Search Results (1,610)

In this study, a novel method for the high-performance treatment of oily wastewater was introduced using a tungsten (VI) oxide (WO₃)/MXene composite membrane based on poly (arylene ether sulfone) (PAES). Composite membranes were fabricated with superhydrophilic (SH) and superoleophobic (SO) characteristics, which allow for the high-performance treatment of oily wastewater. The fabricated composite membrane can also photodegrade organic types of pollutants with just a short period of UV, enabling self-cleaning and anti-fouling properties. Moreover, the comprehensive characterization of the composite membrane through FTIR, SEM, and XRD analyses yielded valuable insights. The FTIR analysis revealed the characteristic peaks of WO₃, MXene, PAES, and the synthesized composite membrane, providing essential information on the chemical composition and properties of the materials. The XRD results demonstrated the crystal structures of WO₃, MXene, PAES, and the synthesized composite membrane, further enhancing our understanding of the composite membrane. Additionally, the SEM images illustrated the surface and cross-section of the fabricated membranes, highlighting the differences in pore size and porosity between the PAES membrane and the WO₃–MXene composite membrane, which directly impact permeate flux. The study showed that the composite membrane had a remarkable recovery time of only 0.25 h, and the efficiency of the separation process and water flux recovered to 99.98% and 6.4 L/m².h, respectively. The joint influence of WO₃ and MXene on composite membranes degraded contaminants into non-polluting substances after sunlight irradiation. This process effectively solves the treatment performance and decrease in permeate flux caused by contamination. The technology is membrane-based filtration, which is a simple and advanced method for treating polluted water. This innovative work offers promising solutions to address water pollution challenges and holds potential for practical applications from a self-cleaning and anti-fouling point of view. Full article

The degradation of organic dyes poses a significant challenge in achieving sustainable environmental solutions, given their extensive usage across various industries. Iron oxide (Fe₂O₃) nanoparticles are studied as a reliable technique for remediating dye degradation. The objective of this research is to improve methods of nanomaterial-based environmental remediation. The solvothermal technique is used to synthesize carbon-modified Fe₂O₃ nanoparticles that exhibit the capability to modify their size morphology and increase reactivity, and stability for MO photodegradation. Their inherent qualities render them highly advantageous for biomedical applications, energy storage, environmental remediation, and catalysis. The mean crystallite size of the modified Fe₂O₃ nanoparticles is approximately 20 nm. These photocatalysts are tested for their ability to degrade methyl orange (MO) under Visible light radiation and in presence of hydrogen peroxide reagent. The optimal degradation efficiency (97%) is achieved with Fe₂O₃@C in the presence of H₂O₂ by meticulously controlling the pH, irradiation time, and photocatalyst dosage. The enhanced photocatalytic activity of the Fe₂O₃@C nanoparticles, compared to pure Fe₂O₃, is attributed to the conductive carbon layer, which significantly reduces electron-hole recombination rates. To summarize, Fe₂O₃@C nanoparticles not only offer a promising technique for the degradation of MO dye pollutants but also have an advantage for environmental remediation due to their increased stability and reactivity. Full article

“Core/shell” composites are based on a ferrite core coated by two layers with different properties, one of them is an isolator, SiO₂, and the other is a semiconductor, TiO₂. These composites are attracting interest because of their structure, photocatalytic activity, and magnetic properties. Nanocomposites of the “core/shell” МFe₂O₄/SiO₂/TiO₂ (М = Zn(II), Co(II)) type are synthesized with a core of MFe₂O₄ produced by two different methods, namely the sol-gel method (SG) using propylene oxide as a gelling agent and the hydrothermal method (HT). SiO₂ and TiO₂ layer coating is performed by means of tetraethylorthosilicate, TEOS, Ti(IV) tetrabutoxide, and Ti(OBu)₄, respectively. A combination of different experimental techniques is required to prove the structure and phase composition, such as XRD, UV-Vis, TEM with EDS, photoluminescence, and XPS. By Rietveld analysis of the XRD data unit cell parameters, the crystallite size and weight fraction of the polymorphs anatase and rutile of the shell TiO₂ and of the ferrite core are determined. The magnetic properties of the samples, and their activity for the photodegradation of the synthetic industrial dyes Malachite Green and Rhodamine B are measured in model water solutions under UV light irradiation and simulated solar irradiation. The influence of the water matrix on the photocatalytic activity is determined using artificial seawater in addition to ultrapure water. The rate constants of the photocatalytic process are obtained along with the reaction mechanism, established using radical scavengers where the role of the radicals is elucidated. Full article

