Environmental Remediation Research Articles

Simulation of Heavy Metal Removal in Irrigation Water Using a Shell-Derived Biochar-Integrated Ecological Recycled Concrete

Water pollution intensifies water scarcity and poses a significant threat to ecosystems and human health. Construction waste generated by rapid urbanization also imposes a considerable burden on the environment. Fortunately, a large portion of this waste can be efficiently converted into recycled aggregates and reused in various fields including environmental remediation. In this study, three types of eco-recycled concretes (ERC) (Control-ERC, Biochar-ERC-1, and Biochar-ERC-2) were formulated by integrating shell-derived biochar with recycled aggregates. The porosity and water permeability of these concretes were characterized, and their efficacy evaluated in treating polluted water with six primary heavy metals (HMs), i.e., cadmium (Cd), chromium (Cr), arsenic (As), manganese (Mn), lead (Pb), and copper (Cu). Biochar addition significantly enhanced the continuous porosity and water permeability of the concrete, and substantially enhanced its adsorption capacity of HMs. Specifically, Biochar-ERCs removed over 90% of As, Cd, and Mn, and achieved a removal rate exceeding 60% for other HMs, surpassing the performance of Control-ERC. This study not only lays a solid foundation for the wide application of Biochar-ERCs in the field of environmental protection and remediation, but also provides strong technical support and practical examples for advancing the circular economy model of converting waste into resources while addressing the challenge of global water scarcity.

Covalent integration of polymers and porous organic frameworks

Covalent integration of polymers and porous organic frameworks (POFs), including metal-organic frameworks (MOFs), covalent organic frameworks (COFs) and hydrogen-bonded organic frameworks (HOFs), represent a promising strategy for overcoming the existing limitations of traditional porous materials. This integration allows for the combination of the advantages of polymers, i.e., flexibility, processability and chemical versatility etc., and the superiority of POFs, like the structural integrity, tunable porosity and the high surface area, creating a type of hybrid materials. These resulting polymer-POF hybrid materials exhibit enhanced mechanical strength, chemical stability and functional diversity, thus opening up new opportunities for applications across a large variety of fields, such as gas separation, catalysis, biomedical applications, environmental remediation and energy storage. In this review, an overview of synthetic routes and strategies on how to covalently integrate different polymers with various POFs is discussed, especially with a particular focus on methods like polymerization within, on and among POF structures. To investigate the unique properties and functions of these resultant hybrid materials, the characterization techniques, including nuclear magnetic resonance spectroscopy (NMR), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), transmission electron microscopy (TEM) and scanning electron microscopy (SEM), gas adsorption analysis (BET) and computational modeling and machine learning, are also presented. The ability of polymer-POFs to manipulate the pore environments at the molecular level affords these materials a wide range of applications, providing a versatile platform for future advancements in material science. Looking forward, to fully realize the potential of these hybrid materials, the authors highlight the scalability, green synthesis methods, and potential for stimuli-responsive polymer-POF materials as critical areas for future research.

Recent Advances in Single‐Atom Catalyst for Solar Energy Conversion: A Comprehensive Review and Future Outlook

AbstractSingle‐atom catalysts (SACs) are becoming increasingly recognized as highly promising catalytic materials, distinguished by their exceptional atomic efficiency, superior selectivity, and elevated activity levels. This review offers a detailed and comprehensive overview of the recent advancements in SACs, focusing on synthesis strategies, photocatalytic energy conversion applications, and advanced characterization techniques. Various synthetic approaches for fabricating atomically dispersed catalysts are elaborated concisely, emphasizing the importance of achieving precise atomic regulation on compatible supports to ensure strong metal–support interactions. Furthermore, the advanced characterization techniques by analytical tools are illustrated for a deep exploration of catalytic activity and mechanistic insights into uniformly dispersed SACs. Specifically, different kinds of support materials such as metal–organic frameworks (MOFs), their subset zeolitic imidazolate frameworks, and graphitic carbon nitride (g‐C3N4) with diverse coordination and electronic environments are examined. Further, advances in computational techniques and machine learning are transforming SACs development by improving predictive accuracy and reducing trial‐and‐error methods, thereby accelerating the discovery of stable and active catalysts. Finally, current challenges and prospects of SACs based on MOFs, and g‐C3N4 are addressed, providing valuable insights for the continued development and application of these catalysts in various industrial processes and environmental remediation efforts.

