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Industrial dye effluent causes significant risks to the environment. The present study was focused on photocatalytic degradation of the dye Direct Red 28 using a ternary composite of graphitic carbon nitride, TiO2, and polyorthoanisidine (g-C3N4/TiO2/ POA), prepared by in-situ oxidative polymerization o-anisidine. The synthesized composite g-C3N4/TiO2/POA properties were characterized using different analytical techniques. X-ray diffraction (XRD) results revealed the prominent pattern of TiO2 and g-C3N4 in the composite peak at 2θ° while Fourier transform infrared (FTIR) results provided the confirmation peaks for g-C3N4/TiO2/POA and POA at 1,110 cm-1 and 1,084 cm-1 for C-O-C ether. Scanning electron microscopy (SEM) demonstrated an increase in the average size of the composite up to 428 nm. The energy-dispersive X-ray spectroscopy (EDX) spectrum provided the weight percentages of the C, O, and Ti in the composite were 8.5%, 45.69%, and 45.81%, respectively. The photocatalytic degradation of Direct Red 28 dye under UV irradiation using a composite showed that 86% Direct Red 28 dye was degraded by a 30 mg/L dose of g-C3N4/TiO2/POA in 240 min at pH 2. After four consecutive cycles, the utilized composite showed 79% degradation of Direct Red 28, demonstrating the stability and effectiveness of the g-C3N4/TiO2/POA photocatalyst. The high reusability and efficiency of the g-C3N4/TiO2/POA composite are due to increased light absorption range and reduced e-/h+ recombination rate in the presence of g-C3N4 and POA. [ABSTRACT FROM AUTHOR]

The photodegradation and deadhesion of mussel-inspired polydopamine was reported from nanoscale disassembly to effective mineralization. Various PDA coated templates and PDA hollow structures can be photodegraded by this strategy. The patterned and gradient surfaces were prepared by the "top-down" method under the control of light scope and intensity, respectively. [Display omitted] Mussel-inspired polydopamine (PDA) coating has been utilized extensively as versatile deposition strategies that can functionalize surfaces of virtually all substrates. However, the strong adhesion, stability and intermolecular interaction of PDA make it inefficient in certain applications. Herein, a green and efficient photocatalytic method was reported to remove adhesion and degrade PDA by using TiO 2 -H 2 O 2 as photocatalyst. The photodegradation process of the PDA spheres was first undergone nanoscale disassembly to form soluble PDA oligomers or well-dispersed nanoparticles. Most of the disassembled PDA can be photodegraded and finally mineralized to CO 2 and H 2 O. Various PDA coated templates and PDA hollow structures can be photodegraded by this strategy. Such process provides a practical strategy for constructing the patterned and gradient surfaces by the "top-down" method under the control of light scope and intensity. This sequential degradation strategy is beneficial to achieve the decomposition of highly crosslinked polymers. [ABSTRACT FROM AUTHOR]

This study reports the biosynthesis of FeMn2O4 nanocomposite (NC) using an aqueous leaf extract of Artemisia. The FeMn2O4 NC was characterized by zeta potential, SEM, XRD, and FTIR. X-ray diffraction analysis confirmed that the biosynthesized FeMn2O4 NC has a cubic crystal nature with a crystallite size of 28.45 nm. Scanning electron microscopy images showed that the FeMn2O4 NC has a spherical shape. The optical bandgap energy of the FeMn2O4 NC was estimated to be approximately 2.94 eV for direct bandgap and 1.27 eV for indirect bandgap. The photocatalytic activity of the FeMn2O4 NC was evaluated for the degradation of amoxicillin and cephalexin antibiotics under sunlight irradiation, resulting in a degradation efficiency of 99% for both drugs. The FeMn2O4 NC also exhibited excellent degradation efficiency against Congo Red (CR) and Methylene Blue (MB) dyes with about 83.23% and 100%, respectively, after just 40 min. The reaction kinetic calculations showed that the absorption of both dyes and antibiotics by the adsorbent followed a pseudo-first-order model. The equilibrium isotherms revealed that the amoxicillin and cephalexin absorption process through the synthesized magnetic nanocomposite was consistent with the Langmuir model. These findings suggest that the FeMn2O4 NC can serve as a promising absorbent for the removal of amoxicillin and cephalexin antibiotics as well as MB and RC dyes from aqueous solutions. [ABSTRACT FROM AUTHOR]

Graphite-phase carbon nitride (g-C 3 N 4) is widely recognized as a remarkable material for both the photocatalytic degradation of organic pollutants and photocatalytic water splitting for hydrogen production. In this study, we reported a method to obtain a broken hollow carbon nitride with nitrogen defects and hydroxyl groups, prepared from melamine and cyanuric acid through self-assembly. It demonstrated outstanding photocatalytic performance, achieving a 99.35% removal of Rhodamine B, 88.08% degradation of tetracycline hydrochloride, and a hydrogen production rate of 1671.12 μmol g−1 h−1, all of which are superior to the performance of bulk g-C 3 N 4. The superior redox performance was attributed to the significant increase in specific surface area and the synergistic effects of nitrogen defects and hydroxyl groups. These modifications effectively altered the built-in electric field, electronic structure, and redox potential of g-C 3 N 4. Experimental and theoretical analyses revealed that photogenerated electrons were enriched in nitrogen vacancies, while holes were captured by hydroxyl groups, resulting in the rapid transfer and separation of charge carriers. On this basis, possible synthesis pathways and photocatalytic mechanisms of the catalyst were proposed. This work provides a promising method for preparing modified carbon nitride with excellent photocatalytic performance. [Display omitted] • V N -CN-OH-45 shows a unique broken hollow tubular structure. • Nitrogen defects and hydroxyl groups synergistically enhance redox capacity. • DFT calculations indicate that defects facilitate charge separation and transfer. • Exceptional photocatalytic degradation of RhB and TCH. • Outstanding photocatalytic hydrogen production performance. [ABSTRACT FROM AUTHOR]

For heterojunction system, the lack of stable interfacial driving force and definite charge transfer channel makes the charge separation and transfer efficiency unsatisfactory. The photoreaction mechanism occurring at the interface also receives less attention. Herein, a 2D/2D Z‐scheme junction BiOBr@NiFe‐LDH with large‐area contact featured by short interface hydrogen bonds and strong interfacial electric field (IEF) is synthesized, and in situ photoinduced metallic species assisting charge transfer mechanism is demonstrated. The hydrogen bonds between O atoms from BiOBr and H atoms from NiFe‐LDH induce a significant interfacial charge redistribution, establishing a robust IEF. Notably, during photocatalytic reaction, Bi0 and Ni0 are in situ performed in heterojunction, which separately act as electron transport mediator and electron trap to further accelerate charge transfer efficiency up to 71.2 %. Theoretical calculations further demonstrate that the existence of Bi0 strengthens the IEF. Therefore, high‐speed spatial charge separation is realized in Bi0/BiOBr@Ni0/NiFe‐LDH, leading to a prominent photocatalytic activity with a tetracycline removal ratio of 88.3 % within 7 min under visible‐light irradiation and the presence of persulfate, far exceeding majority of photocatalysts reported previously. This study provides valid insights for designing hydrogen bonding heterojunction systems, and advances mechanistic understanding on in situ photoreaction at interfaces. [ABSTRACT FROM AUTHOR]

Construction of S-scheme heterojunctions can effectively limit the recombination of photogenerated e− and h+, thus improving photocatalytic activity. Therefore, S-scheme ZnO/BiOCl (molar ratio = 1:2) n–n heterojunctions were synthesized via a hydrothermal–hydrolysis combined method in this study. The physical and chemical properties of the ZnO/BiOCl heterojunctions were characterized by XRD, XPS, SEM, TEM, DRS, N2 adsorption–desorption and ESR. Additionally, the photoelectric performances of ZnO/BiOCl heterojunctions were investigated with TPR, M–S plot and EIS. The results show that photocatalytic degradation of NOR by ZnO/BiOCl reached to 94.4% under simulated sunlight, which was 3.7 and 1.6 times greater than that of ZnO and BiOCl, respectively. The enhanced photodegradation ability was attributed to the enhancement of the internal electric field between ZnO and BiOCl, facilitating the active separation of photogenerated electrons and holes. The radical capture experiments and ESR results illustrate that the contribution of reactive species was in descending order of ·OH > h+ > ·O2− and a possible mechanism for the photodegradation of NOR over S-scheme ZnO/BiOCl heterojunctions was proposed. [ABSTRACT FROM AUTHOR]

