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The rampant misuse of organic dyes has exacerbated environmental pollution to an alarming degree. SrBi 4 Ti 4 O 15 , a layered perovskite semiconductor material, demonstrates considerable potential in the degradation of organic dyes, and efforts have been made to enhance its photocatalytic efficiency. In this study, La3+ doping was utilized to synthesize SrBi 4-x La x Ti 4 O 15 (x = 0, 0.10, 0.15, 0.25, 0.40) nanosheet photocatalysts, and their photocatalytic performance and underlying mechanisms were comprehensively investigated. XRD and Raman spectroscopy revealed that La3+ doping replaced Bi3+ at the A-site, resulting in a reduction of the interlayer spacing of [TiO 6 ] octahedra. Combined with DFT calculations, La3+ doping was found to widen the band gap of SrBi 4 Ti 4 O 15 and raise the Fermi level. Additionally, La3+ doping significantly increased the ratio of the Ti 3d component at the bottom of the conduction band, favoring the migration of photogenerated electrons along the [TiO 6 ] octahedra and accelerating the separation of photogenerated carriers. SEM and BET analyses revealed that La3+ doping not only increased the size of the nanosheets but also significantly enhanced their specific surface area, thereby exposing more active sites. Degradation experiments of Rhodamine B (Rh B) under UV light demonstrated that the photocatalytic efficiency of SrBi 3.75 La 0.25 Ti 4 O 15 (k = 0.0514 min-1) was 2.66 times higher than that of the original SrBi 4 Ti 4 O 15 (k = 0.0193 min-1). The theoretical degradation pathway of Rh B was elucidated using LC-MS analysis and the developmental toxicity of potential intermediates was analyzed. Moreover, the SrBi 3.75 La 0.25 Ti 4 O 15 photocatalyst also exhibited excellent degradation efficacy against Methylene Blue (MB), Crystal Violet (CV), and Methyl Orange (MO). This study provides both theoretical and experimental insights into improving the photocatalytic performance of SrBi 4 Ti 4 O 15 , thereby enhancing its potential for industrial application. [Display omitted] [ABSTRACT FROM AUTHOR]

The present work highlights the synthesis of graphene oxide (GO) modified polythiophene (PTh) for its application as an antibacterial agent as well as a visible light active photocatalyst. PTh was synthesized via the interfacial polymerization method using FeCl3 as initiator and then formulated as nanohybrids by mixing it in different weight ratios with graphene oxide (GO) i.e., 1 wt.%,3 wt.% and 5 wt. %. PTh and GO/PTh nanohybrids were characterized using FTIR, UV-visible, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) techniques. The polymerization of PTh as well as modification of PTh with GO was confirmed by IR studies, while the shifting of electronic transitions of PTH upon modification with GO were confirmed by the UV-visible studies. The degradation of dyes, Alizarin Yellow (AY), Basic Blue (BB) and Congo Red (CR) was carried out via sonophotocatalysis under visible light using PTh and GO/PTh as catalysts for a period of 60 min. The GO/PTh revealed higher degradation efficiency as compared to PTh. To evaluate its effectiveness as an antibacterial agent against Bacillus subtilis, disk diffusion inhibitory assay was carried out under dark and light conditions. The results showed that PTh and GO/PTh nanohybrids had bactericidal properties, regardless of light exposure. The results of the minimal inhibitory concentration (MIC) assay indicated the nanohybrid of 3-GO/PTh had the lowest MIC, followed by 1-GO/PTh and 5-GO/PTh. [ABSTRACT FROM AUTHOR]

[Display omitted] • Combining tetragonal BTO nanoparticles and 2D MXene nanosheets creates BTO-MX, which can degrade 90 % of RhB in 15 min. • MXene nanosheets enhance electrical conductivity and energy conversion rate during advanced oxidation process. • The heterogeneous structure of BTO-MX provides sufficient active sites, aiding in the adsorption and degradation of RhB. • The synergistically piezo-photocatalytic properties enabled by efficient carrier generation and separation in BTO-MX. Piezo-photocatalysis combines photocatalysis and piezoelectric effects to enhance catalytic efficiency by creating an internal electric field in the photocatalyst, improving carrier separation and overall performance. This study presents a high-performance piezo-photocatalyst for efficient dye degradation using a synergistic barium titanate (BTO)-MXene composite. The composite was synthesized via a facile method, combining the unique properties of BTO nanoparticles with the high conductivity of MXene. The structural and morphological analysis confirmed the successful formation of the composite, with well-dispersed BTO nanoparticles on the MXene surface. The piezo-photocatalytic activity of the composite was evaluated using a typical dye solution (Rhodamine B: RhB) under ultraviolet irradiation and mechanical agitation. The results revealed a remarkable enhancement in dye degradation (90 % in 15 min for piezo-photocatalysis) compared to individual stimuli (58.2 % for photocatalysis and 95.8 % in 90 min for piezocatalysis), highlighting the synergistic effects between BTO and MXene. The enhanced catalytic performance was attributed to the efficient charge separation and transfer facilitated by the composite's structure, leading to increased reactive species generation and dye molecule degradation. Furthermore, the composite exhibited excellent stability and reusability, showcasing its potential for practical applications in wastewater treatment. Overall, this work represents a promising strategy for designing high-performance synergistic catalysts, addressing the pressing need for sustainable solutions in environmental remediation. [ABSTRACT FROM AUTHOR]

ABSTRACT The existence of organic pollutants in aqueous media has become a vital issue and a critical threat to human health, where organic toxic dyes represent the major contaminants in wastewater. Over the past few years, photocatalytic techniques have garnered a lot of interest in dye removal from wastewater. In this study, a series of ErxTbxZn1 − 2xO nanophotocatalysts (where x = 0.00, 0.01, 0.03, and 0.05) were synthesized and coded as ZET0, ZET1, ZET2, and ZET3 NPs (nanoparticles). The chemical and physical characteristics of the NPs were investigated using Fourier‐transform infrared spectroscopy (FT‐IR), X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), energy‐dispersive X‐ray (EDX) spectroscopy, and ultraviolet–visible diffuse reflectance spectroscopy (UV–vis DRS) techniques. Further examination by performing photocatalytic experiments, ZET1 NPs demonstrated effective Rhodamine B (RhB) dye degradation within 60 min. It was found that the kinetic rate constant values were 0.008, 0.097, 0.050, and 0.040 min−1 for ZET0, ZET1, ZET2, and ZET3 NPs, respectively. Aside from their remarkable photocatalytic degradation efficiency, these ZET1 photocatalysts are highly stable even after five consecutive cycles. In addition, the active species test revealed that the primary oxidation species involved in the photocatalytic process are holes (h+) and hydroxyl radicals (•OH), and a possible photocatalytic mechanism for degrading RhB by ZET1 photocatalysts was tentatively proposed. The enhancement of the photocatalytic degradation efficiency is due to the low recombination rate of photogenerated charge carriers, as well as a strong synergistic impact of Tb, Er, and ZnO components. Thus, the current study could offer a versatile strategy for the design of new and effective nano photocatalysts for wastewater purification in the future. [ABSTRACT FROM AUTHOR]

Efficient photocatalysts play an important role in the various fields such as pollutant treatment and the generation of clean energy. Therefore, developing a photocatalyst with high activity is of great significance. Herein, scandium‐based fluorescent microspheres (Sc‐FMs) are facilely prepared through the one‐pot hydrothermal polymerization of scandium ions and tartaric acid. The prepared Sc‐FMs show strong blue solid‐state fluorescence, with a maximum emission at 412 nm. Meanwhile, Sc‐FMs possess a strong white‐light photocatalysis ability, which can be used for the photodegradation of dye pollutants (rhodamine 6 G) under low power white light without the assistance of any radical generating agents. In addition, the Sc‐FMs display good stability and recyclability. As a result, this new and efficient Sc‐FMs photocatalysts hold a promise for potential applications in environmental treatment. [ABSTRACT FROM AUTHOR]