Phenolics over Zeolites and Related Materials—Biomedical and Environmental Applications

This work analyzes the following two aspects of zeolite applications: their application as carriers in delivery systems for phenolics applied as antioxidants or anticancer agents and the efficient removal of phenolic compounds from aqueous environments. The dual role of zeolites in increasing antioxidant bioavailability and environmental remediation is summarized, and perspectives on progress in zeolite adaptable applications are given. Special attention is given to theoretical methods that will guide future advanced delivery systems for biomedical applications, as well as serve as a focal point in designing multipurpose materials for comprehensive environmental solutions. Perspectives in both fields are discussed.

Porphyrin-Based Aluminum Metal-Organic Framework with Copper: Pre-Adsorption of Water Vapor, Dynamic and Static Sorption of Diethyl Sulfide Vapor, and Sorbent Regeneration

Metal–organic frameworks (MOFs) are hybrid inorganic–organic 3D coordination polymers with metal sites and organic linkers, which are a “hot” topic in the research of sorption, separations, catalysis, sensing, and environmental remediation. In this study, we explore the molecular mechanism and kinetics of interaction of the new copper porphyrin aluminum metal–organic framework (actAl-MOF-TCPPCu) compound 4 with a vapor of the volatile organic sulfur compound (VOSC) diethyl sulfide (DES). First, compound 4 was synthesized by post-synthetic modification (PSM) of Al-MOF-TCPPH2 compound 2 by inserting Cu2+ ions into the porphyrin ring and characterized by complementary qualitative and quantitative chemical, structural, and spectroscopic analysis. Second, the interaction of compound 4 with DES vapor was analyzed dynamically by the novel method of in situ time-dependent attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy at controlled humidity levels. The sorbent–adsorbate interactions, as analyzed by the shifts in IR peaks, indicate that the bonding includes the hydroxy O-H, carboxylate COO−, and phenyl groups. The kinetics of sorption obeys the Langmuir pseudo-first-order rate law. The pre-adsorption of water vapor by compound 4 at the controlled relative humidity under static (equilibrium) conditions yields the binary stoichiometric adsorption complex (Al-MOF-TCPPCu)1.0(H2O)8.0. The pre-adsorption of water vapor makes the subsequent sorption of DES slower, while the kinetics obey the same rate law. Then, static pre-adsorption of water vapor was followed by static sorption of DES vapor, and the ternary adsorption complex (Al-MOF-TCPPCu)1.0(H2O)8.0(DES)3.8 was obtained. Despite the pre-adsorption of significant amounts of water, the binary complex adsorbs a large amount of DES: ca. 36.6 wt. % (per compound 4). Finally, the ternary complex is facilely regenerated by gentle heating under vacuum. Compound 4 and related MOFs are promising for adsorptive removal of vapor of DES and related VOSCs from dry and humid air.

Concise Review of Light-Driven Micromotor Synthesis and its Environmental Applications

Light-powered micromotors are a new type of micromotor that can be used for water purification treatment. This paper focuses on the synthesis processes and its application in water remediation. This mini review will highlight the great potential of these light powered micromotor as well as the significance of preparing them for environmental applications. Photocatalytic micromotors or light-powered micromotors have been intensively researched over the last several years for several applications, such as environmental remediation, biomedicine and micropumps. It has been found that conventional wastewater treatment is commercially inefficient in water remediation. The emphasis then was on a new solution of using micromotor as a potential replacement for water remediation. Many studies have been carried out over the years on the synthesis of these light-powered micromotors, which revolves around the materials used, and applications. This paper, therefore, reflects on the advancement of light-powered micromotors and will be concentrating on the synthesis processes and its application in water remediation. This mini-review will highlight the great potential of these light-driven micromotors as well as the significance of preparing them for environmental applications.

Novel S-scheme based nanocomposite of MXene/V2O5 for environmental remediation towards sustainable development: An insight into influencing parameters.