The large-scale utilization of antibiotics has opened a separate chapter of pollution with the generation of reactive drug-resistant bacteria. To deal with this, in this work, different mass ratios of CoFe2O4/WO3 nanocomposites were prepared following an in situ growth method using the precursors of WO3 and CoFe2O4. The structure, morphology, and optical properties of the nanocomposite photocatalysts were scrutinized by X-ray diffraction (XRD), UV-visible diffuse reflectance spectra (UV-Vis DRS), photoluminescence spectrum (PL), etc. The experimental data signified that the loading of CoFe2O4 obviously changed the optical properties of WO3. The photocatalytic performance of CoFe2O4/WO3 composites was investigated by considering tetracycline as a potential pollutant. The outcome of the analyzed data exposed that the CoFe2O4/WO3 composite with a mass ratio of 5% had the best degradation performance for tetracycline eradication under the solar light, and a degradation efficiency of 77% was achieved in 20 min. The monitored degradation efficiency of the optimized photocatalyst was 45% higher compared with the degradation efficiency of 32% for pure WO3. Capturing experiments and tests revealed that hydroxyl radical (·OH) and hole (h+) were the primary eradicators of the target pollutant. This study demonstrates that a proper mass of CoFe2O4 can significantly push WO3 for enhanced eradication of waterborne pollutants. [ABSTRACT FROM AUTHOR]

Titanium dioxide thin films on the inner wall of quartz tubes were prepared in situ by the sol–gel method. Meanwhile, copper and cerium were loaded onto the surface of the titanium dioxide thin films to enhance photocatalytic activity and broaden the range of light absorption. X-ray diffractometer, X-ray photoelectron spectroscopy, scanning electron microscopy, energy dispersive X-ray spectrum, N2 gas adsorption, UV diffuse reflectance spectroscopy, electron paramagnetic resonance, photoluminescene spectroscopy, and so on were used to characterize the structure, morphology, chemical composition, and optical properties of the prepared photocatalyst. Methylene blue (MB) was used as a simulated organic pollutant to study the photocatalytic performance of the photocatalyst, which was a translucent, structurally stable, and reusable high-efficiency photocatalytic catalyst. Under UV lamp irradiation, the MB photodegradation efficiency was 94.5%, which reached 91.2% after multiple cycles. [ABSTRACT FROM AUTHOR]

In this study, a novel Z-scheme heterojunction based on g-C3N4/TiO2/NiCo2O4 nanocomposite was synthesized using a combination of hydrothermal and ultrasonic methods and investigated the photocatalytic degradation of Rhodamine B (RhB) dye. The synthesized nanocomposite was characterized XRD, FT-IR, FE-SEM, TEM, EDS, PL, UV–Vis DRS techniques. Subsequently, various parameters such as the effect of NiCo2O4 amount in the composite structure, pH, initial pollutant concentration, photocatalyst dosage, and different scavengers were investigated to determine the exact mechanism of the photocatalytic process. In different concentrations of NiCo2O4, the base value (X: 1) was determined as the optimal value in photocatalytic degradation. g-C3N4/TiO2/NiCo2O4 composite had the highest percentage of 99.5% Rh.B dye degradation in 60 min. In addition, by examining the pH, it was found that its optimal value is 7, and the rate of dye degradation in this condition is more than other materials, and the rate constant value is 0.069 min–1. In addition, the g-C3N4/TiO2/NiCo2O4 catalyst showed good performance for each reuse and retained about 82% of its initial photocatalytic activity after 5 cycles. The results indicate that photoinducd (RhB) holes play a crucial role in the photocatalytic degradation of RhB in the presence of the g-C3N4/TiO2/NiCo2O4 nanocomposite via pair Z-scheme system. In the Z-scheme system, the rapid recombination between the hole-electron pair is not observed due to the electron trapping effect of the needle-shaped NiCo2O4 structure, resulting in high photocatalytic efficiency and dye degradation. Therefore, Z-scheme systems are efficient and effective for the removal of water pollutants. [ABSTRACT FROM AUTHOR]

This study investigates the synthesis, characterization, and application of ZnO/SnO2 nanocomposite (ZnO/SnO2 NC), focusing on their photocatalytic and antioxidant properties. The sol-gel technique was utilized for the synthesis of the ZnO/SnO2 NC. Subsequent characterization was performed using X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and UV-visible (UV-Vis) spectrophotometry. The XRD analysis indicated crystallite dimensions of 15 nm for ZnO/SnO2 and 21 nm for pure ZnO NPs. The photocatalytic efficiency was assessed by the degradation of Toluidine Blue (TB) and m-Toluidine Blue (m-TB) dyes. The ZnO/SnO2 NC demonstrated degradation rates of 99% for both TB and m-TB within 120 and 140 min of sunlight exposure, respectively. Furthermore, the scavenging activity of superoxide radicals was evaluated, with the ZnO/SnO2 NC exhibiting an Half-maximal inhibitory concentration (IC50) value of 48.12 µg∙mL− 1, compared to 60.03 µg∙mL− 1 for pure ZnO. This research highlights the potential of ZnO/SnO2 NC in environmental remediation and biomedical applications. [ABSTRACT FROM AUTHOR]

Tetracycline hydrochloride (TCN), widely recognized for its broad-spectrum efficacy and cost-effectiveness as an antibiotic, has raised significant environmental and health concerns due to its contamination in water bodies. This study introduces an innovative approach to address this issue by employing a titanium dioxide/graphitic carbon nitride (TiO2/g-C3N5) nanocomposite through photocatalysis. The synthesis of this composite involved a hydrothermal method, and a comprehensive characterization was conducted using XRD, FT-IR, and SEM techniques. The formed heterojunction between TiO2 and g-C3N5 exhibited remarkable photocatalytic degradation capabilities, achieving a removal rate of over 85 % within a short period of 135 min. This signifies the composite's efficiency in breaking down TCN in aqueous environments. Beyond its high effectiveness, the TiO2/g-C3N5 nanocomposite presents itself as an environmentally friendly and sustainable solution for addressing the critical issues associated with antibiotic contamination in water. This study underscores the potential of photocatalysis using TiO2/g-C3N5 as a promising technology for mitigating the adverse effects of TCN on both ecosystems and human health. [ABSTRACT FROM AUTHOR]

In this study, MXene nanosheets were utilized as a co-catalyst to modify the graphitic carbon nitride photocatalyst and synthesize the g-C3N4/MXene composite. Eosin Y dye was employed as a model organic pollutant to evaluate the photocatalytic degradation performance. Eosin Y, an anionic dye, poses significant environmental and health risks due to its resistance to biodegradation, as well as its toxicity and carcinogenicity. To synthesize this composite, graphitic carbon nitride was initially produced using a simple thermal polymerization method. Subsequently, it was protonated and assembled with MXene nanosheets through a self-assembly process. The MXene nanosheets were synthesized using a Mild method. Characterization and confirmation of the successful synthesis of the g-C3N4/MXene composite were conducted through X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and energy-dispersive X-ray spectroscopy (EDS) analyses. The results of the Eosin Y degradation experiments indicated that the composite with a 7% weight ratio of MXene nanosheets exhibited the highest photocatalytic performance among the various weight ratios tested. The incorporation of MXene nanosheets more than doubled the photocatalytic degradation efficiency of graphitic carbon nitride. The MCN7 sample was able to remove 98% of 25 mg/L Eosin Y dye from an aqueous solution within 120 minutes, using a photocatalyst dosage of 0.4 g/L. The findings of this study demonstrate that the integration of MXene nanosheets with graphitic carbon nitride significantly enhances the photocatalytic performance of graphitic carbon nitride in the degradation of organic pollutants. [ABSTRACT FROM AUTHOR]