This review explores advancements, challenges, and considerations in photocatalytic dye degradation for sustainable wastewater treatment. It highlights smart photocatalyst design, visible‐light‐responsive materials, and co‐catalyst engineering, which enhance system efficacy. Despite environmental concerns, the eco‐friendly aspects of photocatalysis offer a promising alternative to traditional methods. Future perspectives emphasize nanotechnology's role in developing effective photocatalysts and integrating visible‐light and solar‐driven systems to meet sustainability goals. Efforts in co‐catalyst engineering and reactor design aim to optimize processes, addressing kinetic and scalability challenges, while economic research focuses on reducing costs to improve competitiveness. [ABSTRACT FROM AUTHOR]

A palladium (Pd)-doped rGO/ZnO nanocomposite was prepared using the hydrothermal method. The nanocomposite underwent various analytical assessments to determine its structural, optical, and morphological properties. The analytical results confirmed the successful formation of the Pd-doped rGO/ZnO composite. This composite, referred to as Pd-rGO/ZnO, was employed for the photocatalytic degradation of Coomassie Brilliant Blue R-250 (CBR) dye. The prepared photocatalyst, Pd-rGO/ZnO, exhibited a remarkable 93% efficiency in degrading CBR dye within 150 min under UV light. The enhanced photocatalytic and antibacterial activities were achieved by modifying rGO and introducing Pd, which effectively increased the reactive surface area and facilitated electron transfer. Moreover, the composite also displayed significant antibacterial activity in a dose-dependent manner. Dye degradation over Pd-rGO/ZnO photocatalyst under UV light irradiation (DM – Dye molecules). [ABSTRACT FROM AUTHOR]

The sustainable and effective nanomaterials for photocatalyst are greatly enviable to protect water bodies from organic waste. In this regard, nanocomposite of NiO-PdO-Pd was prepared via sol gel route using organic pattern and scrutinized catalytic agent for remediation of methyl orange (MO) in water. Verification of phase formation in obtained product was done utilizing X-ray diffraction, energy-dispersive spectroscopic analysis, along with Raman spectroscopy while the nano-structures were explored using FE-scanning electron microscopy. Existence of organic functional groups (OFGs) in the obtained product was revealed using Fourier-transform-infrared spectroscopy along with gas-chromatography-mass spectrometry. Functionalized nanocomposite (FN) was studied for degradation of MO both under solar light and under dark environment. Organic compound incorporated NiO-PdO-Pd has demonstrated outstanding catalytic behavior with 96% and 76% degradation of MO under light as well as under dark, within 15 min. Additionally, catalyst has proved to be having excellent stability with pseudo-first-order kinetics under light (R2 = 0.86) and under dark conditions (R2 = 0.94). [ABSTRACT FROM AUTHOR]

A layered Na2SnO3 with honeycomb structure was synthesized by solid state route using sodium carbonate and tin oxide. The prepared sample was characterized by different physicochemical characterization techniques like X‐ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X‐ray spectroscopy (EDS), X‐ray photoelectron spectroscopy (XPS), ultraviolet visible spectroscopy (UV–vis), photoluminescence spectra (PL), N2 adsorption technique (Brunauer–Emmett–Teller, electrochemical impedance spectroscopy (EIS). The photodegradation of rose bengal dye under UV light was studied. Due to honeycomb structure and high surface area of Na2SnO3, the complete degradation of rose Bengal was observed in 90 min under UV light irradiation. Results of photocatalytic dye degradation reaction demonstrated that Na2SnO3 can be employed as photocatalyst under UV light irradiation. [ABSTRACT FROM AUTHOR]

Micro and nanomechanical devices offer enhanced sensing capabilities for detecting biological and chemical small molecules. However, miniaturization necessitates advanced fabrication processes and complex measurement systems, hindering routine sensor analysis. While alternative methods like 3D printing show promise, challenges such as low device resolution persist due to intrinsic damping of polymer inks. In this study, an array of micrometric pillar resonators is fabricated in Ti6Al4 V alloy using additive manufacturing based on laser powder bed fusion technology. These metallic nanomechanical resonators exhibit a very high quality factor with minimal difference between air and vacuum measurements due to low intrinsic damping. Furthermore, titania nanotubes grown on the pillars via anodic oxidation heighten sensitivity for molecular dye degradation evaluation. Leveraging the weak coupling phenomenon among the pillars in the array, these devices facilitate large‐scale parallelized measurements, here demonstrated with real‐time analysis of dye degradation process. This approach to creating mass sensing devices via metallic additive manufacturing can usher in a new generation of highly performing resonating sensor arrays, offering a cost‐effective and efficient alternative to traditional silicon microfabrication methods. [ABSTRACT FROM AUTHOR]

Zinc sulfide/molybdenum disulfide (ZnS@MoS 2) nanorods composites were synthesized by straightforward hydrothermal method. Experimental investigations revealed that the kinetic coefficient (k) of ZnS@MoS 2 was 0.0667 min−1 within 30 min, with a degradation efficiency of 88.6 % toward methylene blue dye in presence of both stirring and light. These performances were notably higher compared to conditions with either light or stirring irradiation alone. Moreover, ZnS@MoS 2 composites not only had excellent catalytic activity but also good cyclic stability. The catalytic mechanism of ZnS@MoS 2 for degradation of MB organic pollutant was further discussed based on relevant characterization. Under both stirring and light conditions, the strong piezoelectric field effectively promoted charge carriers separation and reduced the electron-hole recombination rate, thus enhancing catalytic degradation efficiency for ZnS@MoS 2. This research holds significant importance for the development of high-performance catalysts in wastewater treatments field. [Display omitted] • A novel ZnS@MoS 2 nanorods composites catalyst was rationally designed. • ZnS@MoS 2 exhibited superior catalytic activity and stability toward degradation of methylene blue dye. • Excellent catalytic performance was mainly ascribed to the efficient charge carriers separation. • A possible catalytic mechanism of ZnS@MoS 2 was clarified. [ABSTRACT FROM AUTHOR]

The field of environmental and water remediation faces a significant challenge in removing organic dyes from wastewater, particularly Rhodamine B (RhB), a stubborn dye used in various industries. Traditional treatment methods struggle with its resistance to decomposition, posing risks to water quality, human health, and aquatic life. This study demonstrates a novel approach to enhance photocatalytic efficiency for RhB degradation by constructing a MOF-5/g-C3N4 composite through a facile mechanical grinding method, which is unprecedented. The composite addresses the limitations of g-C3N4, such as rapid recombination of electron–hole pairs, low electron transfer rates, and small surface area, by forming a heterojunction with MOF-5. The composite exhibits enhanced photocatalytic efficiency for the degradation of RhB under sunlight, with a degradation of 91.5% achieved within 90 min. Optimization studies highlight the importance of pH and catalyst dosage in the degradation process. The reusability test shows consistent performance over five successive cycles, maintaining a degradation efficiency of over 90%. Total organic carbon (TOC) analyses confirm the mineralization of the dye solution to 82.05% after 90 min of irradiation, demonstrating the environmental benignity of the composite. Trapping experiments suggest the involvement of superoxide radicals, electrons, and holes in the photocatalytic mechanism. This study introduces a promising strategy for addressing challenges in dye degradation through innovative composite materials. [ABSTRACT FROM AUTHOR]

Amongst the many types of food waste, eggshells contain various minerals and bioactive materials, and they can become hazardous if not properly disposed of. However, they can be made useful for the environment and people by being converted to environmentally friendly catalytic materials or environmental purification agents. Simple calcination can enhance their properties and thereby render them suitable for catalytic and environmental applications. This work aimed to prepare CaO from waste eggshells and examine its effectiveness in photocatalytic pollution remediation, electrocatalytic activity, optical sensing, and antibacterial activities. As opposed to other techniques, this calcination process does not require any chemical reagents due to the high purity of CaCO3 in eggshells. Calcium oxide nanoparticles were prepared by subjecting waste eggshells (ES) to high-temperature calcination, and the synthesized CaO nanoparticles were characterized for their structural, morphological, chemical, optical, and other properties. Furthermore, their photocatalytic degradation of methylene blue dye and antibacterial efficiency against Escherichia coli and Staphylococcus aureus were investigated. It was found that the green-converted CaO can be efficiently used in environmental applications, showing good catalytic properties. [ABSTRACT FROM AUTHOR]

