized photocatalysts, we employed techniques such as XRD, DLS, UV–Vis spectra, SEM, TEM, and electrochemical workstation. The as-synthesized photocatalysts demonstrated remarkable efficiency in degrading different concentrations of rhodamine B (RhB) and methyl orange (MO) dyes under direct sunlight while also exhibiting excellent electrochemical properties. For comparison, we included bulk TiO2 anatase powder in our study. In the case of supercapacitor application, TNRs exhibited the highest specific capacitance of 122 F g−1 at a current density of 0.5 A g−1, outperforming the 0-dimensional (0D) nanostructures and bulk TiO2 powder (TBP). Our results indicate that the 1-dimensional (1D) TiO2 nanostructures offer superior performance under optimal experimental conditions compared to the other forms of TiO2. [ABSTRACT FROM AUTHOR]

This study investigates the influence of various anodic oxidation parameters on the photocatalytic activities of the nanostructured titanium dioxide (TiO2) films. TiO2 films were prepared by anodic oxidation of titanium substrate using 1 M Na2SO4 / 5 wt. % NH4F electrolyte, and then annealed at 500 °C. Anatase appears in all calcined samples. The anodic oxidation process was performed in two steps at different voltages (5–80 V) and times (15–480 min) to reveal the relationship between the surface morphologies, wettability and photocatalytic properties. The results showed that the voltage and anodization time can play important role in the surface morphology of nanostructured TiO2 films and thus in various properties. While 40 V showed the most efficient photocatalytic degradation among voltage values, 60 min was the most efficient time for photocatalytic degradation efficiency and lowest contact angle. In addition, a pore area fraction of 39.54%, equal diameter of 96.81 nm, and circularity of 66.7% were obtained from image analysis of the 60-min anodized sample. While increasing the voltage and time benefited up to a point in terms of photocatalytic efficiency, changes in morphology had a negative effect after a point. At low voltage and time values, small pore diameters result in low photocatalytic properties. This titania can be readily utilize to meet application expectations in areas such as gas sensors, photocatalysis and photovoltaic cells. [ABSTRACT FROM AUTHOR]

This work successfully demonstrates a sustainable and environmentally friendly approach for synthesizing Semal-ZnO nanoparticles (NPs) using the aqueous leaf extract of Bombax ceiba L. These NPs exhibit an absorption peak at approximately 390 nm in the UV-visible spectrum and an energygap (Eg) of 3.11 eV. Detailed analyses of the morphology and particle size using various spectroscopic and microscopic techniques, XRD, FE-SEM with EDS, and HR-TEM reveal crystallographic peaks attributable to the hexagonal phase, with an average crystal size of 17 nm. The Semal-ZnO NPs also exhibit a notable photocatalytic efficiency for degrading methylene blue (MB) and methyl orange (MO) under sunlight in different water samples collected from diverse natural sources, indicating that they are promising photocatalysts for environmental remediation. The photocatalytic efficiency of the biofabricated Semal-ZnO NPs is impressive, exhibiting a photodegradation rate of up to 99% for MB and 79% for MO in different water samples under exposure to sunlight. The novel phytofabricated Semal-ZnO NPs are thus a beacon of hope for the environment, with their desirable photocatalytic efficiency, pseudo-first-order kinetics, and ability to break down noxious dye pollutants in various aquatic environments. [ABSTRACT FROM AUTHOR]

In this study, a Ti3C2 MXene@g-C3N4 composite powder (TM-CN) was prepared by the ultrasonic self-assembly method and then loaded onto a carbon nanofiber membrane by the self-assembly properties of MXene for the treatment of organic pollutants in wastewater. The characterization of the TM-CN and the C-TM-CN was conducted via X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectrometer (FTIR) to ascertain the successful modification. The organic dye degradation experiments demonstrated that introducing an appropriate amount of Ti3C2 MXene resulted in the complete degradation of RhB within 60 min, three times the photocatalytic efficiency of a pure g-C3N4. The C-TM-CN exhibited the stable and outstanding photocatalytic degradation of the RhB solution over a wide range of pH values, indicating the characteristics of the photodegradation of organic pollutants in a wide range of aqueous environments. Furthermore, the results of the cyclic degradation experiments demonstrated that the C-TM-CN composite film maintained a degradation efficiency of over 85% after five cycles, thereby confirming a notable improvement in its cyclic stability. Consequently, the C-TM-CN composite film exhibits excellent photocatalytic performance and is readily recyclable, making it an auspicious eco-friendly material in water environment remediation. [ABSTRACT FROM AUTHOR]

Copper oxide nanoparticles (CuO NPs) were synthesized using mucilage from the seeds of Mimosa pudica. Fully characterized CuO NPs using different spectroscopic techniques, such as UV-Vis, XRD, SEM, and FTIR, were evaluated as catalysts for the photodegradation of methyl orange and methylene blue. The UV-Vis analysis displayed an intense surface plasmon resonance at 273 nm, indicating the formation of CuO NPs. The functional groups in the mucilage and synthesized CuO NPs were examined by FTIR spectroscopy, and a peak at 475 cm-1 established the successful synthesis of CuO NPs. The morphology of the CuO NPs was observed by SEM analysis, revealing spherical CuO NPs embedded in the mucilage. The crystalline nature of CuO NPs was confirmed by XRD analysis, which showed a mean crystallite size of 29 nm. Furthermore, following pseudo-first-order kinetics, CuO NPs degraded methylene blue (89.47%) more effectively than methyl orange (79.25%) under sunlight. The reusability of CuO NPs was studied, and, after 4 cycles, CuO NPs indicated excellent photocatalytic performance with minor decrease in efficiency. [ABSTRACT FROM AUTHOR]