This study aimed to create composite nonwoven fabric from polylactic acid (PLA) and nano-silver coated titanium dioxide (Ag/TiO2) for the degradation of carbaryl insecticide in water under UV irradiation. The obtained composite nonwoven exhibited a yellow-gold color and similar thermal and physical characteristics, including fiber size and a narrow size distribution, to the PLA nonwoven. Furthermore, it exhibited superior mechanical properties compared to the PLA nonwoven, particularly in terms of breaking strength. Among the composite nonwovens, the one with the masterbatch added at 10 phr (PLA-2) demonstrated the highest breaking strength. Additionally, it was noteworthy that all ratios of the composite nonwoven displayed excellent carbaryl insecticide decomposition efficiency under UV light, consistently achieving around 40% degradation. Furthermore, these composite nonwovens proved reusable for up to three cycles without a loss in efficiency. These findings suggest that composite nonwovens made from nano-silver coated titanium dioxide photocatalysts and biodegradable polylactic acid hold promise as alternative materials for the decomposition of carbaryl insecticide in natural water sources. [ABSTRACT FROM AUTHOR]

Photocatalytic membranes offer an effective strategy to overcome the difficulties of solid-liquid separation and secondary contamination of powdered photocatalysts. MXene is a 2D material of layered Ti3C2, which is considered to limit electron-hole separation and contribute to photocatalysis. In this work, the etched Ti3C2 MXene was loaded on the surface of ceramic membranes using polydopamine (PDA) as a binder, followed by one-step calcination to produce TiO2 nanoparticles (NPs) in situ. The characterizations supported that the TiO2/Ti3C2 ceramic membranes had high mechanical strength while retaining the layered structure of Ti3C2, which was conducive to the inhibition of electron and hole complexation, improving the photocatalytic performance. Degradation experiments revealed that the material showed enhanced degradation of pharmaceuticals and personal care products (PPCPs) such as ciprofloxacin (CIP), tetracycline (TCN) and ibuprofen (IBP). The LC-MS and toxicity prediction models indicated that the developmental toxicity of CIP degradation products decreased with prolonged photocatalytic reaction, exhibiting no acute toxicity to fish. The MT650 exhibited significantly enhanced water flux properties (320 L/(m2·h)). The TiO2/Ti3C2 ceramic membranes explored in this work are expected to target the treatment of PPCPs with excellent engineering promise. [ABSTRACT FROM AUTHOR]

The preparation of biochar (BC) as a useful substance generated from biomass valorization via pyrolysis has attracted much attention in recent years. Moreover, widespread worries about water pollution and the issues brought on by producing and releasing massive volumes of industrial effluents have sparked research initiatives to examine practical and affordable solutions to these problems. Dyes, heavy metals, and pharmaceutical compounds are the main hazardous pollutants in industrial wastewater. As a result, biochar (BC)/biochar (BC)-based nanocomposites have been presented as a potential alternative to handle wastewater pollution with both adsorption and photocatalytic degradation processes. Such nanocomposite materials benefit from the synergistic effect of adsorption and photocatalysis to attain improved removal of pollutants from industrial wastewater. Therefore, this review aims to describe different preparation methods for biochar and biochar-based nanocomposites. Furthermore, the differences between the adsorption and photocatalytic degradation processes are discussed. BC-based nanocomposites have emerged as promising adsorbents and photocatalysts for wastewater treatment applications. To maximize the efficiency of these processes, an overview of the parameters affecting pollutants removal from wastewater via adsorption and photocatalytic degradation processes is reviewed, where biochar dose, initial pollutant concentration, pH, temperature, time, the presence of different anions, and recycling are discovered to have a significant impact on their performance. Finally, future recommendations and research directions are provided to help shape the applications of BC-based nanocomposites for wastewater treatment applications. This review offers a comprehensive evaluation of the use of biochar as a new environmental material capable of removing pollutants from wastewater. [ABSTRACT FROM AUTHOR]

In this present work, photocatalysts based on a new pyrochlore-type solid solution were prepared using the ceramic method at 1000°C. X-ray diffraction (XRD) analysis shows the existence of a solid solution with pyrochlore structure Bi1.5Sb1.5Zn1–xCuxO7 (0 ≤ x ≤ 1). Scanning Electron Microscope (SEM) images exhibited a slight difference in the external morphology of the samples. The UV-diffuse measurement revealed a change in the absorbance from the UV part for the zinc-rich compound to the visible part for the copper-rich compound. The Energy band gap values were between 3.15 and 1.84 eV. The photocatalytic activity of these prepared mixed oxides was studied for the photo-degradation of the dye Orange II (ORII) as an organic pollutant, in the presence of hydrogen peroxide (H2O2) as an oxidising agent, under sunlight irradiation, by varying different parameters such as the catalysts mass, the oxidant volume, the concentration of the pollutant and the pH. The experimental results obtained by UV-visible spectroscopy revealed that the removal efficiency of ORII increased with increasing the irradiation time for all tested photocatalysts. The pseudo-first-order kinetic model gave the best fit, with the highest correlation coefficients (R2 = 0.99). The results of this study revealed the potential and various advantages of these new efficient photocatalysts. [ABSTRACT FROM AUTHOR]

In this study, we investigated the photocatalytic degradation of Congo red dye using zinc-doped cadmium manganese aluminum ferrite nanoparticles (ZnxCd0.8−xMn0.2Al0.1Fe1.9O4, X = 0, 0.3). Ferrite catalysts were synthesized via a sol–gel method and extensively characterized to understand the impact of Zn doping on their structural, morphological, and textural properties. FTIR, SEM, EDX, and BET analyses confirmed that Zn doping modified the characteristics of the catalyst. Zn doping decreased the crystallite size and lattice parameters, increased the FWHM and density, and shifted the metal–oxygen bond vibration peaks. The SEM images showed that Zn doping refined the particle size and improved the morphology, confirming the incorporation of Zn. The BET analysis revealed that Zn doping enhanced the surface area, pore volume, and pore radius. The undoped photocatalyst possessed a bandgap of 2.8 eV, while Zn-doping led to a narrower bandgap (2.6 eV), consequently enhancing visible light absorption. The Zn-doped catalyst achieved 93.12% Congo red degradation at pH 7, 30 °C, 80 min and concentration of Congo red dye 10 ppm, significantly outperforming the undoped catalyst (62.45%). Zn doping improved charge separation and promoted the generation of reactive oxygen species (ROS), leading to enhanced photodegradation efficiency. Scavenger studies confirmed the crucial role of hydroxyl radicals in the degradation process. Furthermore, the Zn-doped catalyst maintained an 81.03% degradation efficiency even after five consecutive cycles, indicating promising recyclability. These findings highlight the potential of Zn-doped cadmium manganese aluminum ferrite as an efficient and stable photocatalyst for remediation of Congo red-contaminated wastewater. [ABSTRACT FROM AUTHOR]

This study investigates the photocatalytic properties of carbon nanotube (CNT)-supported nitrogen-, cobalt-, and silver-doped zinc oxide (ZnO) synthesized via the solvothermal method. Various characterization techniques, including X-ray photoelectron spectroscopy (XPS), BET surface area analysis, energy-dispersion X-ray (EDX) spectroscopy, UV–visible spectroscopy (UV–Vis), scanning electron microscopy (SEM), X-ray diffraction (XRD), photoluminescence (PL), Fourier transform infrared (FTIR), and transmission electron microscopy (TEM), were employed. Photoluminescence spectroscopy revealed lattice defects and the doping effect on ZnO’s electron–hole recombination. FTIR spectroscopy identified functional groups, and EDX and XPS confirmed the presence of Ag, Co, C, Zn, O, and N. XRD and TEM estimated crystal sizes between 21 and 24 nm. UV–Vis spectroscopy showed a reduced band gap from 3.18 to 2.40 eV. SEM images depicted hexagonal nanoparticle structures. BET analysis showed a Category 4 adsorption isotherm and a pore diameter of 8.527 nm. The nanocomposite ZnO exhibited significant photocatalytic degradation under visible light, achieving 96% and 85% degradation of Congo red and methylene blue dyes, respectively. This study highlights the enhanced photocatalytic performance of CNT-supported nitrogen-, cobalt-, and silver-doped ZnO nanocomposites, suggesting their potential for environmental remediation applications. [ABSTRACT FROM AUTHOR]