In this study, a novel 2D/2D nanocomposite of MXene and V2O5 was synthesized using a facile hydrothermal approach for the efficient removal of crystal violet (CV), a textile dye from contaminated water to achieve Sustainable Development Goal (SDG) 14; "Save Lives Below Water". Here, the catalytic performance of pristine MXene was prominently boosted with the introduction of ball milled V2O5 as an electron generating agent. The degradation efficiency of synthesized nanocomposite significantly enhanced from 57 % to 92 %, 41 % to 76 % and 7 % to 58 % with an error of ±2 % as compared to pristine MXene at 10, 20 and 30 ppm concentrations of CV, respectively. The effective degradation of pollutants is ascribed to the electron-transfer via S-scheme based mechanism and helps in reducing recombination rate of photogenerated carriers, which could produce hydroxyl radicals ) as primary species for effectively degradation of pollutants. The superior performance of nanocomposite is attributed to: (i) the optimized surface charge (-27.8 mV), (ii) small value of charge transfer resistance (Rct = 1.3 Ω), (iii) enhanced value of carrier concentration (6.3 X 1032 cm-3), (iv) small recombination rate of excitons and (v) high specific surface area as compared to pristine samples. Moreover, to strengthen the findings, scavenger study and electron paramagnetic resonance (EPR) study were carried out and concluded that hydroxyl radicals ) are the primary species in the mineralization of CV dye. The values of lande g-factor are calculated using EPR plots which comes out to be 2.03 and 2.04 for and ) radicals, respectively and demonstrates the formation of free radicals during catalytic reactions. The Chemical Oxygen Demand (COD) analysis was carried out before and after the removal of CV using MV nanocomposite and confirms the reduction in COD of 81.60 %. The reusability experiment confirms stability of synthesized sample and provides a good shred for industrial applications in the treatment of wastewater and getting out cleaner productions and to save marine ecosystem.

Synthesis and Characterization of MgO-Fe₂O₃/γ-Al₂O₃ Nanocomposites: Enhanced Photocatalytic Efficiency and Selective Anticancer Properties

In the present work, we achieved the fabrication of MgO-Fe2O3/γ-Al2O3 NCs using a deposition–coprecipitation process. XRD, TEM, and SEM with EDX, XPS, FTIR, and PL spectroscopy were applied to examine the physicochemical properties of the samples. XRD analysis confirmed the successful incorporation of γ-Al2O3, MgO, and Fe2O3 phases. TEM and SEM images indicate that the nanocomposites exhibited an agglomerated morphology with spherical shapes and particle sizes in the range of 6–12 nm. EDX and XPS spectra revealed a composition of MgO-Fe2O3/γ-Al2O3 NCs. FTIR spectra identified characteristic vibrational bands corresponding to the chemical bonds present in the samples, confirming their successful synthesis. PL analysis showed the reduced recombination rate of electron–hole pairs and enhanced charge separation efficiency, which are important factors for improved photocatalytic activity. Photocatalysis results show that the MgO-Fe2O3/γ-Al2O3 NCs exhibited significantly higher photocatalysis efficiencies of 87.5% for Rh B and 90.4% for MB after 140 min, compared to γ-Al2O3 NPs and Fe2O3/γ-Al2O3 NPs. In addition, prepared MgO-Fe2O3/γ-Al2O3 NCs demonstrated superior stability after six runs. Biochemical data showed that the MgO-Fe2O3/γ-Al2O3 NCs exhibited significant toxicity toward A549 cancer cells while displaying low toxicity toward IMR90 normal cells. The IC50 values (µg/mL ± SD) for γ-Al2O3 NPs, Fe2O3/γ-Al2O3 NPs, and MgO-Fe2O3/γ-Al2O3 NCs were 16.54 ± 0.8 µg/mL, 14.75 ± 0.4 µg/mL, and 11.40 ± 0.6 µg/mL, respectively. These results suggest that the addition of Fe2O3 and MgO to γ-Al2O3 not only enhances photocatalytic activity but also improves biocompatibility and anticancer properties. This study highlights that the MgO-Fe2O3/γ-Al2O3 NCs warrant further exploration of their potential applications in environmental remediation and biomedicine.