The one‐step green synthesis of wide band gap zinc oxide@zinc sulfide (ZnO@ZnS) core–shell nanostructures offers promising prospects in wastewater treatment. These nanostructures exhibit a porous nature crucial for effective dye adsorption, as evidenced by Brunauer‐Emmett‐Teller (BET) and microscopic characterization. The synthesized material demonstrates high stability and minimal agglomeration, verified through BET analysis and zeta potential measurements. X‐ray powder diffraction confirms the presence of ZnO and ZnS phases. Transmission electron microscopy reveals the development of porous nanorods on the core surface, maximizing the surface area for dye adsorption. In wastewater treatment, the nanostructures exhibit notable performance, degrading 90% of malachite green and 50% of rhodamine B dyes within 120 min under normal conditions. Detailed discussions delve into the degradation mechanism, elucidating the major species responsible for the process. This study underscores the potential of ZnO@ZnS nanostructures in efficient organic pollutant removal, marking a significant advancement in environmental remediation. [ABSTRACT FROM AUTHOR]

Taraxacum mongolicum, also known as "Dandelion", distributes widely and is a famous medicinal plant with the functions of clearing heat-toxin and detumescence. In this study, we utilized the easily available T. mongolicum extract as both green reducing and capping agents for synthesizing copper oxide nanoparticles (CuO NPs), and the reaction took place in only one step and there was no need for an external chemical reducing reagents, which consequently enable the reaction process be simple, rapid, nontoxic, cost-effective, and eco-friendly. The obtained CuO NPs possess monoclinic crystal structure with high crystallinity, exhibit rough and irregular surface topography, and are close to spherical in shape with a particle size of ∼30-50 nm. Degradation experiments demonstrated that the CuO NPs display excellent catalytic efficacy towards rhodamine-B (Rh-B) and malachite green (MG) dyes under both dark and light irradiation conditions, in particular for degrading MG, with the degradation efficiency after H2O2-assisted treatment reaching up to 93.81% under light irradiation within 210 min, and the degradation mechanism is relevant to the photo-assisted heterogeneous Fenton-like catalytic reaction. On this basis, the degradation kinetics of the CuO NPs on two selected dyes were also investigated. The cycling test indicated the good stability and reusability of the CuO NPs for dye degradation. Furthermore, the antibacterial properties of the CuO NPs were also examined. The results revealed that these nanoparticles are well capable of inhibiting the activity of Staphylococcus aureus and Escherichia coli, especially against Gram-positive bacteria, with the minimum inhibitory concentration (MIC) value of 400 μg/ml. Overall, these findings suggest the green synthesized CuO NPs could be promising for use in the decontamination of dyes wastewater or employed in medical devices for the prevention or treatment of bacterial infections. [ABSTRACT FROM AUTHOR]

This study presents barium sulfate nanoparticles (BaSO4 NPs) synthesis and characterization using leaf extract from Antigonon leptopus Hook. & Arn. Various analytical techniques such as X‐ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X‐ray (EDX), and Fourier transform infra‐red spectroscopy (FTIR) were employed to confirm the structural properties, crystallinity, surface morphology, chemical purity, and presence of organic compounds. The XRD analysis indicated the crystallinity of BaSO4 NPs with an average crystallite size of 7.8 nm, whereas SEM imaging revealed round morphology and EDX confirmed good chemical purity. FTIR spectroscopy provided evidence of both BaSO4 NPs and organic compounds from the leaf extract. The synthesized BaSO4 NP was then applied to degrade four different azo and azonium dyes, demonstrating effectiveness under various conditions. Furthermore, the impact of BaSO4 NP on the germination and growth of foxtail millet (Setaria italica (L.) P.Beauv.) was investigated. Preliminary findings suggested that BaSO4 NPs promoted seed germination and growth of foxtail millet at low concentrations. However, caution is advised as higher concentrations may have a toxic effect. Overall, this study highlights the potential of bio‐forged BaSO4 NPs for environmental remediation (dye degradation) and agricultural applications (enhancement of seed germination and growth) while emphasizing the importance of dosage control due to potential toxicity at higher concentrations. [ABSTRACT FROM AUTHOR]

Synthesis of silver nanoparticles (Ag NPs) using microalgae is gaining recognition for its environmentally friendly and cost-effective nature while maintaining high activity of NPs. In the present study, Ag NPs were synthesized using a methanolic extract of Chlorella vulgaris and subjected to calcination. The X-ray diffraction (XRD) analysis showed a crystalline nature of the products with Ag2O and Ag phases with an average crystalline size of 16.07 nm before calcination and an Ag phase with 24.61 nm crystalline size after calcination. Fourier transform infrared spectroscopy (FTIR) revealed the capping functional groups on Ag NPs, while scanning electron microscopy (SEM) displayed their irregular morphology and agglomeration after calcination. The organic coating was examined by energy-dispersive X-ray spectroscopy (EDX) and thermogravimetric (TGA) analyses, confirming the involvement of the metabolites. The UV–Vis analysis showed a difference in optical properties due to calcination. Synthesized Ag NPs were applied for the photodegradation of hazardous dye Brilliant Blue R in visible light. Different values of light intensity, catalyst dose, initial dye concentration, and pH were tested to identify the optimal set of operating conditions. The highest degradation efficiency of 90.6% with an apparent rate constant of 0.04402 min−1 was achieved after 90 min of irradiation in the highest tested catalyst dosage. [ABSTRACT FROM AUTHOR]

Piezocatalysis‐induced dye degradation has garnered significant attention as an effective method for addressing wastewater treatment challenges. In our study, we employed a room‐temperature sonochemical method to synthesize piezoelectric barium titanate nanoparticles (BaTiO3: BTO) with varying levels of Li doping. This approach not only streamlined the sample preparation process but also significantly reduced the overall time required for synthesis, making it a highly efficient and practical method. One of the key findings was the exceptional performance of the Li‐doped BTO nanoparticles. With 20 mg of Li additive, we achieved 90 % removal of Rhodamine B (RhB) dye within a relatively short timeframe of 150 minutes, all while subjecting the sample to ultrasonic vibration. This rapid and efficient dye degradation was further evidenced by the calculated kinetic rate constant, which indicated seven times faster degradation rate compared to pure BTO. The enhanced piezoelectric performance observed in the Li‐doped BTO nanoparticles can be attributed to the strategic substitution of Li atoms, which facilitated a more efficient transfer of charge charges at the interface. Overall, our study underscores the potential of piezocatalysis coupled with advanced materials like Li‐doped BTO nanoparticles as a viable and promising solution for wastewater treatment, offering both efficiency and environmental sustainability. [ABSTRACT FROM AUTHOR]