The present study uses Adenanthera pavonina L. plant extract to synthesize Y/Fe2O3 nanoparticles in a sustainable and efficient manner. Several physicochemical investigations were performed on the synthesized Y/Fe2O3 to evaluate its structure and morphological characteristics. The high crystallinity of Fe2O3 and decreased crystal size of Y/Fe2O3 were revealed by the XRD study. The formulated Y/Fe2O3 was spherical in shape. Y/Fe2O3 has shown potential photocatalytic activity in the degradation of congo red and brilliant green dyes in the presence of visible light. Degradation efficiency is higher than 90% for both dyes. In addition, the antibacterial activity of Y/Fe2O3 was measured against pathogenic strains of Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Micrococcus luteus, Proteus mirabilis, Pseudomonas putida, Shigella dysenteriae, and Staphylococcus aureus. Y/Fe2O3 showed promising antibacterial activity against all microorganisms. Micrococcus luteus showed a higher zone of inhibition (equal to 35 mm in diameter) than other microorganisms using Y/Fe2O3. Thus, it is established that the green synthesized Y/Fe2O3 nanoparticles are active catalysts for the photocatalytic degradation of hazardous dyes and have antibacterial properties against different bacterial stains. [ABSTRACT FROM AUTHOR]

In this study, the porous graphite phase carbon nitride photocatalyst (P-g-C3N4) is prepared by the CaCO3 template method, and then P-g-C3N4/T-polyethylene terephthalate (T-PET) catalytic fibre is prepared by the padding method. P-g-C3N4 can provide more active sites than g-C3N4 as proved by the Brunauer–Emmett–Teller and the UV–Visible diffuse reflectance test. P-g-C3N4 powder catalyst successfully supports PET fibre as proved by scanning electron microscope, Fourier infrared spectroscopy and X-ray diffraction spectroscopy. The photocatalytic performance of P-g-C3N4/T-PET catalytic fibre is tested by constructing a single hexavalent chromium or hexavalent chromium/organic pollutant binary pollution system. The potential application value of P-g-C3N4/T-PET catalytic fibre is further explored by simulating the complex actual water environment. After five recycles, P-g-C3N4/T-PET catalytic fibre shows good catalytic performance. The mechanism of P-g-C3N4/PET photocatalytic degradation of organic pollutants is proposed through the capture agent experiment and electron paramagnetic resonance spectroscopy. Among them, •O2− is the most important active species of P-g-C3N4 catalytic fibre, which is used for the oxidation of organic pollutants. At the same time, photoelectrons generated by the catalytic fibre are used to reduce hexavalent chromium. The efficiency of P-g-C3N4 to remove pollutants is improved by using PET fibre as a carrier, which not only solves the problem of difficult recovery of powder catalysts but also provides more active sites. [ABSTRACT FROM AUTHOR]

With increasingly serious environmental pollution problems, the development of efficient photocatalytic materials has become a hotspot in current research. This study focused on phosphorus-doped carbon nitride/titanium dioxide (PCT) Z-type heterojunctions, aiming to deeply investigate their photocatalytic degradation and photosensitive antimicrobial properties. A PCT Z-type heterojunction was successfully fabricated using melamine phosphate, cyanuric acid, and titanium dioxide. The structure, morphology, and optical properties of PCT Z-type heterojunctions were explored by FTIR, XRD, XPS, BET, SEM, UV-Vis DRS, TEM, EIS, and PL. A comprehensive and in-depth analysis of the structure, morphology, and optical properties of PCT Z-type heterojunctions was carried out. The photocatalytic degradation experiments revealed that PC3T Z-type heterojunctions exhibited an excellent degradation capability for methylene blue (MB) under visible light. The effect of PC3T on the adsorption–photocatalytic degradation of MB is more than 1.5 times that of a single titanium dioxide and P-doped carbon nitride. In the photosensitive antimicrobial performance study, PC3T reduced the survival rate of E. coli to 7%, after 120 min. Through free radical trapping experiments, it was shown that the hydroxyl radicals and superoxide radicals exerted an influence on the photocatalytic process. This study offers new ideas and approaches to address environmental pollution problems and holds significant theoretical and applied value. [ABSTRACT FROM AUTHOR]

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In this study, we examined how current density, sodium phosphate concentration, and the addition of copper sulfate to the supporting electrolyte affect PEO coatings on pure titanium. The chemical composition, morphology, and optical behavior of PEO coatings were extensively analyzed using scanning electron microscopy (SEM), X-ray diffraction (XRD), and UV–Vis diffuse reflectance spectroscopy (DRS). With an increase in current density from 6 to 18 A/dm2, the coating's pore size enlarges and the rutile phase content within the coatings increases. The coating created at 12 A/dm2 shows the highest photocatalytic activity and triggers a unique three-stage behavior in the voltage-time diagram. Adding 4 g/l of CuSO 4 to the electrolyte resulted in the formation of an unwanted Cu-based precipitates, causing electrolyte instability. To stabilize it, potassium hydroxide was removed, and the base electrolyte concentration was adjusted. To address this issue, potassium hydroxide was eliminated from the supporting electrolyte. Subsequently, the concentration of the base electrolyte was optimized. Also, the synergistic influence of CuSO 4 addition (4 g/l) to the supporting electrolyte at different concentrations of 5, 10, and, 15 g/l of trisodium phosphate on PA was investigated. The superior photocatalytic performance of the optimum coating created in the electrolyte containing 5 g/l trisodium phosphate and 4 g/l CuSO 4 is attributed to its enhanced porous structure, along with the heterojunction between the anatase and rutile phases. These features significantly boost the available surface area and facilitate the efficient separation and transfer of photogenerated charge carriers. Ultimately, a mechanism for MB photodegradation was proposed based on the findings from Mott-Schottky analysis and DRS. [ABSTRACT FROM AUTHOR]

In this study, Ag2CrO4@NiFe-LDH nanoparticles were synthesized by hydrothermal method for photocatalytic degradation of Alizarin Red (AR) dye. Three composites with different molar percentages were prepared, among which 50%Ag2CrO4@50%NiFe-LDH composite was the best sample with a removal rate of 97.1% in AR degradation. Also, the properties, structure, and characteristics of pure Ag2CrO4 and NiFe-LDH and their composites were determined by XRD, FESEM, FTIR, EDX mapping, and UV–visible analyses. It was found that Ag2CrO4@NiFe-LDH composites with the formation of heterogeneous structure of Z-scheme, in addition to increasing the active sites and increasing the specific surface, decrease the recombination rate of pure Ag2CrO4 and NiFe-LDH. Also, the Box–Behnken design technique, which is one of the most common designs used in response surface methodology, was used to optimize the operating conditions and investigate the effect of 4 independent parameters: catalyst amount, solution concentration, pH, and light intensity. The importance of independent parameters and their interactions were determined by ANOVA. By means of numerical optimization, the optimal values of the selected parameters equal to 1.34 g/L of catalyst, concentration of 16.45 mg/L, pH = 10.74, and light intensity of 15.53 W were obtained as optimal conditions with a desirability coefficient of 1.00 and an absorption value of 89.34%. The closeness of adjusted R2 (0.9838) and predicted R2 (0.9507) values show that this model can be successfully used for prediction. [ABSTRACT FROM AUTHOR]