Water is a vital ingredient for life, but its quality is constantly deteriorating due to textile effluent carrying harmful dyes. Photodegradation is a highly effective process for breaking down dye using solar spectrum. In the current work, hydrothermal approach was used to designed pure tungsten disulfide and doped tungsten disulfide with differnet concentration (5, 10, and 15%) for photocatalytic degradation of methylene voilet. Different instrumental analyses were conducted to measure the physichemical and optical properties of the fabricated pure and doped materials. The photocatalytic behavior of the WS2, 5% doped WS2, 10% doped WS2 and 15% doped WS2 was noted after 0, 15, 30, 45, 60, and 75 min under sunlight. The removal of methyl violet (MV) by using pristine WS2, 5% doped WS2, 10% doped WS2 was about 51, 70, and 80%, respectively. The maximum degradation of methylene violet was given by 15% doped WS2 about 90% after 75 min under sunlight. The 15% doping of the Sm reduced the band gap that can effectively absorb the greater extent of the solar spectrum and degrade the methyl violet dye. The fabricated optimized doped photocatalyst can also be employed in other application such as batteries, drug delivery, and water splitting. [ABSTRACT FROM AUTHOR]

Sn doped and BiOI coupled dual modified Bi2WO6 photocatalytic material was prepared using hydrothermal route. The phase composition, morphology, surface area, elemental composition and oxidation state, as well as optical properties, were comprehensively characterized. Take the methylene blue (MB) as the model pollutant for photodegradation to estimate the photocatalytic property of the synthesized material. The prepared Bi2WO6- based composite material shows a flower-like structure assembled from nanosheets, with a surface area of 45.3 m²/g and a bandgap width of 2.41 eV, enabling visible light responsiveness. The synergistic effect of Sn doping and BiOI coupling modification enhances the photocatalytic performance. The Sn-BiOI/Bi2WO6 photocatalytic composite material shows excellent photocatalytic activity, with complete degradation of MB after 40 minutes of illumination, and a first-order reaction rate constant (k) of 0.102 min-1. Experimental evidence suggests that photoinduced holes are the main active species. [ABSTRACT FROM AUTHOR]

Green synthesis of gold nanoparticles (AuNPs) is gaining attention of researchers because of their varieties of biomedical and environmental applications. This study reported the novel eco-friendly synthesis of AuNPs using green macroalgae Halimeda macroloba (HM) extract and evaluate their photocatalytic potential. The green synthesized H. macroloba mediated gold nanoparticles (HM-AuNPs) was characterized using UV-visible spectrophotometry, Fourier-transform infrared (FT-IR) spectroscopy, transmission electron microscope (TEM), scanning electron microscope-energy dispersive spectroscopy, x-ray photoelectron spectroscopy (XPS), and particle size distribution (PSD) anlaysis. The UV-visible spectrum shows a sharp intense plasmonic resonance peak at 543 nm. The bioactive compounds present in HM were primarily responsible for the biological reduction of gold ions validated by FT-IR analysis. XRD analysis proved the crystalline face centered cubic structure of the HM-AuNPs. The average particle size of 18.72 nm and morphological evidences were obtained from the images from TEM. The metallic form of biosynthesised HM-AuNPs was confirmed by XPS results with a distinctive binding energy. The photocatalytic degradation ability of the green synthesized HM-AuNPs was investigated against the methylene blue (MB) and methylene orange (MO) dyes under sunlight irradiation. The HM-AuNPs exhibited 97.23% and 89.91% photocatalytic activity against MB and MO after 90 min of exposure to sunlight, respectively. The overall results of this research indicate that H. macroloba mediated HM-AuNPs can be used as an effective option for the degradation of industrial dyes. [ABSTRACT FROM AUTHOR]

The inherent properties of TiO2, including a wide band gap and restricted spectral response range, hinder its commercial application and its ability to harness only 2–3% of solar energy. To address these challenges and unlock TiO2's full potential in photocatalysis, C60- and CdS-co-modified nano-titanium dioxide has been adopted in this work to reduce the band gap, extend the absorption wavelength, and control photogenerated carrier recombination, thereby enhancing TiO2's light-energy-harnessing capabilities and hydrogen evolution capacity. Using the sol-gel method, we successfully synthesized CdS-C60/TiO2 composite nanomaterials, harnessing the unique strengths of CdS and C60. The results showed a remarkable average yield of 34.025 μmol/h for TiO2 co-modified with CdS and C60, representing a substantial 17-fold increase compared to pure CdS. Simultaneously, the average hydrogen generation of C60-modified CdS surged to 5.648 μmol/h, a notable two-fold improvement over pure CdS. This work opens up a new avenue for the substantial improvement of both the photocatalytic degradation efficiency and hydrogen evolution capacity, offering promise of a brighter future in photocatalysis research. [ABSTRACT FROM AUTHOR]

This study presents a novel approach to address synthetic dye pollution in wastewater by introducing a novel ZnO/CuO/Cu2MgO3 nanocomposite (NC) synthesized using a green method involving Common Rue plant extract. Through a series of meticulous experimental procedures, the synthesized materials exhibited remarkable properties. The ZnO/CuO/Cu2MgO3 NC exhibits a moderate band gap energy of 1.5 eV, confirming its semiconductor nature. XRD analysis revealed crystallite sizes of 29 nm. FTIR analysis provided insights into chemical compositions. SEM reveals well-defined, spherical nanocomposite particles. The research aims to investigate the photocatalytic degradation efficiency of this nanocomposite, with a focus on removing Bromocresol Green (BCG), a recalcitrant synthetic dye in wastewater. Photocatalytic degradation experiments demonstrate an impressive 99.66% BCG removal efficiency through adsorption within 75 min of solar irradiation with a rate constant of 0.091 min−1. The nanocomposites exhibited excellent recyclability, maintaining their photocatalytic activity over five consecutive cycles. This study introduces an eco-friendly nanocomposite and synthesis approach, offering a rapid and efficient solution for BCG degradation and addressing the challenges posed by synthetic dye pollutants in wastewater. [ABSTRACT FROM AUTHOR]