The primary aim of this study is to investigate the degradation efficacy of the Ppy/TiO2-Fe photocatalyst for MB dye in an aqueous solution. Firstly, the direct addition of TiO2 and Fe was done to prepare Ppy/TiO2-Fe photocatalyst. Fourier transformation infrared spectroscopy, XRD, SEM, BET surface area analysis, and magnetization tests established the formation of the Ppy/TiO2-Fe photocatalyst. The crystallite sizes of TiO2, Fe-TiO2, and Ppy/TiO2-Fe photocatalyst were estimated to be 24.99 nm, 21.94 nm, and 21.84 nm, respectively. For the synthesis confirmation, the FTIR spectrum confirmed the existence of Ti-O, Fe-O, and Ppy-related bonds. While comparing the SEM images, the impact of polypyrrole on the particle shape was observed with less aggregation and increased surface roughness. The VSM analysis revealed that incorporating polypyrrole (Ppy) into Fe-TiO2 significantly enhances its magnetic properties, with Ppy/TiO2-Fe exhibiting superparamagnetic behavior, characterized by a higher saturation magnetization (Ms) of 33.11 emu/g and a lower coercivity (Hc) of 0.160 Oe, compared to Fe-TiO2's Ms of 1.09 emu/g and Hc of 341.39 Oe. The N2 sorption desorption, with a specific surface area of 2.25 × 102 m2/g, is beneficial for photocatalytic activity. The concentration of dye, amount of catalyst, pH, and temperature were studied to evaluate the photocatalytic efficiency of the synthesized Ppy/TiO2-Fe photocatalyst under different conditions. The findings revealed a degradation efficiency of 91.92%. The degradation rate reached 91.92% under optimal conditions within 120 min and could be fitted well by first-order kinetics. The photocatalytic efficiency was also evaluated for the scavenger, and the concentration of H2O2 and the reusability of the catalyst were demonstrated. Based on the observed results, the Ppy/TiO2-Fe photocatalyst could be applied more effectively and efficiently to photocatalytic degradation of organic dyes in wastewater treatment. [ABSTRACT FROM AUTHOR]

Water effluents are excessively contaminated by organic dyes, causing significant damage to the flora and fauna. In this research, photocatalysis was used for the removal of three organic dyes, methylene blue (MB), methyl orange (MO), and rhodamine B (RhB). ZnO nanoparticles biosynthesized through an eco-friendly route were used as photocatalysts, employing extracts of Turnera diffusa as the reducing agent of the metallic precursor in these nanoparticle syntheses. The nanoparticles were characterized to know their structure by Attenuated Total Reflectance Spectroscopy (ATR-IR), X-ray Diffraction (XRD), and X-ray Emitted Photoelectron Spectroscopy (XPS). Thermogravimetric Analysis (TGA) was used to evaluate the thermal behavior, the BET method was used to evaluate the specific surface area, the morphology was analyzed by Transmission Electron Microscopy (TEM), and finally, the TAUC model was used to obtain the energy gap by UltraViolet-Visible spectroscopy (UV-Vis) spectra. The photocatalytic activity results presented a 100% degradation in 180 and 50 min for MB and MO dyes, respectively. And a 77% degradation for RhB at 180 min. This indicates that the biosynthesized NPs are adequate for removing contaminants found in water. [ABSTRACT FROM AUTHOR]

Nanotechnology has enormous, economic, social, and environmental ramifications. Due to their capacity to survive in complex processes, inorganic nanomaterials like metal/metal oxides have received substantial study during the past decade. Nanoparticles have antibacterial, magnetic, electrical, and catalytic characteristics due to their greater surface area. There are several methods to develop nanoparticles but environment friendly behavior with no toxic byproducts attracts researchers toward biological process of nanoparticles. This work synthesizes copper oxide (CuO) nanoparticles and zinc oxide (ZnO) with Aloebarbadensis (Aloe vera) leaves extract and successfully characterizes them with different analytical techniques. The catalytic activity of such nanoparticles tests over different cationic and anionic dyes like methylene blue (MB), methyl orange (MO), and methyl red (MR) for different intervals of time and reveals. The degradation efficiency of CuO nanoparticles for MB, MO, and MR dyes are 59.92%, 73.48%, and 73.10% respectively, and for ZnO nanoparticles it is 81.44%, 76.46%, and 63.30% for MB, MO, and MR dyes respectively under the exposure of sunlight for 8 h. The present work successfully develops an ecofriendly process of dye degradation by biologically synthesized nanoparticles. [ABSTRACT FROM AUTHOR]

Dyes are the coloured substances that are applied on different substrates such as textiles, leather and paper products, etc. Azo dyes release from the industries are toxic and recalcitrant wastewater pollutants, therefore it is necessary to degrade these pollutants from water. In this study, the palladium (0) nanoparticles (PdNPs) were generated through the biological process and exhibited for the catalytic degradation of azo dye. The palladium nanoparticles (PdNPs) were synthesized by using the cell-free approach i.e. extract of fungal strain Rhizopus sp. (SG-01), which significantly degrade the azo dye (methyl orange). The amount of catalyst was optimized by varying the concentration of PdNPs (1 mg/mL to 4 mg/mL) for 10 mL of 50 ppm methyl orange (MO) dye separately. The time dependent study demonstrates the biogenic PdNPs could effectively degrade the methyl orange dye up to 98.7% with minimum concentration (3 mg/mL) of PdNPs within 24 h of reaction. The long-term stability and effective catalytic potential up to five repeated cycles of biogenic PdNPs have good significance for acceleration the degradation of azo dyes. Thus, the use of biogenic palladium nanoparticles for dye degradation as outlined in the present study can provide an alternative and economical method for the synthesis of PdNPs as well as degradation of azo dyes present in wastewater and is helpful to efficiently remediate textile effluent. [ABSTRACT FROM AUTHOR]

Plasma-based methods present a highly efficient approach for reclaiming valuable metals and nanoparticles from discarded metal scraps and minerals. In this research, we employed the thermal plasma arc discharge (TPAD) method to synthesize mixed-phase spinal-type magnesium aluminate and magnesium oxide (MgAl 2 O 4 /MgO) nanocomposites ranging in size from 10 to 120 nm, using discarded MgAl alloy waste scraps as the primary material. By employing comprehensive characterization techniques such as powder X-ray diffraction (XRD), transmission electron microscopy (TEM), and energy dispersive X-ray analysis (EDS), we successfully confirmed the formation of highly crystalline MgAl 2 O 4 /MgO nanocomposites, showcasing a nearly spherical morphology. The surface area of the prepared nanocomposites was investigated using Brunauer-Emmett-Teller (BET) analysis; the values are 51.3 m2g-1. The synthesized MgAl 2 O 4 /MgO nanocomposites displayed exceptional photocatalytic activity toward industrial wastewater and commercial dye. Moreover, investigated the storage properties of MgAl 2 O 4 /MgO nanocomposites as an electrode material, revealing a good specific capacitance of 379.2 F/g at a current density of 1 A/g, demonstrating pseudocapacitive behavior. These results offer valuable insights into sustainable waste utilization and the development of high-performance nanomaterials for practical applications in various fields. [ABSTRACT FROM AUTHOR]

In this work, efficient catalyst is prepared using ZnO and α -Fe2O3 along with a surface modification using 2-methylimidazole. Surface modified feature of the catalyst is confirmed by the shifting of vibrational frequency to higher wavenumber. Photocatalytic properties of the as-synthesized and surface modified composites are investigated by measuring the degradation of Methylene Blue (cationic) dye under sunlight irradiation. Both the samples exhibited a similar photocatalytic efficiency of 78% under 300 min. The effect of surface modification shows no significant enhancement on the cationic dye removal. Further, the samples are tested for the degradation of Methyl Blue (anionic) dye in dark condition to validate the effect of functionalization. Surface functionalized sample exhibits 96% efficiency compared to 86% for the pristine sample. Thus, surface modification has extended to be one of the promising techniques for enhancing the catalytic properties of composites. [ABSTRACT FROM AUTHOR]

The advanced oxidation process involves photocatalytic degradation, which is a propitious method of treating wastewater. However, to augment the photocatalytic activity of photocatalysts, the surface plasmon resonance (SPR) method is a highly promising candidate. Herein, we prepared bismuth (Bi) and tungsten (W)-based metal oxide (Bi2WO6) coupled with Ag as a semiconducting metal oxide-based plasmon resonance photocatalyst. Despite the SPR effect, the aggregation of particles lowers the efficiency of degradation. To get the better of it, morphology tuning agents and visible light-absorbing agents like CTAB (cetyltrimethylammonium bromide) were used. The prepared composite materials were characterized using sophisticated analytical instruments. The prepared materials were tested for their catalytic activity against Victoria Blue (VB) and Auramine O (AO) dyes. The composite material showed superior catalytic activity over the individual material, 97% and 98% for VB and AO, respectively. In addition, the toxicity of the byproducts (mutagenic toxicity, lethal concentration 50 (LC-50), and lethal dose (LD-50)) was estimated, and the detailed DFT interpretations were studied. Finally, a real-time agricultural application using post-treated water was conducted at the Epipremnum aureum plant. [ABSTRACT FROM AUTHOR]