A process for photocatalytically synthesizing hydrogen peroxide while simultaneously degrading organic pollutants is of interest. In this study, a dendritic nanopolymer was synthesized and utilized as a photocatalyst for the production of hydrogen peroxide, which was then used in tandem with the degradation of Tetracycline (TC) and Rhodamine B (Rh B) organic pollutants under a 36 W incandescent bulb. The yield of H2O2 was measured at 8.4 mg g−1 h−1, with photocatalytic degradation rates of 93.90 % for Rh B and 72.92 % for TC. The degradation kinetics of TC and Rh B by the dendritic polymer were found to follow pseudo‐first‐order kinetics, and a higher affinity for degradation was observed for Rh B. The photocatalytic degradation mechanism of TC in a Fenton‐like system was attributed to an oxidation system involving hydrogen peroxide and ferrous ions. [ABSTRACT FROM AUTHOR]

For the first time, a novel catalyst named Dy2EuSbO7 was successfully synthesized via the high-temperature solid-state sintering method (HTSSM). Dy2EuSbO7/ZnBiDyO4 heterojunction photocatalyst (DZHP) was fabricated through the HTSSM for degrading chlorpyrifos (CPS) in the pesticide wastewater under visible light irradiation (VSLID). Under VSLID, DZHP could effectively degrade CPS in pesticide wastewater. The experimental outcomes suggested that the kinetic curve with the Dy2EuSbO7/ZnBiDyO4 heterojunction (DZH) as a photocatalyst for the reduction of CPS under VSLID conformed to the first-order kinetics (FOKT). After VSLID of 156 min, the photocatalytic degradation (PTD) removal rate of CPS using DZH as photocatalyst was 1.12 times, 1.21 times, or 2.96 times that using Dy2EuSbO7 as a photocatalyst, ZnBiDyO4 as a photocatalyst, or nitrogen-doped titanium dioxide as a photocatalyst. After VSLID of 156 min for four cycle degradation tests (FCDTS) with DZH as a photocatalyst, the removal rate of CPS reached 98.78%, 97.66%, 96.59%, and 95.69%, respectively. Above results indicated that the DZHP possessed high stability. Experiments with the addition of trapping agents showed that hydroxyl radicals (•OH) owned the strongest oxidative removal ability for degrading CPS compared with superoxide anions (•O2−) or holes (h+). The oxidation capacity of three oxidation radicals for eliminating CPS was ranked in the ascending order as follows: h+ < •OH < •O2−. Lastly, the possible degradation pathway and degradation mechanism of CPS were discussed in detail. A visible light responsive heterojunction catalyst with high catalytic activity and a photocatalytic reaction system which were capable of efficiently removing toxic organic pollutants from pesticide wastewater were obtained. [ABSTRACT FROM AUTHOR]

Based on the principle of molecular design and self-assembly, a novel rare earth based arsenotungstate was obtained by introducing rare earth LaⅢ ions into the lacunary polyoxotungstates clusters with vacancy structure by one-pot method with Na2 WO4 ·2H2 O, NaAsO2 and LaCl3 ·6H2 O as the main materials. The structure and composition of this complex was confirmed by single-crystal X-ray diffraction, X-ray powder diffraction (PXRD), infrared spectroscopy (IR) and so on. The single crystal X-ray diffraction results show that the complex is in the monoclinic system, C2/c space group, and with the cell parameters of a =3.595 56(14) nm, b =1.222 48(4) nm, c =2.247 34(9) nm, β = 117.117 0(10)°, V =8.792 3(6) nm3, Z =4. The molecular formula of this compound is [(CH3)2 NH2]8 H3. 56 [{LaO(H2 O)2 }{WO(H2 O)}{W0. 24 (H2 O)2 } {AsW9 O33 }2]. And the polyoxoanion [{LaO(H2 O)2 }{WO(H2 O)}{W0. 24 (H2 O)2 }{AsW9 O33 }2]11. 56 - shows a novel sandwich type structure, which can be simply described as two trilacunary Keggin type{AsW9 O33 } units are linked by a {LaO(H2 O)2 } segment, a {WO(H2 O)} segment and a {W0. 24 (H2 O)2 } segment. Catalytic degradation property of this compound for Rhodamine-B was further inverstigated. The results demonstrate that the compound shows good photocatalytic activity under the condition of 300 W Hg lamp irradiation, and the degradation efficiency reaches to 74%. [ABSTRACT FROM AUTHOR]

Utilising the solution combustion technique, nanocrystalline photocatalysts that included both pristine TiO2 and doped TiO2 with various La (III) dopant percentages (1, 3, 5, and 7 mol%) were created. Different methods, including thermal analysis, high resolution-transmission electron microscopy (HR-TEM), X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FT-IR), and field-emission scanning electron microscopy (FE-SEM), were used to investigate the prepared nanostructures. The XRD results indicated the anatase form and the crystalline nature of the products (pristine and doped TiO2) in the size range of a crystallite (5–16.5) nm. The photocatalytic assessment of the prepared nano-photocatalysts was carried out by crystal violet (CV) decolourisation under ultraviolet (UV) light. The findings revealed that 3% La-TiO2 showed the highest degradation efficiency (95.98%) in 70 min with a pseudo-first-rate constant of k = 4.73 × 10−2 min−1, compared to pristine TiO2 and the other TiO2 nanostructures with various La (III) dopant ratios. [ABSTRACT FROM AUTHOR]

The construction of p–n heterojunction is critical to reduce the electron–hole recombination rate and broaden the light absorption edge of photocatalysts. In this study, we successfully synthesize the Cu2O/CeO2 p–n heterojunctions through a rapid, simple, and environmentally friendly sonochemical method without any additional oxidants or elevation of the temperature and pressure. The prepared Cu2O/CeO2 heterojunction shows excellent adsorption of light, low electronic transfer resistance, and higher electron transfer efficiency. Under the irradiation of visible light, the as‐prepared Cu2O/CeO2 heterojunction exhibits exceptional capability for the degradation of methylene blue as well as outstanding reusability. The photo‐generated h+ is found to have a significant influence on the photocatalytic antibacterial of the as‐prepared Cu2O/CuO2 heterojunction under visible‐light irradiation and the sterilization rate toward Staphylococcus aureus and Escherichia coli of our samples can achieve up to 100%. Our work provides a green and rapid way to produce Cu2O/CeO2 p–n heterojunctions with enhanced photocatalysis. [ABSTRACT FROM AUTHOR]

Streptomycin was chosen as the test species, and MgO@graphene nanocomposites were created and assessed for their catalytic activity towards the breakdown of 4-NP. As a new catalyst with strong catalytic activity and good stability, MgO@graphene was used. It was discovered that this catalyst's catalytic activity was much increased in an acidic environment. It is suggested that the degradation mechanism is caused by MgO@graphene nanocomposites reacting with dissolved oxygen. This further demonstrates the obvious significance of graphene in serving as the MgO nanocatalyst's support. XRD results indicated that the majority of G species in MgO@ (0.25 g) G more strongly interacted with the MgO surface. The doped catalyst MgO@ (0.25 g) G reached its steady state activity faster than the other catalysts. The degree of MgO@G interaction decreased in the following S4 > S mix > S 2 > S 3 > S 1 > S5 > S 6 > S o . High degradation rate constants were found, and the amounts of streptomycin and 4-nitrophenol vary exponentially over time. It was demonstrated that, in most situations, the pseudo-first- order equation fits the degradation kinetics. Hence, in degrading systems, MgO NPs@Graphene nanostructures are thought to be a very effective and promising catalyst. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the performance of the Pd@TMU-16 to act as a photocatalyst in degrading the Acid Red 88 (AR88) dye from an aqueous solution, via photocatalysis process, using UV irradiation. The synthesis of this catalyst was performed under conditions of thermal solvent and its characteristic parameters were confirmed using the XRD, Band gap, SEM, BET, pHPCZ, and FTIR methodologies. The influence exerted by the operative parameters on the AR88 degradation, which included the pH, reaction time, radiation intensity, catalyst mass, and initial dye concentration was examined. At the optimum condition of photocatalysis and utilising only 0.75 g of Pd@TMU-16, total degradation of 10 mg/L dye concentration was performed. From the kinetic studies, the dye degradation indicated that it was similar to the pseudo-first-order model, and the dye degradation mechanism had taken place through the hydroxyl (•OH) and superoxide radicals (•O⁻₂). The adsorbent reusability was also studied, and from the results it was evident that the 18% decrease observed after six consecutive cycles of catalyst use, clearly indicated its stability. For radiation intensities of 8, 15, 24, and 36 W, the Energy Consumed per m3 of the treated wastewater was found 20.2, 28.8, 34.1, and 36.9 kWh, respectively. From these results, namely the low energy gap (2.3 eV) and high degradation capacity, it was evident that the Pd@TMU-16 can be useful, under UV light, as a powerful catalyst in the elimination of dyes and other organic contaminants from polluted aqueous media. [ABSTRACT FROM AUTHOR]