Metallurgical solid waste blast furnace water quenched slag (WBFS) was employed as carrier materials to prepare Fe–TiO 2 /WBFS composite photocatalyst using a sol-gel method for improving both the photocatalytic activity and the high-value utilization of metallurgical solid waste. The Fe3+ doping technology was adopted to increase the utilization of solar energy. The influencing factors and photocatalytic activity were systematically evaluated by thermogravimetry/differential thermal analyser (TG-DSC), X-Ray Diffraction (XRD), Brunauer-Emmett-Teller (BET) method, scanning electron microscopy-energy spectrometer (SEM-EDS), X-ray photoelectric spectroscopy (XPS), UV–Vis absorption spectrum and photoluminescence spectra technology through the degradation rate of methylene blue (MB) solution. The results showed that the Fe3+ ions were successfully incorporated into the TiO 2 lattice, which had no effect on the crystalline phase of TiO 2 and expanded the spectral response range of TiO 2 from the ultraviolet region to the visible light region. When the calcination temperature was at 450 °C and the number of Fe–TiO 2 sol loading cycles was two times, the photocatalytic activity of Fe–TiO 2 /WBFS presented the strongest, and the degradation ratio of MB reach the maximum value of 98.9 %. A uniform and dense anatase TiO 2 thin film was wrapped on the surface of WBFS. The photocatalytic activity first improved and then weakened with an increase of calcination temperature, Fe3+ doping amounts and the loading cycles of sol. The TiO 2 film changed from thin to thick and uneven to uniform, until cracking and spalling phenomenon finally occurred with an increase of Fe–TiO 2 sol loading cycle from 1 to 3 times. When the Fe–TiO 2 /WBFS was reused for four times, the degradation rate of MB could still show 67.4 %, being far higher than that of TiO 2 /WBFS of 25.4 %. [ABSTRACT FROM AUTHOR]

Using ytterbium nitrate pentahydrate (Yb(NO3)3·5H2O), ammonium metavanadate (NH4VO3) and citric acid monohydrate (C6H8O7·H2O) as main raw materials, the YbVO4 was prepared by sol-gel method. The samples were characterized by thermogravimetry differential scanning calorimeter (TG-DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM), diffuse reflection spectrometer (DRS) and Fourier infrared spectrometer (FT-IR). The photocatalytic activity of YbVO4 was studied by using 10 mg/L methyl orange as simulated wastewater. The results show that pure YbVO4 can be prepared by calcining at 500 °C to 900 °C. The surface of YbVO4 sample prepared at different temperatures is porous and irregular. The forbidden band width of YbVO4 sample calcined at 700 °C is about 3.04 eV. Under ultraviolet light conditions, the degradation rate of methyl orange was over 95% after illumination for 30 min with YbVO4 sample calcined at 700 °C. YbVO4 show excellent photocatalytic activity for degradation of methyl orange. This indicates that YbVO4 is a new photocatalyst with wide application prospect in the field of photocatalysis. [ABSTRACT FROM AUTHOR]

Eu2SmSbO7 and ZnBiEuO4 were synthesized for the first time using the hydrothermal method. Eu2SmSbO7/ZnBiEuO4 heterojunction photocatalyst (EZHP) was synthesized for the first time using the solvothermal method. The crystal cell parameter of Eu2SmSbO7 was 10.5547 Å. The band gap width of Eu2SmSbO7 was measured and found to be 2.881 eV. The band gap width of ZnBiEuO4 was measured and found to be 2.571 eV. EZHP efficiently degraded the pesticide chlorpyrifos under visible light irradiation (VLID). After VLID of 160 min, the conversion rate of the chlorpyrifos concentration reached 100%, while the conversion rate of the total organic carbon (TOC) concentration was 98.02% using EZHP. After VLID of 160 min, the photocatalytic degradation conversion rates of chlorpyrifos using EZHP were 1.13 times, 1.19 times, and 2.84 times those using Eu2SmSbO7, ZnBiEuO4, and nitrogen-doped titanium dioxide (N-doped TiO2), respectively. The photocatalytic activity could be ranked as follows: EZHP > Eu2SmSbO7 > ZnBiEuO4 > N-doped TiO2. The conversion rates of chlorpyrifos were 98.16%, 97.03%, 96.03%, and 95.06% for four cycles of experiments after VLID of 160 min using EZHP. This indicated that EZHP was stable and could be reused. In addition, the experiments with the addition of capture agents demonstrated that the oxidation removal ability of three oxidation free radicals for degrading chlorpyrifos obeyed the following order: hydroxyl radical > superoxide anion > holes. This study examined the intermediates of chlorpyrifos during the photocatalytic degradation of chlorpyrifos, and a degradation path was proposed, at the same time, the degradation mechanism of chlorpyrifos was revealed. This study provides a scientific basis for the development of efficient heterojunction photocatalysts. [ABSTRACT FROM AUTHOR]

A number of carcinogenic dyes and microbial infections have negative effects on living being. These also have a detrimental effect on water quality and responsible for major health problems. ZnO/GO nanocomposites (NCs) (10 wt. % GO) is synthesized via one pot ecofriendly route. It is utilized for photocatalytic degradation of aqueous solution of Malachite green (MG), Crystal violet (CV) and first time mixture of pollutants (CV+MG) dyes in 1 : 2 ratio. These synthesized NCs are analyzed by using many techniques such as P‐XRD, FE‐SEM, HR‐TEM, BET and UV‐Vis spectrophotometer. Kinetics and mechanism of photocatalytic degradation is also explored. The photocatalytic degradation followed the order (CV+MG) (1 : 2) binary system > MG > CV dyes. On the other hand, an antibacterial activity is also investigated against Gram positive (+ve) bacteria such as Staphylococcus aureus (S. aureus), Enterococcus faecalis (E. faecalis) as well as Gram negative (−ve) bacteria such as Escherichia coli (E. coli), and Citrobacter sp. The ZnO/GO NCs followed the antibacterial activity order: E. coli > S. aureus ~ Citrobacter sp. > E. faecalis and the inhibition zones diameters are 20, 15, 15 and 10 mm respectively which is comparable with standard drug Gentamycin. [ABSTRACT FROM AUTHOR]