Enhancing Pb Adsorption on Crushed Microplastics: Insights into the Environmental Remediation

This study investigates the pollution characteristics and environmental risks of crushed microplastics (MPs) generated during plastic recycling, emphasizing their adsorption capacity for heavy metals, particularly lead (Pb). SEM-EDS analysis revealed that crushed MPs exhibit significantly higher adsorption capacity than primary MPs due to their larger surface area and more available adsorption sites, including oxygen-containing functional groups. The adsorption behavior of MPs was influenced by key factors such as MP size, MP quantity, pH, salinity, and biofilm formation. Smaller MPs demonstrated higher adsorption efficiency, while elevated pH enhanced Pb adsorption. Conversely, increased salinity reduced adsorption due to competition for adsorption sites. Increasing MP concentrations improved Pb removal efficiency, but higher MP quantities led to a decrease in maximum adsorption capacity, demonstrating a trade-off between removal efficiency and adsorption capacity. Isothermal adsorption experiments revealed that Pb adsorption on MPs follows a multi-layer mechanism, best characterized by the Freundlich model. The adsorption capacity increased nonlinearly with Pb concentration and stabilized as surface sites became saturated. The formation of biofilms on MPs further enhanced their adsorption capacity by providing additional functional groups and facilitating multi-layer adsorption, increasing ecological risks. Adsorption kinetics were best described by pseudo-second-order and intra-particle diffusion models, indicating chemical adsorption and boundary layer diffusion as dominant mechanisms. Magnetic Fe3O4 nanoparticles demonstrated a high recovery efficiency of 99.3% for MPs, highlighting their potential for environmental remediation. However, the presence of adsorbed Pb slightly reduced recovery performance, emphasizing the need to optimize recovery conditions for maximum efficiency. These findings underscore the dual threat posed by crushed MPs: their capacity to adsorb and concentrate harmful substances, increasing ecological toxicity, and the challenges associated with their recovery. This research provides critical insights into mitigating MP pollution and developing effective recovery strategies under realistic environmental conditions.

Metal‐organic Framework‐derived NiO/ZnO Composites for Photoelectrocatalytic Reduction of Cr(VI)

AbstractNi/Zn‐MOF composites with photoelectrocatalytic (PEC) performance for Cr(VI) reduction were prepared via hydrothermal method and calcinating method. The as‐prepared NiO/ZnO composites exhibited uniform morphology. When being subjected to an external voltage of 0.7 V and irradiated with visible light for 120 min, the NiO/ZnO composite exhibited a Cr (VI) reduction efficiency of almost 100 %, outperforming ZnO and NiO counterparts. The effects of the content of NiO to ZnO and different calcination temperatures on PEC performance were also investigated. Additionally, elimination experiments results indicated that photo‐generated electrons (e−) play a crucial role in the catalytic reduction of Cr(VI). The notable enhancement in the photoelectrocatalytic performance can be credited to the applied bias voltage and the formation of a p‐n heterojunction between NiO and ZnO. Consequently, the NiO/ZnO nanocomposites exhibit significant potential for the PEC reduction of Cr(VI). This capability underscores the promise of NiO/ZnO nanocomposites for applications in the photoelectrocatalytic reduction of Cr(VI) and related environmental remediation processes.

Green Synthesis of Silver-Incorporated Rutile TiO2 for Enhanced Photocatalytic Degradation of Ciprofloxacin and Carmine G Dye Pollutants

Developing sustainable TiO2-based photocatalysts for environmental remediation is an increasingly significant area of research. However, a limited understanding of the long-term ecological impact of these photocatalysts poses a barrier to their practical and industrial-scale applications. To address this challenge, this work employed a green synthesis approach to prepare an Ag/TiO2 photocatalyst designed to improve environmental compatibility and enhance efficiency in pollutant degradation. Ag/TiO2 was synthesized using mushroom biomass as a natural capping to evaluate its effectiveness in the degradation of ciprofloxacin (CIP) and azo Carmine G dye (ACGD). The mushroom biomass served as a renewable cost-effective support for Ag incorporation, while the Ag modification of TiO2 could enhance the photocatalyst’s performance. Structural, chemical, and morphological characterization techniques were applied and showed that the Ag/TiO2 particles consisted of irregularly shaped nanoparticles. The CIP removal reached 82.46% after 300 min and ACGD removal efficiency went up to 83.64%. The enhanced performance is attributed to the unique electronic and structural properties of Ag-modified TiO2. This study highlights the potential of Ag/TiO2 synthesized via green methods as a high-performance photocatalyst for the effective remediation of pharmaceutical and dye pollutants in wastewater treatment applications.