In this study, a novel photocatalyst comprising graphitic carbon nitride (g-C3N4) and tungsten oxide (WO3) in different weight ratios was fabricated through a facile synthesis method. The synthesized nanocomposites were characterized using various techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and UV–vis spectroscopy to elucidate their structural and optical properties. The photocatalytic performance of the g-C3N4/WO3 nanocomposite was evaluated for Rhodamine (RhB) degradation under visible light irradiation. Remarkably, the 3 wt % g-C3N4/WO3 nanocomposite exhibited a superior degradation efficiency of 96% (rate constant ~ 0.02714 min−1) compared to pure g-C3N4 and WO3. The major role was played by both holes (h+) and superoxide anion radicals (•O2−) in the degradation process. This performance is attributed to the synergistic effect between the two components, which facilitated efficient charge separation leading to decreased recombination of photo-generated electron–hole pairs, and improved light absorption. Additionally, the optimized nanocomposite was employed for electrochemical detection of 2-nitrophenol (2-NP), showcasing remarkable sensitivity (limit of detection ~ 0.22 µM) and selectivity towards 2-NP. This positions it as a promising candidate for environmental monitoring applications. In summary, this study underscores the potential of the g-C3N4/WO3 nanocomposite in wastewater treatment as a visible light photocatalyst, alongside its utility in electrochemical sensing of organic pollutants. [ABSTRACT FROM AUTHOR]

[Display omitted] In this study, AgBr/Bi 4 Ti 3 O 12 /Bi 2 Sn 2 O 7 (ABr/BTO/BSO) composites were successfully synthesized to facilitate multi-channel fast charge transfer. This directs the charge carriers to travel along multichannel pathways and suppresses carrier recombination. The mechanisms underlying charge transfer in the dual S-scheme heterojunction composites were elucidated using density functional theory (DFT) and in situ irradiated X-ray photoelectron spectroscopy (ISI-XPS). Furthermore, electron spin resonance (ESR) and burst experiments verified h+, ·O 2 - , and ·OH as the primary active species in the catalytic process. The ABr/BTO/BSO composites demonstrated exceptional photocatalytic redox capabilities, completely degrading rhodamine B (RhB) and achieving degradation rates of 77.21% for tetracycline (TC) and 81.04% for Cr (VI). Both experimental and theoretical analyses confirmed the intrinsic efficacy of photo-induced electron movement within the composites. This research introduces innovative design concepts and strategies for the advanced exploration of electron channel transfer in ABr/BTO/BSO ternary composites and the development of novel composite photocatalytic systems. [ABSTRACT FROM AUTHOR]

The release of toxic dyes into water effluents by various industries has become a global concern. Therefore, developing novel, straightforward, and economically viable methods or materials for purifying these hazardous pigments is imperative. This study aims to synthesize copper oxide nanoparticles (CuO-NPs) through a green route using Vicia faba leaf extract. UV-Vis spectroscopy reveals an absorption band ranging from 200 nm to 300 nm, with a major absorption peak at 212 nm and an energy band gap of 5.29 eV. FTIR, SEM, EDX, and XRD techniques characterise the synthesised CuO nanoparticles. FTIR analysis identifies functional groups including hydroxyl (OH), aromatic C-H, C=C stretching, carbonyl (C=O), and Cu-O stretching vibrations. Scanning electron microscopy reveals flower-like particles, while EDX analysis confirms the formation of CuO nanoparticles. The XRD pattern indicates a crystalline structure with an average particle size of 27.44 nm. A plot of (αhv)² versus photon energy (hv) was generated to determine the energy band gap, yielding a value of 5.29 eV. Rhodamine-B and methylene blue (MB) dyes were employed to evaluate the photocatalytic degradation of the synthesized CuO-NPs, resulting in correlation coefficients of 0.7154and 0.9702, respectively. Furthermore, the rate constants of these dye reactions were found to be 0.0406min-1 and0.0343 min-1. [ABSTRACT FROM AUTHOR]

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This study investigates the effect of iron-modified nano-TiO2, using the co-precipitation method with different concentrations of FeCl3 (0.1, 1, and 10%), to improve its photocatalytic properties for outdoor applications. To this end, modified and unmodified nano-TiO2 were characterized using different techniques. The optical properties were characterized by diffuse reflectance spectroscopy (DRS) followed by band gap calculation. X-ray diffraction (XRD) was used to analyze the crystalline structure. Chemical and morphological characterization were carried out using energy-dispersive X-ray spectroscopy (EDS) and scanning electron microscopy (SEM). The photocatalytic activity was investigated by decolorizing Rhodamine B aqueous solutions under similar sunlight irradiation. The results indicate that the modification improved light absorption in the UV range for all iron concentrations; however, only the concentration of TiO2: FeCl3 (10%) shifted the absorption to the visible region. Also, including Fe3⁺ in TiO2 decreased the band gap energy from 3.14 to up to 2.80 eV. There were variations in crystallite size from 21.13 to up to 40.07 nm. The nano-TiO2 morphology analysis showed that it did not change after iron modification. EDS showed an FeCl3 peak only at higher concentrations (10%). In addition, the 0.1% Fe-modified TiO2 exhibited the highest activity in the photocatalytic process, with an efficiency of 95.23% after 3 h of irradiation. [ABSTRACT FROM AUTHOR]

Herein, this study has examined the influence of Zn2+ sources during a biogenic-mediated pathway to synthesize ZnO nanoparticles with highly desirable solar-responsive catalytic properties. Salts of nitrate, acetate and chloride have been utilized. The ZnO powders underwent characterization using diverse analytical tools, including XRD, FTIR, Raman, BET, SEM, TEM with EDS/elemental mapping and UV-vis absorption/emission spectroscopic analyses. Accordingly, precursors have proved to affect crystallinity, morphology, surface characteristics, optical properties and the photocatalytic degradation of methylene blue (MB) model pollutant. It was observed that ZnO derived from zinc acetate precursor (Z-AC NPs) exhibits very fast photocatalytic degradation of MB at pH 11 with superior kinetic estimates of 0.314 min−1 and t1/2 = 2.2 min over many of recent reports. In contrast, the chloride precursor is not recommended along with the employed biogenic route. The intriguing findings could be directly correlated to the decreased crystal size, augmented surface area, the hexagonal morphology of the crystals, high potency in absorbing visible photons, high efficacy in separating photogenerated charge carriers and producing high amounts of •OH radicals. Further testing of Z-AC NPs in photocatalytic remediation of water samples from Dumat Aljandal Lake in Aljouf, Saudi Arabia, contaminated with MB and pyronine Y (PY) dyestuffs, showed high dye photodegradation. Therefore, this work could lead to an extremely fast avenue for decontaminating wastewater from hazmat dyestuff. [ABSTRACT FROM AUTHOR]