The excessive use of pesticides has led to the harmful contamination of water reservoirs. Visible-light-driven photocatalysis is one of the suitable methods for the removal of pesticides from water. Herein, the development of CBO (Co₃O₄-Bi₂O₃) as a heterogeneous catalyst for the visible light-assisted degradation of Fipronil and Acetochlor pesticides is reported. After synthesis via coprecipitation using cobalt (II) nitrate hexahydrate (Co(NO₃)₂·6H₂O), bismuth (III) nitrate pentahydrate (Bi(NO₃)₃·5H₂O) and sodium hydroxide (NaOH) as precursor materials, the prepared CBO was characterized using advanced techniques including XRD, EDS, TEM, SEM, FTIR, and surface area and pore size analysis. Then, it was employed as a photocatalyst for the degradation of Fipronil and Acetochlor pesticides under visible light irradiation. The complete removal of Fipronil and Acetochlor pesticides was observed over CBO photocatalyst using 50 mL (100 mg/L) of each pesticide separately within 120 min of reaction. The reaction kinetics was investigated using a non-linear method of analysis using the Solver add-in. The prepared CBO exhibited a 2.8-fold and 2-fold catalytic performance in the photodegradation of selected pesticides than Co₃O₄ and Bi₂O₃ did, respectively. Full article

Oxygen is crucial for life, but its reactive species, like free radicals, can damage health and accelerate aging. Antioxidants from natural and synthetic sources mitigate these effects. Kanjiža Spa’s mineral-rich thermal water is renowned for its therapeutic benefits and potential in eco-friendly pharmaceuticals and cosmetics. Hence, the utilization of mineral water in pharmaceutical and cosmetic applications when exposed to artificially generated free radicals under simulated solar irradiation and different experimental conditions (pH values and mineral concentrations in the thermal water) was researched. Three different dermocosmetic products designed with raw minerals and water from Kanjiža Spa were tested. Our findings confirmed the protective effect of mineral water, as evidenced by the higher stability of vitamin C in thermal water. The degradation of vitamin C was significantly reduced in the presence of mineral water, with the least degradation occurring at pH = 7, which closely matches human skin pH. These results were further validated using 2,2-diphenyl-1-picrylhydrazyl and ABTS tests. Overall, the obtained results underscore the therapeutic and commercial potential of Kanjiža Spa’s mineral water, suggesting that it could be a valuable ingredient in next-generation skincare and pharmaceutical products. Full article

A highly sensitive, selective and recyclable histidine detection method based on magnetic Fe₃O₄@mTiO₂ (M-TiO₂) nanocomposites with SERRS was developed. Mesoporous M-TiO₂ nanoparticles were functionalized with 4-aminothiophenol and then coupled with histidine through an azo coupling reaction in 5 min, producing the corresponding azo compound. The strong and specific SERRS response of the azo product allowed for ultrasensitive and selective detection for histidine with an M-TiO₂ device loaded with Ag NPs due to the molecular resonance effect and plasmonic effect of Ag NPs under a 532 nm excitation laser. The sensitivity was further enhanced with the magnetic enrichment of M-TiO₂. The limit of detection (LOD) was as low as 8.00 × 10⁻¹² mol/L. The M-TiO₂ demonstrated applicability towards histidine determination in human urine without any sample pretreatment. Additionally, the M-TiO₂ device can be recycled for 3 cycles with the photodegradation of the azo product under UV irradiation due to TiO₂-assisted and plasmon-enhanced photocatalysis. In summary, a multifunctional and recyclable M-TiO₂ device was synthesized based on azo coupling and SERRS spectroscopy for ultra-sensitive and specific histidine sensing. In addition, the proposed system demonstrated the potential for the multiplex determination of toxic compounds in the fields of food safety, industrial production and environmental protection, which benefit from the fingerprint property and universality of SERRS. Full article

