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Metal organic frameworks (MOFs) are crystalline, three-dimensional structures with high surface areas and tunable porosities. Made from metal nodes connected by organic linkers, the exact properties of a given MOF are determined by node and linker choice. MOFs hold promise for numerous applications, including gas capture and storage. M2(4,4′-dioxidobiphenyl-3,3′-dicarboxylate)—henceforth simply M2(dobpdc), with M = Mg, Mn, Fe, Co, Ni, Cu, or Zn—is regarded as one of the most promising structures for CO2 capture applications. Further modification of the MOF with diamines or tetramines can significantly boost gas species selectivity, a necessity for the ultra-dilute CO2 concentrations in the direct-air capture of CO2. There are countless potential diamines and tetramines, paving the way for a vast number of potential sorbents to be probed for CO2 adsorption properties. The number of amines and their configuration in the MOF pore are key drivers of CO2 adsorption capacity and kinetics, and so a validation of computational prediction of these quantities is required to suitably use computational methods in the discovery and screening of amine-functionalized sorbents. In this work, we study the predictive accuracy of density functional theory and related calculations on amine loading and configuration for one diamine and two tetramines. In particular, we explore the Perdew–Burke–Ernzerhof (PBE) functional and its formulation for solids (PBEsol) with and without the Grimme-D2 and Grimme-D3 pairwise corrections (PBE+D2/3 and PBEsol+D2/3), two revised PBE functionals with the Grimme-D2 and Grimme-D3 pairwise corrections (RPBE+D2/3 and revPBE+D2/3), and the nonlocal van der Waals correlation (vdW-DF2) functional. We also investigate a universal graph deep learning interatomic potential's (M3GNet) predictive accuracy for loading and configuration. These results allow us to identify a useful screening procedure for configuration prediction that has a coarse component for quick evaluation and a higher accuracy component for detailed analysis. Our general observation is that the neural network-based potential can be used as a high-level and rapid screening tool, whereas PBEsol+D3 gives a completely qualitatively predictive picture across all systems studied, and can thus be used for high accuracy motif predictions. We close by briefly exploring the predictions of relative thermal stability for the different functionals and dispersion corrections. [ABSTRACT FROM AUTHOR]

Au@Ag core--shell composites were successfully fabricated on urchinlike covalent organic frameworks (COFs), providing a platform with numerous hot spots for the detection of two categories of emerging contaminants: sulfonamide antibiotics and nanoplastics, using surfaceenhanced Raman spectroscopy (SERS). Au seeds (~10 nm) were generated on the COFs, leveraging the reducing properties of the vinyl and imino groups within the framework. This ensured the growth of dense and uniformly distributed Ag nanoparticles. The COFs exceptionally large surface area (2324 m² g-1) and high adsorption capacity, significantly contributed to the enrichment and detection of trace pollutants. As a result, using a portable Raman spectrometer, limits of detection of 0.008 lmol L-1 for sulfamethoxazole and 0.029mg L-1 for polystyrene nanoplastics were achieved. [ABSTRACT FROM AUTHOR]

Owing to their high porosity, open metal sites, and huge surface area, metal–organic framework (MOF) materials are commonly employed in iodine adsorption processes. Bimetallic MOFs have drawn a lot of attention since mono-metal MOFs have been unable to keep up with the demand. Bimetallic MOF materials still have drawbacks, including limited adsorption capacity, extended adsorption time, poor stability, and poor selectivity, despite their positive performance in radioactive iodine capture. It has been therefore difficult to develop adsorbents with quick iodine adsorption rates and high iodine adsorption efficiency. This study investigated the adsorption properties of a series of bimetallic MOF-74 materials (Mn–Co-MOF-74, Mn–Zn-MOF-74, and Mn–Ni-MOF-74) for radioactive iodine, as well as their design and synthesis utilizing the reflux approach. It was discovered that the adsorption performance of Mn–Ni-MOF-74 for radioiodine was superior to that of the other two bimetallic MOF-74 materials. Using the bimetallic Mn–Ni-MOF-74 as a precursor, a variety of bimetallic MOF-74 derived carbon compounds (Mn–Ni-CX) were prepared by high-temperature pyrolysis. Simultaneously, the structure of the material and the iodine adsorption characteristics have been thoroughly studied. [ABSTRACT FROM AUTHOR]