In this study, we designed a platform based on a laser-driven approach for fast, efficient, and controllable MOF synthesis. The laser irradiation method was performed for the first time to synthesize Zn-based MOFs in record production time (approximately one hour) compared to all known MOF production methods with comparable morphology. In addition to well-known structural properties, we revealed that the obtained ZnMOFs have a novel optical response, including photoluminescence behavior in the visible range with nanosecond relaxation time, which is also supported by first-principles calculations. Additionally, photocatalytic degradation of methylene blue with ZnMOF was achieved, degrading the 10 ppm methylene blue (MB) solution 83% during 1 min of irradiation time. The application of laser technology can inspire the development of a novel and competent platform for a fast MOF fabrication process and extend the possible applications of MOFs to miniaturized optoelectronic and photonic devices. [ABSTRACT FROM AUTHOR]

The preparation of eco-friendly, cost-effective, reusable effective photocatalyst is necessary for remediation of persistent various pollutants. To address this encounter, a unique green method was used to prepare ZnO–SnO2 nanocomposite (NC) using Syzygium cumini leaf (SC) extract. The ZnO–SnO2 was characterized by TEM, FT-IR, XRD, XPS, BET and UV–Vis techniques. The size of ZnO–SnO2 NCs is in the range of 10–15 nm with spherical morphology is confirmed by TEM analysis. By XRD, it was established that the crystal structure of ZnO is hexagonal wurtzite and SnO2 is tetragonal. The BJH plot shows that the prepared ZnO–SnO2 NCs are mesoporous with high surface area (115.42 m2/g). The FT-IR peaks at 523 and 646 cm−1 designate the formation of Zn–O and O–Sn–O bonding, which confirms the formation of ZnO–SnO2 NCs. The increase in ZnO content in the SnO2, the band gap decreases. The photocatalytic activity of ZnO–SnO2 NCs is applied for the degradation of methyl orange (MO) and methylene blue (MB) dyes under UV–Vis light. The ZnO–SnO2 NCs exhibit the degradation efficiencies of 99.5 (MO) and 99.3% (MB) at 1.5 g/dm3 loading of catalyst within 60 and 40 min, respectively. Finally, the ZnO–SnO2 NCs validate the higher photocatalytic activity and reusability for many cycles compared to individual ZnO and SnO2. [ABSTRACT FROM AUTHOR]

Bismuth vanadate (BVO) has been established as an efficient photocatalyst for water remediation and energy applications. Its crystal structure stability, high light quantum and electronic transmission efficiency, and outstanding energy utilization capacity are the main reasons for its enhanced utilization as a robust photocatalytic material. Several studies have reported many synthesis methods and strategies to design highly efficient BVO photocatalysts with different shapes, morphologies, facets, oxygen vacancies. This review systematically encapsulates the effects of morphologies on the photodegradation properties. Here, we have surveyed the synthesis methods of BVO photocatalysts followed by their different synthesized morphologies. The photosensitization mechanism whereby the organic dye plays both the role of photosensitizer as well as sample to be degraded is addressed. Further, we have highlighted the general sequential photocatalytic processes and the recent advances on degradation of three model pollutants (Methylene Blue, Rhodamine B and Methyl Orange). The 3 steps photocatalytic mechanism of BVO photocatalysts have discussed. This review provides also the effects of crystal facets, heterojunction BVO materials and elemental doping on the photocatalytic efficiency. Finally, current status, challenges to improve the photoactivity and the future possible scenarios are summarized. [ABSTRACT FROM AUTHOR]

The key goal of this study is to innovate the pure and 0.05, 0.10 and 0.15 wt.% of Cudoped ZnO NPs through co-precipitation technique. PXRD pattern shows the hexagonal crystal structure with no any phase impurity were observed for all the synthesized samples. From UV-Vis DRS spectra, band gap was obtained as 3.18, 3.24, 3.29 and 3.33 eV respectively for undoped, Cu-doped ZnO NPs (0.05, 0.10 and 0.15 wt.%). From SEM analysis, the agglomeration of rod-like morphology for pure ZnO NPs, spherical-like morphology for Cu-doped ZnO NPs (0.05 wt.%) and flake-like morphology for Cu-doped ZnO NPs (0.10 wt.%) and flower-like morphology for Cu-doped ZnO NPs (0.15 wt.%). The photocatalytic performance of the synthesized NPs was studied by the dye degradation of Methylene Blue (MB) under UV irradiation. The result exposed that, 0.15 wt.% of Cu-doped ZnO NPs is found to have efficient degradation candidate materials. [ABSTRACT FROM AUTHOR]