The photodegradation of azithromycin present was carried out in water using H₂O₂ under UV irradiation. The reaction variables considered in this study were the amount of H₂O₂ solution and the initial concentration of azithromycin to evaluate the performance of the photodegradation process. The azithromycin degradation was not observed in the dark during stirring for 20 min. The study showed an efficient photodegradation of azithromycin using H₂O₂ as an oxidant in the presence of UV irradiation. The azithromycin degradation was altered significantly by the pH of the irradiated solution. The degradation was low at an acidic pH and showed an increasing trend as the pH changed to basic. The azithromycin degradation increased with a higher amount (higher concentration) of H₂O₂. The degradation of azithromycin decreased with a higher concentration of azithromycin in the reacting solution. The highest degradation of AZT was achieved in 1 h using a 1.0 ppm AZT solution containing 3 mL of H₂O₂. The experimental data obtained were well-fitted to zero-order reaction kinetics. The results of this study were found quite excellent. They showed 100% degradation in 1 h when compared with those reported in the literature, both with photocatalysis using nanomaterials and photolysis using light irradiation and/or H₂O₂. The UV/H₂O₂ system was found to be quite efficient for the photodegradation of azithromycin, and this system can be applied to degrade other organic pollutants present in industrial wastewater. Full article

Polyurethane/silk protein–bismuth halide oxide composite films were fabricated using a blending-wet phase transformationin situsynthesis method. The crystal structure, micromorphology, and optical properties were conducted using XRD, SEM, and UV-Vis DRS characterize techniques. The results indicated that loaded silk protein enhanced the hydrophilicity and pore structure of the polyurethane composite films. The active species BiOX were observed to grow as nanosheets with high dispersion on the internal skeleton and silk protein surface of the polyurethane–silk protein film. The photocatalytic efficiency of BiOX/PU-SF composite films was assessed through the degradation of Rhodamine B under visible light irradiation. Among the tested films, the BiOBr/PU-SF composite exhibited the highest removal rate of RhB at 98.9%, surpassing the removal rates of 93.7% for the BiOCl/PU-SF composite and 85.6% for the BiOI/PU-SF composite. Furthermore, an active species capture test indicated that superoxide radical (•O₂⁻) and hole (h⁺) species played a predominant role in the photodegradation process. Full article

Alectinib HCl (ALBHCl) is a tyrosine kinase inhibitor used for non-small cell lung carcinoma (NSCLC). The aim of this study is to unlock some of the physicochemical properties of ALBHCL that serve as a database for any future studies. A solubility study of ALBHCL was performed in different solvents. Also, photostability was tested in the solution and solid states, and the order of reaction and rate constant were calculated. In addition to the pH solubility relation, the pH-rate relation at different temperatures was also studied, and the profiles were constructed. A solubility study was also performed in different media for the purpose of optimizing suitable sink conditions for the in vitro dissolution testing of solid dosage forms. Solubility tests in multiple solvents and pH conditions revealed that the highest solubility was in DMSO, methanol, and chloroform, with acidic media yielding the maximum solubility but degrading at rather low pH levels. ALBHCL proved unstable at high temperatures and under light exposure, with varying stability across different pH levels. The optimal dissolution media for in vitro oral dosage form evaluation were determined, achieving sink conditions at pH levels of 6.8 and 4.5 with specific additives. This study enhances the existing database on ALBHCL’s physicochemical properties, emphasizing the importance of pH optimization in pharmaceutical processes and providing valuable insights into its pharmaceutical application. Full article