In this study, the hydrogen storage properties of various synthetic zeolites, including Zeolite Y (FAU), Mordenite (MOR), ZSM-12 (MTW), and MCM-22 (MWW) are determined at 77 K and atmospheric pressure. The structures of the zeolites are characterized by XRD, ICP-OES, FE-SEM, TGA and N 2 adsorption-desorption isotherms. The results show that H-MCM-22 zeolite has the highest hydrogen storage capacity at 1.0 bar with 1.19 wt%, followed by H-MOR zeolite with 1.05 wt%, H–Y zeolite with 0.75 wt% and H-ZSM-12 zeolite with 0.60 wt%. The hydrogen adsorption data on FAU, MOR, MTW, and MWW at 77 K obey the Sips isotherm model. The experimental data show that the ultra-micropore volume of the zeolite is effective in hydrogen adsorption at low-pressure ranges. In addition, increasing the aluminum content of the zeolite increases the hydrogen adsorption capacity of the zeolite at atmospheric pressure. Therefore, zeolites with channel sizes close to the kinetic diameter of a hydrogen molecule, large cage volumes, and high aluminum content are potential candidates for energy storage applications. [Display omitted] • ZSM-12 and MCM-22 were synthesized and characterized. • The H 2 adsorption capacities of four zeolites were determined at 77 K and 1.0 bar. • The experimental data were analyzed using the Langmuir, Freundlich, and Sips isotherms. [ABSTRACT FROM AUTHOR]

Novel macrocycle co-crystals (MCCs) consisting of electron-rich phenanthrene[2]arene (P2) and electro-deficient 1,2,4,5-tetracyanobenzene (TCNB) have been prepared. The formed MCCs exhibited a specific selective vapochromic response to benzene among five aromatic hydrocarbon volatile organic compounds. Single-crystal structures and PXRD analyses confirmed that this specific selective vapochromic behavior was mainly attributed to the excellent benzene adsorption capacity of P2, leading to dissociation of P2@TCNB co-crystals and CT interactions which affect its optical features. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries have attracted significant attention in the realm of electronic energy storage and conversion owing to their remarkable theoretical energy density and cost‐effectiveness. However, Li–S batteries continue to face significant challenges, primarily the severe polysulfides shuttle effect and sluggish sulfur redox kinetics, which are inherent obstacles to their practical application. Metal‐organic frameworks (MOFs), known for their porous structure, high adsorption capacity, structural flexibility, and easy synthesis, have emerged as ideal materials for separator modification. Efficient polysulfides interception/conversion ability and rapid lithium‐ion conduction enabled by MOFs modified layers are demonstrated in Li–S batteries. In this perspective, the objective is to present an overview of recent advancements in utilizing pristine MOF materials as modification layers for separators in Li–S batteries. The mechanisms behind the enhanced electrochemical performance resulting from each design strategy are explained. The viewpoints and crucial challenges requiring resolution are also concluded for pristine MOFs separator in Li–S batteries. Moreover, some promising materials and concepts based on MOFs are proposed to enhance electrochemical performance and investigate polysulfides adsorption/conversion mechanisms. These efforts are expected to contribute to the future advancement of MOFs in advanced Li–S batteries. [ABSTRACT FROM AUTHOR]

In NH3 capture technologies, the desorption process is usually driven by high temperature and low pressure (such as 150–200 °C under vacuum), which accounts for intensive energy consumption and CO2 emission. Developing light responsive adsorbent is promising in this regard but remains a great challenge. Here, we for the first time designed and synthesized a light responsive azophenol‐containing covalent organic framework (COF), COF‐HNU38, to address this challenge. We found that at 25 °C and 1.0 bar, the cis ‐COF exhibited a NH3 uptake capacity of 7.7 mmol g−1 and a NH3/N2 selectivity of 158. In the adsorbed NH3, about 29.0 % could be removed by vis‐light irradiated cis‐trans isomerization at 25 °C, and the remaining NH3 might be released at 25 °C under vacuum. Almost no decrease in adsorption capacity was observed after eight adsorption‐desorption cycles. As such, an efficient NH3 capture and low energy release strategy was established thanks to the multiple hydrogen bond interactions (which are strong in total but weak in individuals) between NH3 and the smart COF, as well as the increased polarity and number of hydrogen bond sites after the trans‐cis isomerization. [ABSTRACT FROM AUTHOR]