Photocatalysis based on titanium dioxide (TiO2) has become a promising method to remediate industrial and municipal effluents in an environmentally friendly manner. However, the efficiency of TiO2 is hampered by problems such as rapid electron–hole recombination and limited solar spectrum absorption. Furthermore, the sensitization of TiO2 through heterojunctions with other materials has gained attention. Vanadium, specifically in the form of ammonium vanadate ((NH4)2V3O8), has shown promise as a photocatalyst due to its ability to effectively absorb visible light. However, its use in photocatalysis remains limited. Herein, we present a novel synthesis method to produce lamellar (NH4)2V3O8 as a sensitizer in a supramolecular hybrid photocatalyst of TiO2–stearic acid (SA), contributing to a deeper understanding of its structural and magnetic characteristics, expanding the range of visible light absorption, and improving the efficiency of photogenerated electron–hole separation. Materials, such as TiO2–SA and (NH4)2V3O8, were synthesized and characterized. EPR studies of (NH4)2V3O8 demonstrated their orientation-dependent magnetic properties and, from measurements of the angular variation of g-values, suggest that the VO2+ complexes are in axially distorted octahedral sites. The photocatalytic results indicate that the 2D/2D heterojunction layered TiO2/vanadate at a ratio (1:0.050) removed 100% of the methylene blue, used as a model contaminant in this study. The study of the degradation mechanism of methylene blue emphasizes the role of reactive species such as hydroxyl radicals (•OH) and superoxide ions (O2•−). These species are crucial for breaking down contaminant molecules, leading to their degradation. The band alignment between ammonium vanadate ((NH4)2V3O8) and TiO2–SA, shows effective separation and charge transfer processes at their interface. Furthermore, the study confirms the chemical stability and recyclability of the TiO2–SA/(NH4)2V3O8 photocatalyst, demonstrated that it could be used for multiple photocatalytic cycles without a significant loss of activity. This stability, combined with its ability to degrade organic pollutants under solar irradiation, means that the TiO2–SA/(NH4)2V3O8 photocatalyst is a promising candidate for practical environmental remediation applications. [ABSTRACT FROM AUTHOR]

Organic dyes are stable and persistent toxic compounds in the aquatic environment that are refractory to decompose by removal methods such as physico-chemical, optical and biological. Their presence in the aquatic media threatens human and wildlife. Herein, ZnO nanoparticles (NPs) due to good chemical durability, low cost and good photocatalytic performance was anchored on biochar (ZnO@biochar) nanocomposites were synthesized towards activation of peroxymonosulfate (PMS) for the photocatalytic removal of methyl orange (MO) dye. Several methods were used to characterization of the nanocomposites including FESEM, XRD, PL, EDS, FT-IR spectroscopy, and N2 adsorption/desorption. The results of the techniques demonstrated that the well-dispersed ZnO NPs were loaded onto the biochar surface. According to the particle size distribution graph, the average particle size of 64 nm was obtained for the ZnO NPs. BET analyzes showed that pore volume, the specific surface area (SSA) and average pore size of the synthesized nanocomposite increased. The survey of effective operational parameters indicated that the highest photocatalytic activity for MO removal was in the pH 3 of solution, 5 ppm initial dye concentration, 30 mg ZnO/biochar nanocomposite, and 20 mg PMS dose under LED-50W lamp irradiation (97.03% in the reaction time of 80 min). During the process, the reduction of the total organic carbon (TOC) contents and chemical oxygen demand (COD) were observed. Moreover, the MO degradation kinetics under optimal operating conditions were determined. It is concluded that the ZnO@biochar nanocomposite/PMS process was an efficient degradation method for the decomposition of the dye pollutant. [ABSTRACT FROM AUTHOR]

In recent years, metal oxide nanoparticles synthesized using environmentally friendly and inexpensive methods have attracted attention due to their potential applications in the fields of medicine, catalysts, ceramics drugs, and optics. Therefore, this research reports the biosynthesis of the pure ZnO and Ag-doped ZnO nanoparticles using Hedera colchica (H. colchica) extract (ZnO/Ag@HC NPs) and using them for antibacterial, anticancer, and catalytic activities. The green synthesized ZnO/Ag@HC NPs were characterized using various techniques, including HPLC, UV–Vis, DLS, TEM, EDS, FTIR DRS, BET, FESEM, and XRD. ZnO/Ag@HC NPs were observed to have spherical and oval-like morphologies in the FESEM and TEM analysis images, with an average particle size of 30–40 nm. Penicillin G (PNG) as the model pollution was examined to assess the photocatalytic activity of the biosynthesized nanoparticles. The influence of critical parameters such as nanocatalyst dosage, pH and light source were investigated to achieve the optimum degradation of penicillin G. The results revealed that ZnO/Ag@HC NPs exhibited a higher photocatalytic performance (98.4%) than pure ZnO NPs in the degradation of the penicillin G antibiotic (87.5%). Furthermore, the antibacterial performance of ZnO/Ag@HC NPs was investigated against eight strains. The highest antibacterial activity was observed against A. baumannii, S. aureus, and E. faecalis with MIC values of 0.44 μg/ml. The anticancer activity of ZnO/Ag@HC NPs and pure ZnO NPs was conducted on acute lymphoblastic leukemia NALM-6 and normal fibroblast cells using the MTT assay at various concentrations (6.25–1000 µg/ml). The results of pure ZnO NPs and ZnO/Ag@HC-treated NALM-6 cells showed IC50 values of 50 and 25 μg/ml, respectively. These findings suggest the suitability of ZnO/Ag@HC NPs for antibiotic degradation, antibacterial and anticancer drug development. [ABSTRACT FROM AUTHOR]

The emergence of antimicrobial resistance due to antibiotics in the environment presents significant public health, economic, and societal risks. This study addresses the need for effective strategies to reduce antibiotic residues, focusing on ciprofloxacin degradation. Magnetic iron oxide nanoparticles (IO NPs), approximately 13 nm in size, were synthesized and functionalized with branched polyethyleneimine (bPEI) to obtain a positive charge. These IO-bPEI NPs were combined with negatively charged titanium dioxide NPs (TiO2@CA) to form magnetically photocatalytic IO-TiO2 nanocomposites. Characterization techniques, including X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), infrared spectroscopy (IR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), electrokinetic measurements, and a vibrating sample magnetometer (VSM), confirmed the successful formation and properties of the nanocomposites. The nanocomposites exhibited a high specific surface area, reduced mobility of photogenerated charge carriers, and enhanced photocatalytic properties. Testing the photocatalytic potential of IO-TiO2 with ciprofloxacin in water under UV-B light achieved up to 70% degradation in 150 min, with a degradation rate of 0.0063 min−1. The nanocomposite was magnetically removed after photocatalysis and successfully regenerated for reuse. These findings highlight the potential of IO-TiO2 nanocomposites for reducing ciprofloxacin levels in wastewater, helping curb antibiotic resistance. [ABSTRACT FROM AUTHOR]

The dyeing process in textile industries has significant environment implication, primarily due to the release of a large amount of water effluents. Photocatalyst is a perennially effective technique used for the degradation of toxic, low- biodegradable hazardous effluents from water bodies. This method is highly selective, cost-effective, straightforward synthesis, and environmentally friendly process. Semiconductor metal oxides-based photocatalysts have gained attraction due to their superior properties including less toxicity and environment applications. However, their widespread implementation has diminished because of the poor photocatalytic activity in the visible region. To address this limitation, incorporating a conducting polymer particularly Polyaniline, has proven more effective. The enhanced charge-carrying capacity and ability to change the optical band gap makes the semiconductor more efficient for the degrading the organic effluents from the water bodies. This review primarily focuses on degradation of poisonous dyes present in textiles wastewater, using the polyaniline-semiconductor nanocomposite as a photocatalyst material. [ABSTRACT FROM AUTHOR]

In recent years, environmental pollutants have become more hazardous to both human health and eco-systems. One potential method for cleaning up the environment is eco-friendly semiconductor photocatalysis. There are several types of mechanism associated with semiconductor photocatalysis, in that, Step-scheme (S-scheme) photocatalysis (SSPC)grabbed plenty of interest in the domain of developing and transforming solar fuel due to their effective charge spatial separation and robust redox capabilities. Herein, this article highlights and summarizes the most recent advancements in S-scheme heterojunctions photocatalysis (SSHJPC); also, briefly encapsulate the process, reaction principle, Mechanism, Synthesis strategies, Frontier characterization techniques and their applications in solar energy conversion. Finally, conclusions are drawn and future prospects for solar energy conversion issues are presented. [ABSTRACT FROM AUTHOR]