A groundbreaking photocatalytic nanomaterial, Dy2NdSbO7, was fabricated smoothly using the hydrothermal synthesis technique for the first time. Apart from that, Dy2NdSbO7/Bi2WO6 heterojunction photocatalyst (DBHP) was initially fabricated using the solvothermal fabrication technique. X-ray diffractometer, Fourier-transform infrared spectrometer, Raman spectrometer, UV-visible spectrophotometer, X-ray photoelectron spectrometer, inductively coupled plasma optical emission spectrometer, transmission electron microscope, and X-ray energy dispersive spectroscopy have been applied to evaluate and investigate the thetastructure, morphology, and physicochemical properties of synthesized samples. The results confirmed that the pyrochlore-type crystal structures of Dy2NdSbO7 belonged to the Fd3m space group with the cubic crystal system and the β-pyrochlore-type crystal structures of Bi2WO6 which belonged to the Pca21 space group with orthorhombic crystal system. Under visible light exposure for 155 min (VLP-155min) using DBHP in the capacity of the photocatalytic nanomaterial, the removal efficiency of chlorpyrifos (CPS) saturation reached 100%. Comparison of CPS removal efficiency after VLP-155min revealed that DBHP exhibited higher removal efficiency than Dy2NdSbO7, Bi2WO6, or N-doped TiO2 photocatalyst, with removal efficiency 1.15 times, 1.23 times, or 2.55 times higher, respectively. Furthermore, the oxidizing capability of free radicals was investigated using trapping agents. Results demonstrated that superoxide anions exhibited the strongest oxidative capability, followed by hydroxyl radicals and holes. The results presented in this study lay a robust groundwork for future investigations and advancements in the field of highly efficient heterostructure material. These findings have significant implications for the development of environmental remediation strategies and provide valuable insights into sustainable solutions for addressing CPS contamination. [ABSTRACT FROM AUTHOR]

This work reports the synthesis of semiconductor selenium nanoparticles/micro-rods (Se-NP/MRs) using the bio-fabrication approach and studies its photocatalytic activity under natural sunlight irradiation. Cabbage leaf extract was used as a reducing agent to fabricate Se-NP/MRs. X-ray diffraction patterns shown the crystalline structure with a crystallite size of 28.17 nm, conferring to planes of hexagonal structure. A characteristic sharp resonance peak in Raman spectra at 235 cm−1 endorsed to the Se – Se bond of crystalline Se-NP/MRs. The prominent peak in the FTIR spectra at 621 cm−1 supported the formation of Se-NP/MRs. Scanning electron micrograph revealed a nearly spherical shape with irregular layers in the 35‒95 nm size range. In contrast, the dimension of the micro-rods was observed to be ~ 10 µm in length and 2.5 µm in diameter. The bandgap energy of Se-NP/MRs was analysed to be 2.14 eV using the Tauc plot. The exciting photocatalytic performance of the bio-fabricated Se-NP/MRs revealed that the methylene blue degradation was ~ 86% in 40 min and ~ 97% in 140 min. Kinetic analysis shows that the pseudo-second-order correlation coefficient is well fitted compared to the pseudo-first-order. Therefore, this work opens the door to further exploration of nano-materials/composites with mixed nanoparticles/micro-rods morphology for sustainable applications in the removal of various textile and industrial contaminants. [ABSTRACT FROM AUTHOR]

An unprecedented photocatalyst, Sm2EuSbO7, was successfully fabricated in this paper, through a high-temperature solid-state calcination method, which represented its first ever synthesis. Additionally, using the solvothermal method, the Sm2EuSbO7/ZnBiSbO5 heterojunction photocatalyst (SZHP) was fabricated, marking its debut in this study. XRD analysis confirmed that both Sm2EuSbO7 and ZnBiSbO5 exhibited pyrochlore-type crystal structures with a cubic lattice, belonging to the Fd3m space group. The crystal cell parameter was determined to be 10.5682 Å or 10.2943 Å for Sm2EuSbO7 or ZnBiSbO5, respectively. The band gap width measured for Sm2EuSbO7 or ZnBiSbO5 was 2.73 eV or 2.61 eV, respectively. Under visible light irradiation for 150 min (VLTI-150 min), SZHP exhibited remarkable photocatalytic activity, achieving 100% removal of parathion methyl (PM) concentration and 99.45% removal of total organic carbon (TOC) concentration. The kinetic constant (k) for PM degradation and visible light illumination treatment was determined to be 0.0206 min−1, with a similar constant k of 0.0202 min−1 observed for TOC degradation. Remarkably, SZHP exhibited superior PM removal rates compared with Sm2EuSbO7, ZnBiSbO5, or N-doped TiO2 photocatalyst, accompanied by removal rates 1.09 times, 1.20 times, or 2.38 times higher, respectively. Furthermore, the study investigated the oxidizing capability of free radicals through the use of trapping agents. The results showed that hydroxyl radicals had the strongest oxidative capability, followed by superoxide anions and holes. These findings provide a solid scientific foundation for future research and development of efficient heterojunction compound catalysts. [ABSTRACT FROM AUTHOR]

N- and S-doped CQDs were prepared using L-cysteine as a precursor. Different NS-CQDs/g-C3N4 composite photocatalysts were formed by modifying graphite-phase carbon nitride with different contents of NS-CQDs using a hydrothermal method. The morphology, constituent elements and functional groups of the composite photocatalysts were analyzed by SEM, EDS, TEM, Mapping, XRD and FT-IR as a proof of its successful preparation. Meanwhile, it was characterized by PL, UV-Vis DRS and electrochemical impedance, which proved that the CQDs could be used as an electronic memory in the composite system to accelerate the electron transfer induced by the photo-excitation of g-C3N4 and effectively inhibit the recombination of e−-h+ improvement of the photocatalytic activity of g-C3N4. The stability of the composite photocatalysts under different conditions and the photodegradation activity of Rh B under visible light were investigated. It was found that the photocatalytic degradation efficiency of rhodamine B by NS-CQDS-modified g-C3N4 was significantly higher than that of pure g-C3N4, which could reach 90.82%, and its degradation rate was 3.5 times higher than that of pure g-C3N4. It was demonstrated by free radical trapping experiments that ·OH and ·O2− were the main active species in the photocatalytic degradation process, in which ·O2− played a guiding role. [ABSTRACT FROM AUTHOR]