In this work, two types of cationic lignin‐based adsorbents (AL‐METAC and AL‐GTA) were prepared through free radical polymerization or etherification reaction of alkali lignin with 2,3‐epoxypropyl‐3‐trimethylammonium chloride or methylacrylloxyethyl trimethyl ammonium chloride (METAC). The contents of quaternary ammonium groups in the adsorbents were adjusted by changing the dosages of 2,3‐epoxypropyl‐3‐trimethylammonium chloride and METAC to fabricate the adsorbents with excellent adsorption capacity. The structures, aqueous solubility, and physical properties of adsorbents were analyzed. Meanwhile, the effects of adsorbents dosage, pH value of solution, temperature, and ionic strength on the adsorption capacity of adsorbents were also analyzed. These two types of adsorbents exhibited outstanding affinity for phosphate, with a maximum removal efficiency of 51.8 and 73.2 mg/g, respectively. The adsorption processes followed pseudo‐second‐order and Langmuir models well. In addition, the AL‐GTA exhibited higher removal efficiency than AL‐METAC. Moreover, the AL‐METAC and AL‐GTA still retained 69.7% and 69.0% adsorption capacity after four times regeneration. The fabricated lignin‐based adsorbents have potential applications in the removal of phosphate from wastewater, which would promote the high‐value application of lignin. [ABSTRACT FROM AUTHOR]

Zeolites are widely used for removing volatile organic compounds (VOCs) in industrial processes. However, the understanding of the competitive adsorption behavior of multicomponent VOCs on zeolites remains insufficient. This study employed grand canonical Monte Carlo simulation to investigate the adsorption behaviors of nonpolar benzene and polar ethyl acetate in both pure and mixed forms on FAU, LTA and MFI zeolites. The effects of zeolite topology, Si/Al ratio, and compensating cations on competitive adsorption were explored. The results revealed that the adsorption capacities of benzene and ethyl acetate on FAU and LTA zeolites gradually increased with increasing Si/Al ratio, consistent with the increasing trends in their specific surface areas and pore volumes. However, the MFI zeolite shows no significant change in these properties with varying Si/Al ratios. Zeolites modified with Ca2+ significantly improved the benzene and ethyl acetate adsorption capacities, while impact on ethyl acetate adsorption is minimal. Zeolites modified with K+ reduced the adsorption capacities for both benzene and ethyl acetate. For binary mixtures, Na-FAU-1, Na-LTA-1, and Na-MFI-15 exhibited high selectivity for ethyl acetate. Increasing the Si/Al ratio and K+-modification reduced the adsorption selectivity of these zeolites for ethyl acetate. Ca2+-modification reduces the selectivity of LTA-1 toward ethyl acetate, with minimal impact on FAU-1 and MFI-15. Dynamic adsorption experiments with commercial zeolites confirm the reliability of the simulation results in predicting benzene and ethyl acetate adsorption performance. This study is expected to provide guidance for selecting appropriate zeolites for VOCs mixtures in practical applications. [ABSTRACT FROM AUTHOR]

Ammonia becomes one of the indispensable raw materials in production and life, with the continuous development of industry. Ammonia pollution of the environment is becoming more and more serious, so the adsorption of ammonia is essential. In this paper, a new biochar material based on tannic acid was developed. The tannic acid was self-polymerized using different activators (K2CO3, KHCO3, KOH). Tannic acid biochar (TAB-X) was obtained by pyrolytic carbonization reaction at 800 ℃. The biochar was treated with phosphoric acid 10% by mass (TAB-X-10%PO4), and unlike other biochar materials, the specific surface area and hydroxyl content were increased after acidification, but there were no acidic functional groups. It is noteworthy that the specific surface area of TAB-KOH increased from 22 m2/g to 667 m2/g after acidification. The adsorption capacity of ammonia vapor reached 342.6 mg/g. It is proposed that the adsorption mechanism is an adsorption process in which hydroxyl groups on the surface of TAB-X firstly adsorb water, and after that ammonia gas is then dissolved in the water molecules on the surface of the biochar. These results highlight the great potential of TAB as an adsorbent for the adsorption of ammonia, in addition to the low price of raw materials and the simple preparation conditions of this preparation process, which corresponds with the conditions for mass production as well as practical application. [ABSTRACT FROM AUTHOR]

The development of metal–organic frameworks for carbon dioxide (CO2) capture has drawn considerable interest among researchers with MIL-101(Cr) gaining significance owing to its high stability. This paper investigates the one-step synthesis of MIL-101-NH2(Cr) by using guanidine hydrochloride as a mediator under relatively mild conditions (aqueous phase, reaction temperature of 120 °C, and without the use of mineralization agents such as hydrofluoric acid). MIL-101-NH2(Cr) not only exhibited a high specific surface area with a Lewis-base site-rich ligand but also possessed a good CO2 adsorption capacity of 3.96 mmol/g at 1 bar. Furthermore, diethylenetriamine (DETA) was loaded into MIL-101-NH2(Cr) to design a new CO2 adsorbent DETA@MIL-101-NH2(Cr). The loaded material maintained the original structure and also displayed an improved adsorption capacity of 0.29 mmol/g under low (< 0.11 bar) CO2 partial pressure. The absorbents possessed good selectivity, stability, and recyclability which make them ideal candidates for CO2 capture. [ABSTRACT FROM AUTHOR]