The removal capabilities of organic pollutants methylene blue (MB) and textile dyes, especially the vat dyes from wastewater were reported using polyaniline (PANI), polypyrrole (PPy) and polythiophene (PTh) under direct sunlight irradiation. The comparative removal competence of these polymers is reported in the present work. Among the three polymers, PANI demonstrated nanofiber morphology, PPy showed a spherical-shaped structure, and the agglomerated and irregular morphology for the PTh was appreciated, and investigated by field-emission scanning electron microscopy (FESEM). However, the diameter of the particles remains 20–200 nm for these three polymers. The experimental findings for the photocatalytic performances of all three polymers demonstrated that PANI showed 97 % removal of MB in 660 min whereas, PPy and PTh showed 96  and 94 % removal, respectively. The results for removing vat dyes are 41 % for PANI, 44 % for PPy, and 45 % for PTh. Thus, PANI, PPy, and PTh are able to remove both MB and vat dyes, however the % of vat dyes removal is lower compared to MB. These outcomes may provide a new perception of conducting polymers as photocatalysts for organic dye removal in water purifications. [ABSTRACT FROM AUTHOR]

Heavy metals, pharmaceuticals, microplastics, dyes, and radionuclides in wastewater increasingly threaten environmental sustainability. Metal‐organic frameworks (MOFs) are versatile materials for mitigating these contaminants through efficient detection, capture, adsorption, and degradation. These crystalline structures, formed by combining metal ions with organic ligands, offer high surface area, tailored porosity, reproducibility, and robust chemical stability. This review compiles recent advancements in MOFs for pollutant removal, highlighting innovations in selective adsorption mechanisms for heavy metals, functionalized MOFs for pharmaceutical and microplastic removal, and enhanced photocatalytic degradation for dyes. Unique to this review is the integration of recent innovations such as ion exchange capabilities and photocatalytic degradation under visible light, addressing advanced applications that significantly enhance pollutant removal efficiency that other reviews have not covered comprehensively. The review also cites our group's recent work on a curcumin‐immobilized zeolitic imidazolate framework‐8 (Cmim@ZIF‐8) nanoprobe, demonstrating high selectivity for Fe2+ ions in water (detection limit: 7.64 μM) and its applicability in live‐cell imaging of HepG2 cells. Advanced techniques like density functional theory (DFT) simulations are employed to elucidate adsorption and degradation mechanisms, bridging theoretical insights with experimental findings. By critically evaluating these developments, the review identifies promising avenues for optimizing MOF design and advancing effective water treatment solutions. [ABSTRACT FROM AUTHOR]

In recent years, catalytic degradation driven by mechanical‐energy tribocatalysis has gained much attention. Point defects play very important on the catalytic activity of ferroelectric oxides. In this study, we focus on the influence of oxygen vacancies on the catalyst performance of ferroelectric oxide KSr2Nb4TaO15 (KSNT) with a tetragonal tungsten bronze structure. The concentration of oxygen vacancies is modified by sintering atmosphere. The KSNT sintered in N2 atmosphere exhibits the best tribocatalytic degradation efficiency of 96.7% within 2 h for degradation rhodamine B due to high concentration of oxygen vacancies. The excellent degradation efficiency is attributed to the defect energy level of KSNT and high electron–hole separation efficiency. This work reveals the relationship between oxygen vacancies and tribocatalysis efficiency, which is helpful to design and modify the new ferroelectric oxides for tribocatalysis. [ABSTRACT FROM AUTHOR]

This study aims to comparatively investigate the morphological and optical characteristics of zinc oxide nanoparticles as a function of the preparation conditions. A series of ZnO nanoparticles were synthesized by facile precipitation method at constant temperature, by varying the zinc sources (zinc acetate, zinc nitrate and zinc chloride) or the precipitant nature (hexamethylenetetramine, urea). The structural, morphological and optical attributes of the prepared ZnO samples were assessed by SEM, XRD, FTIR, UV–Vis and photoluminescence analyses. The morphology of the achieved samples varies from spiky sticks to hexagons or foils with irregular shapes, observing that urea favour the development of two- or three-dimensional ZnO nanostructures, while hexamethylenetetramine predominantly triggered the formation of highly organized one-dimensional structures. The XRD patterns of all ZnO samples matches zincite crystalline hexagonal phase and the evaluation of crystallite size revealed higher values for the samples prepared in the presence of hexamethylenetetramine (HMTA). The optical band gap of ZnO NPs, as estimated from the UV–Vis absorption spectra, varied slightly from 3.13 to 3.21 eV, while fluorescence investigation proves that samples prepared with urea precipitant have a lower rate of charge recombination. Tests on the photocatalytic degradation of malachite green dye under UV light irradiation demonstrated that the dynamics of photogenerated charge carriers play a significant role in the photocatalytic performance of ZnO samples. [ABSTRACT FROM AUTHOR]

This study aims to elucidate the possible application of cobalt aluminate nanoparticles (CoAl 2 O 4) as a photocatalyst for the removal of organic dyes. The sol-gel method was employed to synthesise Nd x /CoAl 2 O 4 nanoparticles with varying weight percentages (x = 0.0, 0.2, 0.4, and 0.6 wt %). The experimental investigation focused on the photocatalytic destruction of colour, employing a visible light irradiation source. The structural and optical properties of the synthesised nanoparticle were examined through various analytical techniques, including X-Ray Diffraction (XRD), Ultra Violet-Diffuse Reflectance Spectroscopy (UV-DRS), Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray spectroscopy (EDX), Tunnelling Electron Microscopy (TEM), and X-ray Photoelectron Spectroscopy (XPS). The cubic spinel structure was confirmed through the study of the X-ray diffraction (XRD) pattern of the Nd x /CoAl 2 O 4 nanoparticles. For the compositions x = 0.0, 0.2, 0.4, and 0.6, the nanoparticles exhibited average crystallite sizes of 23.73, 22.99, 21.69, and 21.65 nm, respectively. The synthesised nanoparticle exhibited heterogeneous photocatalytic potential when employed as a model pollutant for the oxidative destruction of crystal violet dye. The experimental findings validated that the CoAl 2 O 4 nanoparticle exhibited a dye degradation rate of 64 % during a 100-min timeframe. Additionally, the 0.6 wt % Nd CoAl 2 O 4 nanoparticle shows a quick dye degradation rate of 91 % for crystal violet dyes when exposed to visible light sources. Hence, the synthesised nanoparticle exhibits catalytic activity and holds potential for utilisation in the treatment of hazardous contaminants in industrial wastewater. [ABSTRACT FROM AUTHOR]

Herein, the Mg-S co-doped TiO2 nanoparticles (NPs) were synthesized by the sol-gel method, and their photocatalytic activity of MB (methylene blue) dye was examined under simulated visible light. X-ray diffraction patterns of Mg-S co-doped TiO2 reveal an average crystallite size of 19.3 nm. Moreover, results showed that Mg/S co-doped TiO2 NPs had pure anatase structures with spherical morphology. The band gap energy Mg/S co-doped TiO2 was decreased from 3.12 to 2.78 eV by adding the doping and codoping of Mg and S into TiO2 NPs. The Mg/S co-doped TiO2 NPs showed excellent photocatalytic activity compared to pristine TiO2, Mg-TiO2, and S-TiO2 NPs. The maximum degradation efficiency of MB was achieved at 94.8% for Mg/S co-doped TiO2 NPs. Meanwhile, the possible photocatalytic mechanism of photocatalysts was discussed. Different weight percentages of Mg/S co-doped TiO2 were used to investigate the effect of the Ag concentration on antimicrobial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), and the maximum antibacterial activity was achieved by 24 mm and 22 mm for TiO2 NPs membrane doped and co-doped with Mg/S. The current investigation delivers a promising strategy to promote photocatalytic activity to eliminate waterborne contaminants. [ABSTRACT FROM AUTHOR]