Sustainable Green Synthesis of ZnO Nanoparticles from Bromelia pinguin L.: Photocatalytic Properties and Their Contribution to Urban Habitability

Aguama (Bromelia pinguin L.), a plant belonging to the Bromeliaceae family, possesses a rich content of organic compounds historically employed in traditional medicine. This research focuses on the sustainable synthesis of ZnO nanoparticles via an eco-friendly route using 1, 2, and 4% of Aguama peel extract. This method contributes to environmental sustainability by reducing the use of hazardous chemicals in nanoparticle production. The optical properties, including the band gap, were determined using the TAUC model through Ultraviolet–Visible Spectroscopy (UV–Vis). The photocatalytic activity was evaluated using three widely studied organic dyes (methylene blue, methyl orange, and rhodamine B) under both solar and UV radiation. The results demonstrated that the ZnO nanoparticles, characterized by a wurtzite-type crystalline structure and particle sizes ranging from 68 to 76 nm, exhibited high thermal stability and band gap values between 2.60 and 2.91 eV. These nanoparticles successfully degraded the dyes completely, with methylene blue degrading in 40 min, methyl orange in 70 min, and rhodamine B in 90 min. This study underscores the potential of Bromelia pinguin L. extract in advancing sustainable nanoparticle synthesis and its application in environmental remediation through efficient photocatalysis.

A Comprehensive Review of MXene-Based Emerging Materials for Energy Storage Applications and Future perspectives.

MXenes is a rapidly emerging class of two-dimensional (2D) materials. It exhibits unique properties that make it suitable for a wide range of applications. This review provides a comprehensive overview of the synthesis and processing techniques for MXenes including both bottom-up and top-down approaches. The synthesis of MXene-based composites is explored in detail focusing on MXene-carbon composites, MXene-metal oxides, MXene-metal sulfides, MXene-polymer composites and MXene-ceramic composites. Key properties of MXenes are examined including structural, electrical, morphological, optical, mechanical, chemical stability, electrical and thermal properties, conductivity, magnetic properties, dielectric charge and catalytic properties. Characterization techniques used to study these properties are also reviewed. Their 2D structure provides a high surface area and unique interlayer spacing, making MXenes ideal for applications in energy storage devices (like supercapacitors and batteries) where surface area and ion transport are critical for performance. The diverse applications of MXenes are presented emphasizing their use in batteries, catalysis, sensors, environmental remediation and supercapacitors. Special attention is given to the supercapacitor applications of MXenes of their potential in energy storage devices. Due to their high capacitance, fast charge/discharge rates, and excellent stability, MXenes are used in supercapacitors, lithium-ion batteries, and sodium-ion batteries.

Ferruginous hemeprotein HhuH facilitates the cadmium adsorption and chromium reduction in Stenotrophomonas sp. SY1.

Cadmium (Cd) and chromium (Cr) are frequently encountered toxicants, while iron (Fe) plays a crucial role in bacterial survival under conditions of heavy metal stress. However, intracellular Fe ion depletion by heavy metals leads to a state of Fe starvation. Therefore, it is imperative to investigate the mechanism through which bacteria maintain a balance between heavy metal detoxification and Fe homeostasis. This study demonstrates Cd(II) immobilization and Cr(VI) reduction abilities of Stenotrophomonas sp. SY1, while proteomics reveals the upregulation of heme metabolism in response to Cd(II) and Cr(VI) exposure. The expression of the heme-uptake system in Escherichia coli can enhance Cd(II) immobilization and facilitate Cr(VI) reduction. The ferruginous hemeprotein HhuH exhibits the ability to chelate Cd(II) and reduce Cr(VI). The presence of Cd(II) and Cr(VI) in strain SY1 initially led to Fe starvation. Subsequently, the hemeprotein HhuH facilitated Cd(II) adsorption and Cr(VI) reduction, thereby restoring normal cellular Fe homeostasis. Our findings explain the hemeprotein-mediated mechanism for Cd(II) adsorption and Cr(VI) reduction, providing further insights into the correlation between heavy metal and Fe metabolism.IMPORTANCEIron (Fe) is an indispensable trace element for many organisms, and virtually, all bacteria require Fe as a cofactor in enzymes to facilitate redox reactions involved in fundamental cellular processes during periods of heavy metal stress. Understanding bacterial response to Fe in heavy metal contamination is essential. Therefore, our study elucidates Cd(II) adsorption and Cr(VI) reduction processes mediated by the Fe-bearing hemeprotein HhuH. It is a unique trifunctional protein capable of chelating Cd(II) and reducing Cr(VI), demonstrating significant potential in the environmental remediation of heavy metals.