WO 3 nanoparticles were grown hydrothermally on porous titania (TiO 2) PEO-coated on Ti in an alkaline electrolyte using pulsed direct current mode. To achieve the best photodegradation of methylene blue (MB) mediated by the PEO/HT hybrid coatings under visible illumination, hydrothermal parameters including precursor concentration, temperature, and time were optimized. In this sense, increasing the Na 2 WO 4 concentration resulted in a decrease in porosity percentage and an increase in average particle size. At an optimal precursor concentration of 0.005 M, the TiO 2 /WO 3 hybrid coating exhibited 67% degradation compared to ∼47% degradation for a bare TiO 2 coating. Based on the LaMer diagram, the growth mechanism of WO 3 crystals under the hydrothermal process was described. The calculated band gap of the PEO/HT coatings reduced from 3.0 eV to 2.68 eV with an increase in W-based precursor content through the hydrothermal process. Consequently, the improvement in photocatalytic performance was attributed to the participation of more WO 3 nanoparticles and the expansion of the light absorption range of TiO 2 up to the visible light range. Increasing the hydrothermal temperature led to an increase in crystallinity and particle size due to growth, but a decrease in porosity. The optimal photocatalytic performance was achieved for the hybrid coatings at a concentration of 0.005 M, with a hydrothermal temperature of 120 °C and treatment time of 18 h, resulting in ∼88% degradation of methylene blue after 360 min of irradiation. The study of photoactivity on a pollutant model indicates that the resulting activity is primarily influenced by the morphology of hybrid coatings, followed by their specific surface area. [ABSTRACT FROM AUTHOR]

In this work, the influence of Yb-incorporated ion on relevant physical, morphological, optical, and also photocatalytic properties of Er-doped bismuth vanadate powders synthesized by the facile sonochemical method was investigated. The Er3+ doping content was fixed at 1% and Yb3+ ion content was designated at 2, 4, 6, 8, and 10%. To study the relevant properties of the prepared samples, XRD, FE-SEM, FTIR, DRS, and UV-visible spectrometry were employed to characterize their morphology, crystal structure, functional group, energy gap, and photocatalytic degradation, respectively. The experimental results show that Yb ion incorporation has a significant effect on the decrease in its particle size and the change in morphology and the monoclinic-to-tetragonal phase change of the sample. The DRS result exhibits two extinct absorption edges belonging to the monoclinic and tetragonal phases, accompanying the characteristic absorption due to energy transitions of both Er3+ and Yb3+. The incorporation of Yb3+ ion with certain content exhibits noticeable enhancement in the photocatalytic performance of the Er-doped BiVO4 catalyst under the visible light illumination, which may be a result of the significant increase in the active surface area, increasing charge separation of mixed phases and possible up-conversion process. [ABSTRACT FROM AUTHOR]

This work emphasis on the synthesis of Ni0.2Mn0.02Zn0.02O nanoparticles by facile sol‐gel method. The photocatalytic activity was studied for the degradation of methylene blue (MB) dye under the UV light as a function of dye initial concentration, catalyst dose and pH of the medium. Scanning electron microscopy (SEM) and energy dispersive X‐ray (EDX) were utilized for the study of morphological and elemental composition, while XRD analysis was employed for structural study of the prepared material, which formation the phase purity and size was in 20–24 nm range. The bandgap of Zn/Mn co‐doped NiO NPs (3.24 eV) was reduced as compared to pure NiO NPs (3.43 eV). The degradation efficiency of pure NiO NPs and Zn/Mn co‐doped NiO NPs was found to be 70 % (60 min) and 94 % at optimum conditions. The dielectric properties were also studied, which were also improved in response of doping. The findings revealed that the optical and catalytic properties of Zn/Mn co‐doped NiO NPs were improved versus pure NiO NPs, which could be employed for the remediation of dyes in effluents. [ABSTRACT FROM AUTHOR]

This work presents an important analysis and comparative study between two organic waste rhodamine B (RhB) and methyl orange (MO) dyes as pollutant models degeneration under sunlight. Hematite (α -Fe2O3) nanorods were synthesized and deposited on glass substrates using an efficient and simple one-step hydrothermal method. The nanorods were characterized by XRD, FESEM, EDX, and UV–Vis equipment. The photodegeneration parameters of α -Fe2O3 films were calculated by modeling the photodegradation of MO and RhB dyes as pollutants under sunlight irradiation for 150 min. Results revealed that the degradation efficiency of α -Fe2O3 films of MO and RhB dyes was 72.7% and 91.9%, respectively. The optimized photocatalyst degraded RhB more efficiently than the MO solution. [ABSTRACT FROM AUTHOR]

The development of eco-friendly photocatalysts is gaining attention as an effective approach for degrading organic pollutants. In the present study, the composite materials are composed of various components with varying structures that combine to enhance their characteristics and widen their applications. This work uses the hydrothermal method for the fabrication of a novel and steady SiO2/g-C3N4 photocatalyst. The amount of SiO2 was fixed, and graphitic carbon nitride (g-C3N4) was varied in the ratio (1:x, where x = 1, 2, 3) and abbreviated as SCN1, SCN2, and SCN3. The optical properties, surface morphology, and structural analysis of the prepared nanocomposites were studied using various techniques such as FTIR, TGA, X-ray diffraction, and ultraviolet–visible spectroscopy. The results show that SCN2 nanocomposites significantly improved the photocatalytic activity, with a degradation efficiency of 70% for auramine O and 84.6% for xylenol orange dye under visible light irradiation, which is a result of their large surface area and efficient electron–hole separation rate. [ABSTRACT FROM AUTHOR]