ABSTRACT The biogenic synthesis of silver nanoparticles (AgNPs) with leaf extract Abution indicum was done, and those were characterized by ultraviolet–visible spectroscopy (UV–vis), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), powder X‐ray diffraction (PXRD), field emission scanning electron microscopy (FESEM) and transmission electron microscope (TEM) with energy‐dispersive X‐ray (EDX) spectroscopy. The analysis by UV–vis spectroscopy showed a peak of 450 nm, and DLS and zeta potential were utilized to determine the size distribution of the biosynthesized Abution indicum–AgNPs (AI‐AgNPs) with a size range of 24–37 nm, and the X‐ray diffraction peak 38.096o was used to confirm that the crystalline structure of AI‐AgNPs. Furthermore, the antipathogenic effect of synthesized AgNPs and standard antibiotic (Ciprofloxacin) as studied the positive control in different types of bacterial pathogens likes Staphylococcus aureus and Escherichia Coli, with the zone of inhibition values of 9 mm. The synthesized AgNPs displayed excellent photocatalytic activity against reactive blue under sunlight than a UV light irradiation, and maximum degradation of 43% was achieved with 66 min of reaction time. In view of promising activity, the AgNPs could be used photocatalyst for the degradation of dyes in wastewater, and pomegranate leaf extract can be applied as eco‐benign and cost‐effective approach for AgNPs synthesis. Hence, the current findings suggest that Abutilon indicum is a valuable source for tailoring the potential of AgNPs toward various enhanced biological, photocatalytic, and adsorption activities. Consequently, the plant biological molecule‐mediated synthesized AI‐AgNPs could be excellent contenders for future therapeutic applications. [ABSTRACT FROM AUTHOR]

The constant increase in population and as a result increase in industrial activities in many areas, such as textiles, cosmetics, leather, polymers, and food processing leads to the contamination of water sources with different dyes. Thus, the removal of dyes from contaminated water sources to make water reusable is the utmost requirement of the time in order to get environmental sustainability. The reason of removal is that many dyes and pollutants present in dyeing wastewater from industries have detrimental impacts on plants, wildlife, and humans. To lessen the negative effects of dye wastewater on the environment and living beings, it should be processed first to remove un-wanted components before being released in the water sources. However, due to some drawbacks of dye removal technologies, it is challenging to settle on a single solution that addresses the current dye effluent problem to make water clean. In the current work, we tried our best to elaborate different methods adopted for the treatment of dyes polluted wastewater with respect to their implementation along with drawbacks and advantages. [ABSTRACT FROM AUTHOR]

A one‐pot synthesis of plasmonic gold‐modified TiO2 nanocomposites is reported by using glucose reduction of HAuCl4 in presence of titanium tetraisopropoxide. The resulting nanocomposites are characterized by thermal‐gravimetric analyses, X‐ray diffraction combined with X‐ray fluorescence and photoelectron spectroscopies. A binary system of β‐TiO2 and anatase phases is obtained for low Au content while only anatase form is favored when the initial Au rate rises. This investigation also suggests the inclusion of gold in the TiO2 structure. Although the optical bandgap of the different nanocomposites remains around 3 eV, the increase of Au content induces a shift of both valence and conduction edge bands to lower energy levels. The photocatalytic activity of TiO2/Au nanocomposites is assessed through the decolorization of different cationic and anionic dyes as model compounds. Regarding rhodamine and methylene blue dyes, the sample TiO2 modified with 3.5 wt% of Au presents the best performance. The relation between the structure of the nanocomposites and their capacity to degrade pollutants is discussed. [ABSTRACT FROM AUTHOR]

Photocatalysis is an effective environment-friendly technique that has emerged as a viable option for the degradation of a wide range of contaminants. In most cases, natural sunlight has been used in photocatalysis which makes it cost-effective. Also, it has emerged as an efficient method for degrading harmful toxic chemicals which are hard to degrade by any other alternatives. Various metals and metal compounds like oxides, sulphides, and carbides are used as photocatalysts to increase the efficiency of degradation. The common metal compounds known as ceramics are ZnO, TiO2, MoS2, ZnS, Fe2O3, SiC, CdS, WO3, SrTiO3, SnO2, NiO, and ZrO2. These materials are also known as semiconductors and are used as effective photocatalysts to degrade harmful and toxic environmental pollutants. This review discusses various ceramic photocatalysts, their application, photocatalysis mechanism, and degradation of various organic and inorganic compounds in actual wastewater. The use of photocatalysts in the treatment of persistent organic and inorganic pollutants in wastewater, such as pharmaceutical compounds, pesticides, dyes, oil, microplastics, and heavy metals is also explored. [ABSTRACT FROM AUTHOR]

Perovskites can absorb solar energy and are extensively used in various catalytic and photocatalytic reactions. However, noble metal particles may enhance the catalytic, photocatalytic, and antibacterial activities. This study demonstrates the cost-effective green synthesis of the photocatalyst perovskite LaMnO3 and its modification with noble metal Ag nanoparticles. The green synthesis of nanocomposite was achieved through a hydrothermal method employing aqueous extract derived from Citrus limon (L.) Burm peels. The properties of fabricated perovskites LaMnO3 and LaMnO3-Ag nanocomposites were evaluated and characterized by Ultraviolet-Visible spectroscopy (UV-Vis), Diffuse Reflectance Spectroscopy (DRS), X-ray diffraction (XRD), Fourier-Transform Infrared Spectroscopy (FT-IR), High-Resolution Transmission Electron Microscopy (HRTEM), Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray spectroscopy (EDX) and Brunauer–Emmett–Teller (BET) surface area techniques. The particle size distribution % of LaMnO3 and LaMnO3-Ag was observed to be 20 to 60 nm after using TEM images. The maximum percentage size distribution was 37 nm for LaMnO3 and 43 nm for LaMnO3-Ag. In addition, LaMnO3-Ag nanocomposite was utilized as a photocatalyst for the degradation of Rose Bengal (RB) dye and its antibacterial activities against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). The surface area and band gap for perovskite LaMnO3 nanoparticles were calculated as 12.642 m2/g and 3.44 eV, respectively. The presence of noble metal and hydrothermal-bio reduction significantly impacted the crystallinity. The BET surface area was found to be 16.209 m2/g, and band gap energy was calculated at 2.94 eV. The LaMnO3 nanocomposite with noble metal shows enhanced photocatalytic effectiveness against RB dye (20 PPM) degradation (92%, R2 = 0.995) with pseudo-first-order chemical kinetics (rate constant, k = 0.05057 min−1) within 50 min due to the ultimate combination of the hydrothermal and bio-reduction technique. The photocatalytic activity of the LaMnO3-Ag nanocomposite was optimized at different reaction times, photocatalyst doses (0.2, 0.4, 0.6, and 0.8 g/L), and various RB dye concentrations (20, 30, 40, and 50 ppm). The antibacterial activities of green synthesized LaMnO3 and LaMnO3-Ag nanoparticles were explored based on colony-forming unit (cfu) reduction and TEM images of bacterial and nanoparticle interactions for S. aureus and E. coli. An amount of 50 µg/mL LaMnO3-Ag nanocomposite was sufficient to work as the highest antibacterial activity for both bacteria. The perovskite LaMnO3-Ag nanocomposite synthesis process is economically and environmentally friendly. Additionally, it has a wide range of effective and exclusive applications for remediating pollutants. [ABSTRACT FROM AUTHOR]