The green synthesis of metal oxide nanoparticles (NPs) offers an alternative to chemical procedures, which can be harmful to human health due to exposure to hazardous substances and harsh synthesis conditions. The following work synthesized titanium dioxide nanoparticles (TiO2 NPs) using a green synthesis method. As a precursor, food-grade TiO2 was used with blueberry extract. This approach makes the process safer, cheaper, and simpler, requiring minimal effort to achieve effective TiO2 NP synthesis. The TiO2 NP characterization was performed by solid-state techniques, such as Ultraviolet-visible (UV-Vis) spectroscopy, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). According to the XRD diffractograms, TiO2 NPs were obtained in the anatase phase with incidence peaks of 25.28 (101). TEM confirmed their pseudo-spherical shape with an average size of 170 nm. The 3.2 eV bandgap of TiO2 NPs enables UV absorption, making them ideal for efficient photocatalytic degradation under sunlight. On the other hand, the photocatalytic activity of TiO2 NPs was examined using malachite green (MG) dye as a pollutant model under direct sunlight. After 30 min, a degradation of 94% was achieved. The kinetic analysis identified parabolic diffusion and modified-Freundlich kinetics as primary mechanisms, emphasizing diffusion and adsorption in electron transfer. The main reactive oxygen species (ROS) involved in the photodegradation of MG dye were h+ and OH•. [ABSTRACT FROM AUTHOR]

Wastewater containing phenolic organic compounds, such as phenol, produced during industrial manufacturing processes, poses a significant threat to aquatic ecosystems and crops. Photocatalytic technology is considered the most promising approach to water treatment due to its efficiency and eco-friendly advantages. Compared to other photocatalysts, Bi-based oxides are more efficient due to their unique layered structure, which allows for photocatalytic reactions to occur between layers. This review introduces the synthesis methods of various bismuth-based multi-element oxides and their efficiency in the photocatalytic decomposition of phenol. The effects of elemental doping, defect introduction, and heterojunction construction on the catalytic performance and structure of Bi-based oxides are discussed. The mechanisms for the photocatalytic degradation of phenol over different materials are also summarized and discussed. [ABSTRACT FROM AUTHOR]

A highly water‐soluble and fluorescent N,S‐doped carbon dots/europium (N,S‐CDs/Eu) was successfully synthesized via a secondary hydrothermal method. This involved surface modification of N,S‐CDs derived from sunflower stem pith (SSP) with europium ions (Eu3+) doping. When excited within the range of 400–470 nm, N,S‐CDs/Eu exhibited a stable and broad optimal emission wavelength ranging from 505 to 540 nm. Notably, the photoluminescence quantum yield (PLQY) of N,S‐CDs/Eu is 31.4%, significantly higher than the 19.5% observed for N,S‐CDs. Additionally, by dissolving N,S‐CDs/Eu into polyvinyl alcohol (PVA), a uniform fluorescent anti‐counterfeiting ink can be prepared. The N,S‐CDs/Eu/TiO2 composite demonstrates excellent photocatalytic degradation ability towards the organic dye methylene blue (MB). N,S‐CDs/Eu has potential in the field of fluorescent inks and photocatalysis due to its simple and efficient preparation and excellent properties. [ABSTRACT FROM AUTHOR]

Combining molecular imprinting technique with titanium dioxide (TiO2) photocatalysis technique can improve the degradation ability and selectivity of TiO2 nanoparticles towards pollutants. In this work, methyl orange-imprinted polysiloxane particles (MIPs) were synthesized using TiO2 as matrix and silane as functional monomers. The adsorption capacity (Qe) of MIPs was 20.48 mg·g−1, while the imprinting efficiency (IE) was 3.4. Such MIPs exhibited stable imprinting efficiencies and adsorption efficiencies towards methyl orange (MO) in the multi-cycle stability test. Photocatalytic degradation performances of both MIPs and non-imprinted polysiloxane particles (NIPs) were investigated. Compared with NIPs, MIPs exhibited better photocatalytic degradation performance towards MO, with the degradation efficiency of 98.8% in 12 min and the apparent rate constant (Kobs) of 0.077 min−1. The interaction between silane and MO was also studied through molecular dynamics simulation. This work provides new insights into the use of silane for the synthesis of MIPs as well as the molecular imprinting technique for applications in the field of TiO2 photocatalysis. [ABSTRACT FROM AUTHOR]

The synthesis of high‐efficiency magnetic composite photocatalyst by doping magnetic cobalt ferrite and compounding single semiconductor photocatalyst is a promising strategy to improve the oxidation ability of photocatalytic systems. In this paper, CoFe1.95Dy0.05O4 (CFDO) was prepared by doping Dy element into magnetic CoFe2O4, and Ag2S (AS)/CFDO with high‐efficiency magnetic photocatalyst was synthesized by compounding AS with CFDO as the substrate. The photocatalytic samples were characterized by different advanced characterization methods, and their photocatalytic degradation of methylene blue (MB) was studied. The results show that AS/CFDO exhibits higher visible light response, excellent photogenerated charge separation ability and migration efficiency, and excellent catalytic performance in the catalytic degradation system. The photocatalytic activity of AS/CFDO was the highest, and its photocatalytic degradation kinetic constant K was 2.48 and 1.54 times that of AS and CFDO, respectively. In addition, the catalyst contained in the catalytically contaminated solution can be effectively separated by an external magnetic field to achieve multiple cycles of degradation and recycling. The cyclic degradation experiments showed that AS/CFDO exhibited high degradation stability during the photodegradation process. After the fifth reuse, the degradation efficiency was still more than 88.0%. Finally, the possible photocatalytic mechanism of the samples was discussed. Therefore, this work provides an effective solution for the construction of photocatalysts with high efficiency, magnetic recovery, and cyclic degradation stability and avoids the secondary pollution of catalysts to organic wastewater. It is of great significance to create an environmentally friendly catalytic method for efficient cyclic degradation of organic wastewater. [ABSTRACT FROM AUTHOR]

Cerium‐doped zinc oxide (Ce‐ZnO) nanocones with cerium concentrations of 0, 0.5, 1, and 2 % were synthesized using a sol‐gel method. Their effectiveness as photocatalysts for degrading dyes such as Rhodamine B (RhB), Methylene Orange (MO), and Methylene Violet (MV) was evaluated. The optical and structural properties, particle size distribution, and morphology of these nanocones were examined using X‐ray diffraction (XRD), scanning electron microscopy (SEM), and ultraviolet‐visible (UV‐Vis) spectrophotometry. XRD results confirmed that the nanocones were highly crystalline with a hexagonal wurtzite structure, and a noticeable blue shift was observed in the Ce‐doped ZnO nanocones compared to pure ZnO. The photocatalytic performance under UV exposure showed that cerium doping significantly improved the degradation of RhB, MO, and MV. Notably, ZnO nanocones doped with 1 % cerium exhibited the highest photocatalytic efficiency, achieving 100 % degradation of RhB within 60 minutes. Additionally, 1 % Ce‐ZnO nanocones demonstrated degradation efficiencies of 86.3 % for MO and 74.9 % for MV within the same time frame. [ABSTRACT FROM AUTHOR]

This study focuses on enhancing the properties of kaolin (Kao) clay by incorporating Zinc oxide nanoparticles (ZnO NPs) and further functionalizing with agar biopolymer, resulting in the formation of Agar/Kao@ZnO nanocomposite (NC). The synthesized material underwent comprehensive composition, structure, surface, and optical properties analysis to confirm the formation. The material was evaluated as a photocatalyst for the degradation of 2,4‐dinitrophenol (DNP) under visible light irradiation. The optimized conditions for the photocatalytic degradation of DNP were determined as irradiation time 50 minutes, pH 4, catalyst dose 20 mg, and DNP concentration of 25 mg L−1, resulting in degradation efficiency of 99.63%. Trapping experiment validated the significant role of hydroxyl (•OH) radicals as reactive oxidant species (ROS) in the degradation of DNP in the presence of visible light. Through four consecutive cycles of reusability experiments, it was confirmed that the synthesized material is highly stable and efficient for DNP degradation. [ABSTRACT FROM AUTHOR]