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In this work, the UV-photodegradation efficiency of a novel TiO2–ZnO/ Banana activated carbon photocatalyst composite monitored by colour and chemical oxygen demand reduction of rhodamine 6 G dyes in a 6 W-UV photoreactor system was investigated. A TiO2–ZnO Banana activated carbon photocatalyst composite was synthesized by immobilizing ZnO on TiO2 and subsequently supporting the TiO2–ZnO hybrid on banana peel activated carbon. X-ray diffraction patterns and Fourier transform infrared revealed the successful TiO2–ZnO hybridization and the introduction of Banana activated carbon. Photoluminescence spectroscopy and solid-state electronic absorption spectra confirmed restrained electron–hole recombination and reduced bandgap energy attributed to Banana activated carbon as an electron acceptor and heterojunction formation, respectively, which enhanced photocatalytic activity. Photocatalytic results showed that TiO2–ZnO Banana activated carbon (51:9:40) showed a higher colour removal of 96% compared to 46%, 31%, and 56%, respectively, for TiO2, ZnO and TiO2–ZnO (85:15) after 160 min of irradiation time. The study also revealed that UV-photodegradation is more effective in colour removal of the rhodamine 6 G dye with about 96% as compared to 79% Chemical Oxygen Demand reduction. The colour removal of rhodamine 6 G dye was still as high as 90% after four runs, confirming the good stability and reusability of the TiO2–ZnO Banana activated carbon composite. The optimum pH and temperature for photodegradation were found to be 8 and 40 ℃, respectively. Through modification, TiO2–ZnO/Banana activated carbon composite was found to be an economical and environmental feasible photocatalyst. [ABSTRACT FROM AUTHOR]

The present study is mainly concerned with the development of cost-efficient composite material utilized to produce one-dimensional manganese oxide (α-MnO2) nanoparticles coated on two-dimensional graphitic carbon nitrides (HT-GCN) as nanocomposite (α-MnO2/HT-GCN) for highly efficient CIP degradation. The α-MnO2 nanoparticles (NPs) were prepared by a simple hydrothermal technique before being decorated on HT-GCN (H denotes protonation and T represents thermal-decomposition–graphitic carbon nitride). Tauc plots were used to calculate the band gap values of the photocatalysts α-MnO2 (1.74 eV), GCN (2.84 eV), HT-GCN (2.63 eV), and α-MnO2/HT-GCN (2.31 eV). The mechanism was investigated by various scavengers, particularly isopropanol (•OH) makes a significant role in the photodegradation process. The degradation percentage for ciprofloxacin was 89.2% and the rate of reaction R2 = 0.9913. This study demonstrates a unique method for developing a heterojunction-based nanocomposite of α-MnO2/HT-GCN, which exhibit better light absorption performance. [ABSTRACT FROM AUTHOR]

The flower-structured CNNS@Bi 2 WO 6 heterostructure photocatalsts with enhanced photocatalytic performance were successfully fabricated by facile in-situ hydrothermal method. Compared with the g-C 3 N 4 nanosheets (CNNS) and pure Bi 2 WO 6 , the flower-structured CNNS@Bi 2 WO 6 heterostructure photocatalysts exhibited better photocatalytic performance and photocatalytic stability for degradation of rhodamine B (RhB) and tetracycline (TC) under visible. The effects of different CNNS contents on the photocatalytic efficiency of the heterostructure photocatalysts have been investigated. The results show that the CNNS@Bi 2 WO 6 heterostructure photocatalst with CNNS mass ratio of 7% presents the best photocatalytic performance. The photocatalytic activity enhancement should be attributed to the effective separation of photogenerated electron-hole pairs and the efficient visible-light utilization efficiency. Compared with CNNS, the absorption of CNNS@Bi 2 WO 6 photocatalysts in the visible region has been greatly strengthened, with red-shift absorption edge by the UV–vis diffuse reflectance spectra (DRS). The connection between CNNS and Bi 2 WO 6 was studied by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The scavenging experiments with different trapping agents demonstrates that the photogenerated h+ in the system can play the main role during the RhB degradation process. Subsequently, the possible mechanism of photocatalytic degradation over flower-structured CNNS@Bi 2 WO 6 heterostructure photocatalysts has been proposed. [Display omitted] • Flower-structured CNNS@Bi 2 WO 6 constructed by in situ hydrothermal method. • The flower-structured photocatalyst with excellent photocatalytic performance. • The photocatalyst exhibiting good photocatalytic stability. [ABSTRACT FROM AUTHOR]

This study reports the synthesis of Mg0.33Ni0.33Co0.33GdxFe2‐xO4 nanoparticles (NPs) with 0.00≤x≤0.08 by the co‐precipitation method. The structural and optical properties of NPs are investigated. As Gd content increases, the lattice parameter and the bandgap energy increase whereas the particle size decreases. The photocatalytic performance of NPs is evaluated in the degradation of methyl violet (MV) dye under sunlight irradiation. The best activity is exhibited by Mg0.33Ni0.33Co0.33GdxFe2‐xO4 where x=0.04. The rate of the photodegradation reaction is boosted by increasing the pH and temperature. 95.4 % of MV is degraded after 240 min upon the addition of 5 wt. % carbon dot. The NPs are tested against Gram‐positive (Staphylococcus aureus and Enterococcus faecium) and Gram‐negative bacteria (Escherichia coli and Leclercia adecarboxylata) isolated from wastewater. The antibacterial activity was tested by the minimum inhibitory concentration and minimum bactericidal concentration broth microdilution assay, agar well diffusion assay and time‐kill test. The results show that the NPs exhibit inhibitory activity against Gram‐positive bacteria. Furthermore, NPs show bacteriostatic activity after 3 hours of incubation. The antibiofilm activity of the NPs is tested by the inhibition of biofilm formation and the destruction of pre‐formed biofilm assays. The results show an inhibitory activity of the NPs against Gram‐positive biofilms. [ABSTRACT FROM AUTHOR]