Herein, we successfully modified wood sponge (WS) with Fe3O4 (MWS) to enhance its ability to adsorb five different oils, eight organic solvents, metal ions, and degrade methylene blue (MB) from wastewater. MWS, possessing over 96% porosity, exhibited remarkable sorption capacities of 26.79 g g− 1 for CCl4 and 21.00 g g− 1 for pump oil. Notably, MWS maintained high sorption capacity even after repeated use. Furthermore, MWS effectively removed toxic metal ions including As3+, Cr6+, and Pb2+ from real industrial wastewater, at pH 4 and 50 °C to levels suitable for drinking water. Also, MWS demonstrated excellent photocatalytic properties for degrading methylene blue dye. The photodegradation process involved the generation of superoxide anion radicals and the participation of hydroxyl radicals. The magnetic properties of MWS allow for easy remote retrieval using a magnet, making it a cost-effective and reusable solution for environmental remediation. [ABSTRACT FROM AUTHOR]

A series of europium doped lanthanum oxychloride samples were prepared through solid state method which were utilized as an electrode material and also as photocatalyst. The compounds form tetragonal phase having P4/nmm space group (No. 129). The sample's energy band-gap vary in between 4.14 and 4.35 eV. With a carbon paste electrode in a 0.1 M KOH electrolyte, Cyclic Voltammetry (CV) and Electrochemical (AC) Impedance Spectroscopy are performed. Results reveal that the sample synthesized can be an electrode material for sensing tin in alkaline medium in the concentration range of 1 to 5 mM. Also, the samples are considered to be photocatalyst for the decolourization of Rhodamine.B (Rh.B) dye in aqueous medium concentration of 10 ppm using UV light irradiation. LaOCl:Eu3+ sample as catalyst be able to degrade the Rh.B dye to an extent of 90% in 60 mins. These results demonstrated the relevance of synthesized compound for sensor and photocatalytic applications. Novelty: In this article, the La1-xEuxOCl (0.00 ≤ x ≤ 0.09) synthesised compounds were characterized for morphological nature, structural feature, and functional group analysis with band gap energies. Very particularly for the first time the synthesized samples have undergone preliminary research into their possible usage as electrodes for sensor applicability involving the detection of Tin in alkaline media. Moreover, the samples offered improved photocatalytic effectiveness for the decolourization of Rhodamine.B dye under the UV light irradiation. [ABSTRACT FROM AUTHOR]

Erythrosine B (EB) is a dye widely used in the food and textile industries. Despite many studies that have been proposed in the literature about the electrochemical oxidation of dyes, few studies considered such recalcitrant xanthene compound, although it has been recognized as a threat to health and the environment. Then, this study investigates the oxidation of EB by a homogeneous electro-Fenton process using iron (II) sulfate heptahydrate as a catalyst, carbon felt cathode, and Ti/RuO2 anode. The treated synthetic wastewater contains 100 mg L−1 of EB and has a pH = 3. The effects of three independent variables have been considered for process optimization, such as applied current intensity (0.1–0.5 A), iron concentration (1–10 mM), and stirring rate (100–1000 rpm). Their interactions were investigated considering response surface methodology (RSM) based on Doehlert design as optimization method. EB removal efficiency and energy consumption were considered as model responses after 30 min of electrolysis. Analysis of variance (ANOVA) revealed that the quadratic model was adequately fitted to the experimental data with R2 (0.9819), adj-R2 (0.9276), and low Fisher probability (< 0.0181) for the EB removal model, and R2 (0.9968), adj-R2 (0.9872) and low Fisher probability (< 0.0014) relative to the energy consumption model, suggesting a robust statistical significance. The energy consumption model significantly depends on current density, as expected. The foregoing results obtained by RSM led to the following optimal conditions for EB degradation: current intensity of 0.2 A, iron concentration of 9.397 mM, and stirring rate of 500 rpm, which gave a maximum decolorization rate of 98.15% with a minimum energy consumption of 0.74 kWh m−3 after 30 min of electrolysis. The competitiveness of the electro-Fenton process has been confirmed by the literature analysis proposed as well as by the preliminary economic analysis proposed in the second section of the study. [ABSTRACT FROM AUTHOR]

Piezocatalysis presents an innovative catalytic technique that utilizes the piezoelectric properties of catalysts to convert mechanical energy into electrical energy, thereby driving chemical processes. While various methods for driving piezocatalytic reactions have been developed, there is a notable absence of comprehensive research on piezocatalytic performance across multiple methods. In this context, this study explores the potential of (1- x)Pb(Ni 1/3 Nb 2/3)O 3 - x PbTiO 3 (PNN-PT) based catalysts as efficient piezocatalysts using both ultrasonic vibration and ball milling. The optimal reaction rate constants of the PNN-PT piezocatalyst under ultrasonic vibration and ball milling are found to be 0.0775 min−1 and 0.0265 min−1, respectively. Notably, PNN-PT-based catalysts exhibit outstanding catalytic activity up to ultra-high substrate concentrations (65 mg/L), suggesting possible industrial applications. The exploration of the reaction mechanism indicates that •OH is the main reactive radical, the catalytic reaction activity demonstrates a direct relationship with •OH quenching, and the high •OH generation rate of PNN-PT further illustrated their suitability as environmental purification catalysts. [ABSTRACT FROM AUTHOR]

Semi-rigid V-shaped bis(N,N-trimellitoyl)-4,4′-oxydianiline linker was designed to construct a novel mesoporous cobalt (II) metal organic framework (Co-MOF). Optical band gap of 3.23 eV was obtained using a Tauc formula, which confirms the semiconducting property of the synthesized Co-MOF. Further, the resulting Co-MOF, as photocatalyst, was investigated in environmental application for the reduction of toxic Cr (VI) to less toxic Cr (III) as well as in the degradation of organic rhodamine B (Rh B) dye in an aqueous medium under natural sunlight. As pH value is essential for the Cr (VI) reduction reaction, thus control experiment was conducted in the acidic pH range 2–6, where 90.76, 77.23 and 37.43% of reduction was observed at pH of 2, 4 and 6, respectively. Furthermore, the degradation of Rh B dye was also performed, where 98.89% degradation obtained within 90 min. The recyclability test was also assessed for Cr (VI) reduction reaction at pH 2 and for degradation of Rh B. [ABSTRACT FROM AUTHOR]

The development of a fluorescent pH sensor and the treatment of wastewater with nanoparticles are both critical topics. Variations in pH impact the morphology and subsequent properties of nanoparticles, affecting their utilization in various fields, while using nanoparticles offers an improved approach for treating industrial waste. The present study examines the effects of these variables on biologically produced nitrogen-doped carbon quantum dots (NCQDs). The synthesis was achieved through a hydrothermal process using Rubus niveus leaf extract as a precursor. UV-Vis spectroscopy analysis revealed absorption spectra over a wide range from 200 nm to 800 nm, with prominent peaks at 236 nm and 392 nm. Additionally, the direct energy band gap of the NCQDs was found to be 3.65 eV. SEM imaging displayed flower-shaped particles, and FT-IR analysis indicated the presence of amide, CHO, N-H, and C-N functional groups. The XRD pattern revealed that the surface morphology of NCQDs is amorphous in nature. A significant response in fluorescence intensity with varying pH values was observed, confirming the potential of NCQDs as pH sensors. The reaction kinetics of Rhodamine-B (Rh-B) dye was analyzed to assess the potential of NCQDs for dye degradation, revealing pseudo-first-order kinetics with a correlation coefficient of 0.80. [ABSTRACT FROM AUTHOR]