Enhanced Visible-Light Photocatalysis Activity of TiO2/Ag Nanocomposites Prepared by the Ultrasound-Assisted Sol–Gel Method: Characterization and Degradation–Mineralization of Cationic and Anionic Dyes

Coupling TiO2 with various elements could enhance its photocatalytic activity. In this study, an innovative ultrasound-assisted sol–gel method was used to synthesize TiO2/Ag(x%) by varying Ag–support mass (x = 9.3, 17.1, and 23.6%), followed by calcination at 450 °C for 30 min. The aim was to demonstrate that Ag compositing improves photoactivity under visible light (>400 nm). The synthesized photocatalysts were assessed for their effectiveness in the degradation and mineralization of Methylene Blue (MB) and Acid Orange 7 (AO7) using visible lamps emitting in the range of 400–800 nm. Characterization of the prepared photocatalysts was performed by using Raman spectroscopy, SEM/EDS, pHpzc, and UV–visible spectroscopy. Raman spectroscopy confirmed the predominance of the anatase phase in all the photocatalysts. The photodegradation efficiencies of the selected dyes, MB and AO7, reached 99% (pH 6) and 95% (pH 3) after 180 min of irradiation, respectively. The best performance for the degradation of the two dyes was observed with TiO2/Ag9.3%, showing optimal kinetics at this doping concentration. The improved photoactivity of the TiO2/Ag composite is due to a decrease in the recombination rate of electron/hole (e−/h+) and a decrease in the band gap from 3.13 to 2.49 eV. The mineralization rate of both dyes under visible light is about 9.3%, indicating the presence of refractory by-products that resist complete degradation. Under UVA irradiation, complete mineralization is obtained. This study confirms the potential of TiO2/Ag composite as a high-performance and cost-effective photocatalyst for solar environmental remediation, highlighting the role of silver in extending light absorption into the visible region and improving charge separation.

Formation and snake-eating like solubilization mechanisms of rhamnolipid vesicles for oil components and amino acids

Rhamnolipid vesicles hold significant potential across a wide range of applications, yet their formation mechanisms and selective solubilization of organic molecules remain elusive. Employing dissipative particle dynamics (DPD) simulations, this study delves deeply into these aspects, uncovering a stepwise formation pathway from dispersed monomers to complex multi-layer vesicle structures. The fusion and growth of three-layer structures were identified as crucial steps in the development of stacked vesicles. Notably, double-chain rhamnolipids (Rh-C10-C10) exhibited enhanced stability in self-assembled structures compared to their single-chain counterparts (Rh-C10). Through a detailed analysis of parameters such as relative concentration distribution, radial distribution function, and density fields, the solubilization process of rhamnolipid vesicles was found to resemble a “snake-eating” mechanism. We also analyzed the solubilization sites, amounts, and vesicle sizes, elucidating the selective solubilization mechanisms of rhamnolipids for representative polar and non-polar compounds in crude oil, anisole and 1-hexene. The selectivity of rhamnolipid vesicles in solubilizing organic molecules was primarily influenced by polar attraction and steric hindrance, which together determined their solubilization sites within the vesicles. Additionally, the solubilization behavior and properties of five types of amino acids within rhamnolipid vesicles were explored, demonstrating analogous solubilization patterns that correlated with amino acid polarity. These results provide a foundation for optimizing the application of rhamnolipid vesicles, paving the way for potential advancements in drug delivery, environmental remediation, and oil recovery processes.

Aspects of heat transfer hybridized micropolar water-based iron oxide and silver nanoparticles across a stretching bidirectional sheet with thermal radiation

The hybridization of nanoparticles enhances heat transfer, playing a crucial role in the development of advanced thermal insulation materials. These materials find applications across diverse fields, including electronics design, healthcare, environmental remediation, and automotive engineering. In light of this, the current study investigates the boundary layer flow and heat transfer of hybridized (Fe3O4−H2O) and (Ag−Fe3O4−H2O) micropolar nanofluids over an extending bidirectional sheet characterized by nonlinear thermal radiation. The boundary heating conditions are based on two types of thermal settings in the energy equation: prescribed surface temperature (PST) and prescribed heat flux (PHF). The resulting partial differential equations are then converted into ordinary differential equations using specific similarity variables. The mathematical equations are solved using the Chebyshev Collocation Method (CCM). Consequently, a variety of graphs and tables are displayed to deliberate the impact of the emerging parameters on the flow and heat transmission processes. At the end, the analysis reveals that an increase in the temperature gradient is higher in a non-isothermal situation as compared to an isothermal case with growth in the Prandtl number. The material property helps to reduce surface drag and heat transfer, whereas the magnetic field increases the skin friction coefficient.