In this work, two-dimensional (2D) Zn-HMT (Zn(NO3)2(HMT)2(H2O)2]n) nanosheets were synthesized using a facile one-step chemical precipitation in the presence of Zn(NO3)2, hexamine (HMT), and anhydrous ethanol at room temperature. Subsequently, hexagonal Tx-ZnO (Tx-ZnO refers to the zinc oxide (ZnO) nanoparticles) were synthesized by a high-temperature solid-phase method at different temperatures (x = 500, 550, 600, 650, 700, 750, and 800 °C) nanoparticles with different morphologies were synthesized by a high-temperature calcination approach using 2D Zn-HMT nanosheets as precursor. The crystal structure, morphology, specific surface areas, surface and interface properties, optical properties, and charge migration behaviors of the as-synthesized Tx-ZnO nanoparticles were characterized by powder X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), automatic specific surface and aperture analyzer, X-ray photoelectron spectroscopy (XPS), UV-visible spectrophotometer, photoluminescence (PL) spectra, and electrochemical impedance spectroscopy (EIS). The photocatalytic performances and stabilities of the as-synthesized typical Tx-ZnO nanoparticles with various morphologies were evaluated and compared with the commercial ZnO (CM-ZnO) nanoparticle. The T700-ZnO nanoparticle with spherical and irregular morphology exhibited the highest photocatalytic activity (99.12%) for the degradation of Rhodamine B (RhB), compared to T500-ZnO (92.32%), T600-ZnO (90.65%), T800-ZnO (44.04%), and the CM-ZnO (88.38%) nanoparticle, which can be attributed to the cooperative effects of higher crystallinity, bigger crystal size, the strongest separation efficiency, the lowest recombination rate, the fastest charge carrier transfer path, and the highest charge-transfer efficiency. The superior photocatalytic activity illustrated by the T700-ZnO nanoparticle makes it have potential application prospects for the treatment of organic wastewater. [ABSTRACT FROM AUTHOR]

A polyacrylamide gel method combined with low temperature calcination technology has been developed to synthesize the BaTiO3/CeO2 heterojunction photocatalysts, which were formed by hybriding the large BaTiO3 particles and fine CeO2 nanoparticles with varied mass percent of CeO2. Various characterization methods have been used to determine the phase structure, functional group information, elemental composition, microstructure, optical and photocatalytic activity of BaTiO3/CeO2 heterojunction photocatalysts. The introduction of CeO2 into the host lattice of BaTiO3 does not change the optical band gap value (Eg = 3.20 eV) of the host lattice. As expected, the BaTiO3/CeO2 heterojunction photocatalysts exhibit highly enhanced and CeO2 composition-dependent photocatalytic activity for the degradation of oxytetracycline hydrochloride under simulated sunlight irradiation. The BaTiO3/5 wt% CeO2, BaTiO3/10 wt% CeO2, and BaTiO3/15 wt% CeO2 showed lower photocatalytic activity, while BaTiO3/20 wt% CeO2 showed highest photocatalytic activity (96.89 %) over the single component BaTiO3 and CeO2 photocatalysts with the initial oxytetracycline hydrochloride concentration, photocatalyst content and irradiation time were 100 mg/L, 1.5 g/L and 120 min, respectively. The enhanced photocatalytic activity of BaTiO3/20 wt% CeO2 heterojunction photocatalysts is ascribed to the cooperation between Ce3+ and Ce4+, improved charge transfer and separation of electron-hole pairs generated on irradiation with simulated sunlight and proper amount of surface defects or oxygen vacancies on the BaTiO3/CeO2 heterojunction photocatalysts. [ABSTRACT FROM AUTHOR]

The effects of Argon (Ar) on the Synthesis and Photocatalytic activities of monolayer Graphene under the flow of Methane (CH4) and Hydrogen (H2) gas has been studied. The Chemical Vapor Deposition (CVD) method was used to create a large area of monolayer graphene with features that meet the needs of a wide variety of applications. With this, the possibility of varying the dimensions of graphene by differing the argon gas while keeping other parameters constant was demonstrated. This helps with the ability to control the size and number of layers of graphene for different applications. Further, the photocatalytic activities of produced graphene were examined during CVD at various argon gas flow rates to observe their effects on the performances of graphene. The result shows that the synthesized graphene at Ar = 80 sccm is a monolayer with perfectly shaped edges. After exfoliation, the graphene obtained was properly formed with a large surface area, which helped achieve the results of higher photocatalytic activity. [ABSTRACT FROM AUTHOR]

The biosynthesis procedure for nanomaterial preparation is a promising alternative due to its simplicity and environmental friendliness. In this work, TiO2 NPs were biosynthesized using the aqueous leaf extract of Azadirachta indica. The influence of the extract volumes, solvents, and acetic acid on the properties of TiO2 NPs was studied. Phytochemical screening and ATR-FTIR spectrum confirmed the presence of phenolic compounds in the leaf extract. XRD patterns showed that the samples were mainly in the anatase phase. However, for the water-based samples and when 1 and 2 mL of extract volumes were used, anatase/brookite mixture was observed. FESEM images displayed almost spherical and agglomerated NPs. UV-Vis-NIR studies showed that the samples’ bandgaps values are within the range of anatase TiO2. The photocatalytic activity of the TiO2 NPs was evaluated in the photodegradation of methyl orange (MO) under UV light irradiation. The water-based sample synthesized using 2 mL of the extract achieved 98.62% of MO degradation within 270 min and demonstrated the highest pseudo-first-order photodegradation kinetic constant of 0.0147 min-1. These results indicate that the use of the plant-based biosynthesis method with water as the solvent successfully produced TiO2 NPs with good physicochemical properties and photocatalytic activity in the photodegradation of organic dye. Copyright © 2022 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).