The removal of pesticides and other organic pollutants from water through advanced oxidation processes (AOPs) holds great promise. The main advantage of these technologies is that they remove, or at least reduce, pesticide levels by mineralization rather than transfer, as in conventional processes. This study first evaluated the effectiveness of UV/S₂O₈⁼ compared to heterogeneous photocatalysis using UV/TiO₂ processes on the degradation of two commonly used herbicides (terbuthylazine and isoproturon) in aqueous solutions using a laboratory photoreactor. In addition, the effect of the UV wavelength on the degradation efficiency of both herbicides was investigated. Although the degradation rate was greater under UV(254)/S₂O₈⁼ nm than under UV(365)/S₂O₈⁼ nm, complete degradation of the herbicides (0.2 mg L⁻¹) was achieved within 30 min under UV-366 nm using a Na₂S₂O₈ dose of 250 mg L⁻¹ in the absence of inorganic anions. To assess the impact of the water matrix, the individual and combined effects of sulfate (SO₄⁼), bicarbonate (HCO₃⁻), and chloride (Cl⁻) were evaluated. These can react with hydroxyl (HO^•) and sulfate (SO₄^•−) radicals generated during AOPs to form new radicals with a lower redox potential. The results showed negligible effects of SO₄⁼, while the combination of HCO₃⁻ and Cl⁻ seemed to be the key to the decrease in herbicide removal efficiency found when working with complex matrices. Finally, the main intermediates detected during the photodegradation process are identified, and the likely pathways involving dealkylation, dechlorination, and hydroxylation are proposed and discussed. Full article

This study examines the use of SrAl₂O₄: Eu²⁺, Dy³⁺ long-afterglow materials doped into g-C₃N₄/TiO₂ coatings for photodegradation. The prepared sample was tested for the purification of automotive exhaust fumes, with the optimal mass ratio of g-C₃N₄/TiO₂ and SrAl₂O₄: Eu²⁺, Dy³⁺ determined to be 1:1. Characterization tests, including XRD, FT-IR, XPS, and TG-DSC, were conducted to evaluate the microstructure and properties of the samples. Under poor lighting conditions, g-C₃N₄/TiO₂ reduced CH and NO_x by 59 ppm and 13 ppm within 4 h, respectively, while g-C₃N₄/TiO₂/SrAl₂O₄: Eu²⁺, Dy³⁺ decreased CH and NO_x by 98ppm and 34ppm, respectively, resulting in a significant improvement in degradation efficiency. The addition of long-afterglow materials significantly improves the efficiency of photocatalysts in purifying exhaust fumes in low-light environments, providing potential value for all-weather exhaust treatment in the future. Full article

In this study, carbon-quantum-dot (CQD)-decorated TiO₂ was prepared using an ultrasonic doping method and applied in the photocatalytic degradation of naphthalene under sunlight irradiation. The CQDs were synthesized from a typical macroalgae via diluted sulfuric acid pretreatment and hydrothermal synthesis using an optimal design, i.e., 3 wt% and 200 °C, respectively. The CQD/TiO₂ composite remarkably enhanced the photocatalytic activity. The degradation of naphthalene under a visible light environment indicated that there is a synergistic mechanism between the CQDs and TiO₂, in which the generation of reactive oxygen species is significantly triggered; in addition, the N that originated from the macroalgae accelerated the photocatalytic efficiency. Kinetic analysis showed that the photocatalytic behavior of the CQD/TiO₂ composite followed a pseudo-first-order equation. Consequently, our combined experimental approach not only provides a facile pretreatment process for bio-CQDs synthesis, but also delivers a suitable TiO₂ photocatalyst for the visible environment along with critical insights into the development of harmful macroalgae resources. Full article