The current study focused on the exploration of bacterial community in heavy metal contaminated soil using culture dependent and independent approaches that might be applied to the bioremediation process. A total of 150 bacterial colonies were examined from the heavy metal-contaminated soil at initial level, and 25 isolates were chosen for further examination. Finally, twelve strains were chosen for future research based on their high levels of heavy metal resistance. The 10 bacterial strains i.e.,1K-10K were then characterized on the basis of their morphology and microscopic analysis. The morphological and biochemical characteristic relied on the basis of Bergey's manual of bacterial classification that 1K as Pseudomonas sp., 2K as Enterobacter sp., 3K as Streptococcus sp., 4K as Staphylococcus sp.,5K as Staphylococcus sp., 6K as Pseudomonas sp., 7K as Micrococcus sp., 8K as Staphylococcus sp., 9K as Staphylococcus sp. & 10K as Staphylococcus sp. In metagenomics analysis, the most prevalent bacteria present in samples were "Actinobacteria, Proteobacteria, Acidobacteria, Pseudomonas Cyanobacteria, Bacteriodes, and Sphingomonas. Among the 29 identified phyla, Chloroflexi and Tenericutes were the most dominant phyla and their relative abundance ranged from 0.75-1.00. While, on the genera level, the most abundant genera were Blautia, Rhodoplanes followed by Prevotella and Arenimonas. The relative abundance of these genera ranged from 0.75% to 1.00%. Depending on the relative abundance of taxons, the results of this study showed Proteobacteria, Synergistetes and Bacteriodes were most abundant phylum while the least abundant phylum present in heavy metal contaminated soil was Chlamydia and Tenericutes. Screening of soil-based libraries using functional and sequence-based specifications, which has disclosed information on soil microbial communities, has made it possible to identify new microbial communities. Thus, the culture dependent and independent approaches revealed that even heavy metal contaminated soil compose of diverse group of bacterial community that could be explored for bioremediation purposes. [ABSTRACT FROM AUTHOR]

Ferrite-based photocatalysts have raised as potent agents for breaking down organic pollutants in wastewater treatment. However, the challenge of developing an environmentally sustainable and economically viable photocatalyst with heightened efficacy persists. In this study, we prepared a green biochar-supported ZnFe2O4 (BC-ZnFe2O4) composite catalyst through a simple calcination method using waste banana peel (Macho plantain). The physicochemical properties of the prepared catalysts were thoroughly characterized, encompassing phase structure, surface morphology, purity, size, optical features, and charge separation efficiency. The characterization results confirmed that the ZnFe2O4 had a specific crystal structure in the composite. Microscopic analysis showed that the BC-ZnFe2O4 composite had a consistent cubic-like shape, with grains sized between 60–80 nm. Importantly, these BC-ZnFe2O4 composite had a direct band gap of about 2.29 eV, making them suitable for photocatalytic reactions. The photocatalytic methylene blue (MB) degradation experiments revealed that BC-ZnFe2O4 (91.08%; k = 0.3938 min−1) exhibits a superior photocatalytic activity compared to its pure BC-ZnO (75.26; k = 0.2129 min−1) counterparts within 100 min visible light irradiation. The excellent photocatalytic performance of the BC-ZnFe2O4 composite was due to the combined effect of the biochar and ZnFe2O4, which generated reactive oxygen species during the degradation process. In addition, the as-prepared BC-ZnFe2O4 composite demonstrated remarkable catalytic stability throughout multiple reaction cycles, making it suitable for sustained degradation of dye pollutants. Considering the outstanding performance of BC-ZnFe2O4 composite for the photocatalytic reaction, we believe that BC-ZnFe2O4 holds significant potential for purifying pollutants in various applications. [ABSTRACT FROM AUTHOR]

In this study, we synthesized mesoporous silver-titanium (Ag/TiO2) through green synthesis approach using mangosteen pericarp extract, which subsequently can act as both adsorbent and photocatalyst materials. Additionally, we investigated and compared the degradation of methylene blue (MB) using mesoporous Ag/TiO2 under dark conditions, visible light irradiation, and both dark-light conditions to analyze the adsorption-photocatalysis activity. The achieved mesoporous structure in this study offers distinct advantages as an adsorbent. Moreover, the addition of silver (Ag) to titanium dioxide (TiO2) shows promise in enhancing photocatalytic activity in MB degradation, which enhances photocatalytic activity in the visible light region due to its localized surface plasmon resonance (LSPR), which excites more electrons, resulting in increased MB degradation. The highest degradation percentage of 97.08 % was obtained using a dark-light degradation mechanism, demonstrating that the synthesized mesoporous Ag/TiO2 has potential as an effective integrated adsorbent-photocatalyst material for MB dye degradation.

The dye removal effect of the anisotropic polysaccharide-ZIF-8 aerogel via adsorption and catalysis was observed, highlighting the great potential of the hybrid aerogel as a highly effective, sustainable, and low energy-consuming environmental remediation material. The hybrid aerogel with remarkable mechanical strength has excellent prospects for regeneration to extend its lifespan. [Display omitted] Assembling microscopic metal–organic frameworks into macroscopic polymeric scaffolds to develop highly renewable materials has been a promising yet challenging area of research. Herein, chitosan (CS) blended with nano-cellulose (NC) was unidirectionally transformed into an aerogel with oriented macropores and then biomineralized with zeolite imidazolate frameworks-8 (ZIF-8) to form a hierarchical structured chitosan-nanocellulose/zeolite imidazolate frameworks-8 (CS-NC-ZIF-8) hybrid aerogel. Incorporating ZIF-8 significantly increases the versatility and mechanical strength with a Young's modulus of 14.18 MPa of the CS-NC aerogel. The incorporation of ZIF-8 into the aerogel not only enhances its adsorption capacity for methylene blue, rhodamine B, acid fuchsin, and methyl orange, but also facilitates the generation of electrons from water that can be transferred to degrade > 90 % of malachite green within 90 min in each catalytic cycle, and this capability was maintained for at least 10 consecutive cycles. Remarkably, the hybrid aerogel was highly renewable after the adsorption of cationic dyes and catalytic removal of malachite green. With its facile production process, high removal efficiency, affordable and green nature, and excellent regeneration feasibility, the CS-NC-ZIF-8 aerogel stands as a promising solution for addressing challenges associated with dye-contaminated water treatment. [ABSTRACT FROM AUTHOR]

In this research, the visible light active performance of Bi2ZnB2O7 (BBZO) was significantly enhanced through the formation of a composite with few layer MoS2. The resultant MoS2@BBZO catalyst was employed in both photocatalysis and photodetector applications. Comprehensive structural and morphological analyses of the MoS2@BBZO catalyst were conducted using x-ray diffraction, Raman spectroscopy, field-emission scanning electron microscopy (FE-SEM), and transmission electron microscopy. The estimated band gaps of BBZO and the composite were found to be 2.8 eV and 1.74 eV, respectively. Rhodamine B degradation studies demonstrated that the catalyst achieved 75% degradation within 30 min. Additionally, the photodetector application was investigated, revealing rapid photo-switching capabilities and an increased photocurrent. [ABSTRACT FROM AUTHOR]

Pollutants from industrial effluents create a wide problem concerning harm to humans, the environment, and climate. This work focuses on developing TiO2 nanowires (NWs) for photocatalytic activity and water treatment applications. The three different temperatures calcined TiO2 nanowires were synthesized via hydrothermal method followed by subsequent calcination at various temperatures. The TiO2 nanowires were analyzed using techniques such as UV spectroscopy, scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), TEM, and BET to investigate their structural, morphological, and surface properties. The FE-SEM and TEM micrographs of TiO2 nanomaterial show well-defined wire morphology with an average size of 150–200 nm. All the synthesized nanowires show a significant band gap in the range of 3.42–3.56 eV associated with the UV region. The calculated BET surface area of the formed TiO2 nanowires for T0, T1, T2, and T3 is 4.84, 124.5, 19.28, and 23.51 m2/g respectively. The results demonstrate its potential as an efficient and sustainable photocatalysis and dye degradation solution. The efficiency of the nanowires was analyzed through photocatalytic degradation experiments using model organic pollutants from nitrophenol under UV light irradiation. The outcomes show that the low-temperature calcined TiO2 (T1) nanowires efficiently degraded PNP (para-nitrophenol) pollutants up to 76% in low pollutant concentration at 40⁰C in a UV visible cabinet and the percentage recovery of Catalyst is around 98%. due to their high surface area 124.5m2/g). The nanowires exhibit excellent photocatalytic activity, enabling effective degradation and mineralization of pollutants. Its ability to efficiently remove contaminants under UV or visible light irradiation makes it a sustainable and effective solution for treating wastewater from diverse industrial effluents. [ABSTRACT FROM AUTHOR]