Structural elucidation and environmental remediation potential of Ficus carica mediated synthesis of novel Eu3O4/rGO nanocatalyst

A novel europium oxide/reduced graphene oxide (Eu3O4/rGO) nanocatalyst was synthesized via green one pot method and green deposition method using Ficus carica leaves extract. The prepared nanocatalyst was characterized by UV–vis., FTIR, TGA, SEM, HR-TEM, and XRD. Band gaps of Eu3O4/rGO nanocatalyst by green one pot method and green deposition method were found 3.27 and 5.5 eV, respectively. The particle size of Eu3O4/rGO nanocatalyst determined by HRTEM was found 16.9 and 32.1 nm when prepared by using green one pot method and green deposition method, respectively. Significant morphology was observed in the SEM images of Eu3O4/rGO nanocatalysts; where Eu3O4 nanoparticles were observed to be dispersed on chunks of sheets of rGO. The catalytic activity of prepared nanocatalyst was performed against Methylene blue, Rhodamine B, and Ciprofloxacin. The green one pot method demonstrated highest levels of degradation activity 88, 75 and 54 % against MB, CIP, and Rh B pollutants present in wastewater, respectively and helps to achieve SDGs 6 and 13.

Advances in deep eutectic Solvent-Based synthesis of nanomaterials for environmental remediation

The application of eco-friendly deep eutectic solvents (DES) in the functionalization and synthesis of adsorbent materials has gained significant research interest in recent times. These materials, employed for treating polluted water primarily through degradation or adsorption, are emerging as sustainable alternatives to traditional technologies. However, the information regarding the functionalization and synthesis of adsorbent materials using DES is dispersed throughout the literature. This review aims to consolidate and clarify the extensive information available on the synthesis and functionalization of DES-based adsorbents, their application in water treatment as nanomaterials, and the future prospects of such technologies. DES presents an ideal alternative to conventional solvents for modifying and functionalizing adsorbents due to their lower toxicity, cost-effectiveness, and environmental friendliness. Most DESs effectively introduce desired functionalities and enhance the surface area of adsorbents, thereby greatly enhancing the removal of pollutants. This review compiles recent literature on the synthesis and modification of graphene oxides, carbon nanotubes, metal oxides, and other materials for the degradation/adsorption of pharmaceuticals, herbicides, dyes, pesticides, heavy metal ions, and other water contaminants. Besides this, DES-based nanomaterials have potential future applications in nanotechnology, nanofluids, nanocatalysts, biosensors, environmental remediation, among others. The anticipated exponential growth in these areas underscores the urgent need for such a review.

Encage the Carcinogens: A Metal–“Organic Cage” Framework for Efficient Polycyclic Aromatic Hydrocarbon Removal From Water

AbstractPolycyclic aromatic hydrocarbons (PAHs) are carcinogenic and persistent organic pollutants in water. Their removal is highly challenging for existing generic and nonspecific adsorbents, creating an urgent need for tailored solutions. Herein, a metal‐“organic cage” framework, MOF‐CC‐1, designed for the effective scavenging of PAHs from water is is introduced. This framework is constructed using a propeller‐shaped cofacial organic cage (CC‐1), equipped with three triazole pillars that coordinate with Ag(I) ions. The cationic MOF‐CC‐1 adopts a chiral (10,3)‐a srs net structure, spontaneously resolving into homochiral crystals. Additionally, bulk homochirality is achieved through chirality induction using chiral counteranions. MOF‐CC‐1 uniquely encapsulates diverse PAH molecules within the cavities of CC‐1, as confirmed by single‐crystal X‐ray diffraction, marking it as the first metal–“organic cage” framework with structural evidence of guest inclusion inside the organic cage linker. Further, MOF‐CC‐1 exhibits soft porosity, remaining nonporous to N₂ gas when compressed but expanding to encapsulate PAHs in solution. Moreover, MOF‐CC‐1 exhibits exceptional efficacy in scavenging ppb levels of PAHs from water. This work represents a significant advancement in utilizing organic cages as ligands toward MOF construction, paving the way for tailored adsorbents for PAH removal, and addressing a critical need for selective and efficient materials in environmental remediation.