Microplastics (MPs) pose a profound environmental challenge, impacting ecosystems and human health through mechanisms such as bioaccumulation and ecosystem contamination. While traditional water treatment methods can partially remove microplastics, their limitations highlight the need for innovative green approaches like photodegradation to ensure more effective and sustainable removal. This review explores the potential of nanomaterial-enhanced photocatalysts in addressing this issue. Utilizing their unique properties like large surface area and tunable bandgap, nanomaterials significantly improve degradation efficiency. Different strategies for photocatalyst modification to improve photocatalytic performance are thoroughly summarized, with a particular emphasis on element doping and heterojunction construction. Furthermore, this review thoroughly summarizes the possible fundamental mechanisms driving the photodegradation of microplastics facilitated by nanomaterials, with a focus on processes like free radical formation and singlet oxygen oxidation. This review not only synthesizes critical findings from existing studies but also identifies gaps in the current research landscape, suggesting that further development of these photocatalytic techniques could lead to substantial advancements in environmental remediation practices. By delineating these novel approaches and their mechanisms, this work underscores the significant environmental implications and contributes to the ongoing development of sustainable solutions to mitigate microplastic pollution. Full article

Evaporative water concentration takes place in arid or semi-arid environments when stationary water bodies, such as lakes or ponds, prevalently lose water by evaporation, which prevails over outflow or seepage into aquifers. Absence or near-absence of precipitation and elevated temperatures are important prerequisites for the process, which has the potential to deeply affect the photochemical attenuation of pollutants, including contaminants of emerging concern (CECs). Here we show that water evaporation would enhance the phototransformation of many CECs, especially those undergoing degradation mainly through direct photolysis and triplet-sensitized reactions. In contrast, processes induced by hydroxyl and carbonate radicals would be inhibited. Our model results suggest that the photochemical impact of water evaporation might increase in the future in several regions of the world, with no continent likely being unaffected, due to the effects of local precipitation decrease combined with an increase in temperature that facilitates evaporation. Full article

The binary heterostructured semiconducting visible light photocatalyst of the iron-doped graphitic carbon nitride/bismuth molybdate (Fe-g-C₃N₄/Bi₂MoO₆) composite was prepared by coupling with Fe-doped g-C₃N₄ and Bi₂MoO₆ particles. In the present study, a comparison of structural characteristics, optical properties, and photocatalytic degradation efficiency and activity between Fe-doped g-C₃N₄ particles, Bi₂MoO₆ particles, and Fe-g-C₃N₄/Bi₂MoO₆ composite was investigated. The results of X-ray diffraction (XRD) examination indicate that the hydrothermal Bi₂MoO₆ particles have a single orthorhombic phase and Fourier transform infrared (FTIR) spectroscopy analysis confirms the formation of Fe-doped g-C₃N₄. The optical bandgaps of the Fe-doped g-C₃N₄ and Bi₂MoO₆ particles are 2.74 and 2.73 eV, respectively, as estimated from the Taut plots obtained from UV-Vis diffuse reflectance spectroscopy (DRS) spectra. This characteristic indicates that the two semiconductor materials are suitable for absorbing visible light. The transmission electron microscopy (TEM) micrograph reveals the formation of the heterojunction Fe-g-C₃N₄/Bi₂MoO₆ composite. The results of photocatalytic degradation revealed that the developed Fe-g-C₃N₄/Bi₂MoO₆ composite photocatalyst exhibited significantly better photodegradation performance than the other two single semiconductor photocatalysts. This property can be attributed to the heterostructured nanostructure, which could effectively prevent the recombination of photogenerated carriers (electron–hole pairs) and enhance photocatalytic activity. Furthermore, cycling test showed that the Fe-g-C₃N₄/Bi₂MoO₆ heterostructured photocatalyst exhibited good reproducibility and stability for organic dye photodegradation. Full article