A super-lightweight, bidirectionally ordered, three-dimensional porous hybrid graphene aerogel (HGA) was prepared and evaluated. The preparing parameters involved obtaining a uniform suspension through mechanical stirring for 3 h, followed by ultrasonic dispersion for 30 min, maintaining pH at 9. The suspension then underwent liquid nitrogen pre-freezing, vacuum freeze-drying for 48 h and hydrazine hydrate vapor reduction at 90 ℃ for 24 h. Furthermore, the microstructure, the adsorption and reusability properties of HGA were evaluated. The results demonstrated that HGA could adsorb organic solvents up to 159 times its own weight and effectively separate oil from water. The HGA exhibited excellent mechanical properties, releasing 98% of its shape with a 30% compression ratio under a stress 2653 times its own weight. Additionally, after 10 adsorption-combustion cycles, the adsorption capacity decreased by only 3.67%, and the mass retention rate exceeded 90%, indicating good reusability and flame-retardant properties. [ABSTRACT FROM AUTHOR]

This research developed a novel composite of MOF-NH2 and graphene oxide (GO) for enhanced CO2 capture. Employing the response surface methodology-central composite design (RSM-CCD) for experiments design, various MOF-NH2/GO samples with GO loadings from 0 to 30 wt% were synthesized. The results of SEM, XRD, EDS, and BET analysis revealed that the materials maintained their MOF crystal structure, confirmed by X-ray diffraction, and exhibited unique texture, high porosity, and oxygen-enriched surface chemistry. The influence of temperature (25–65 °C) and pressure (1–9 bar) on CO2 adsorption capacity was assessed using a volumetric adsorption system. Optimum conditions were obtained at weight percent of 22.6 wt% GO, temperature of 25 °C, and pressure of 9 bar with maximum adsorption capacity of 303.61 mg/g. The incorporation of amino groups enhanced the CO2 adsorption capacity. Isotherm and kinetic analyses indicated that Freundlich and Fractional-order models best described CO2 adsorption behavior. Thermodynamic analysis showed the process was exothermic, spontaneous, and physical, with enthalpy changes of − 16.905 kJ/mol, entropy changes of − 0.030 kJ/mol K, and Gibs changes energy of − 7.904 kJ/mol. Mass transfer diffusion coefficients increased with higher GO loadings. Regenerability tests demonstrated high performance and resilience, with only a 5.79% decrease in efficiency after fifteen cycles. These findings suggest significant potential for these composites in CO2 capture technologies. [ABSTRACT FROM AUTHOR]

Enhancing the accessibility and utilization of active sites through mesopores in carbon anode materials is crucial for developing high‐power potassium‐ion hybrid supercapacitors (PIHCs). Here, a multiscale phase separation method combining block copolymer (BCP) microphase‐ and homopolymer (HP) macrophase‐separation is utilized to produce two model carbon materials with controlled mesopore orientation: open‐end (oe‐MCS) and closed‐end mesoporous carbon sphere (ce‐MCS). BCPs form identical cylindrical micelles, and HPs encapsulate these cylindrical micelles within spheres and control their orientations relative to the interface. This approach manipulates only the degree of mesopore openings in the MCS materials while maintaining all other factors at similar levels. Opening mesopores in carbon anode materials primarily enhances K+ adsorption capacity, reduces K+ diffusion length, and improves ion transport. Thus, oe‐MCS anode exhibits a higher specific capacity with a significant capacitive‐controlled contribution. The resulting PIHC device displays maximum energy and power densities of 103 Wh kg−1 and 12 300 W kg−1, respectively, along with capacity retention of 86.1% after 20 000 cycles at 2.0 A g−1. This study significantly advances the understanding of mesopore design to improve capacitive K+ storage in hard carbon materials, paving the way for the development of high‐power PIHCs. [ABSTRACT FROM AUTHOR]

The massive emission of carbon dioxide produces the greenhouse effect and poses a threat to the survival of modern civilization. The search for new carbon management strategies has been at the forefront of scientific research over the past few decades. Integrated carbon dioxide capture and utilization (ICCU), which aims to capture CO2 and convert it in situ into high value‐added products or fuels, is considered to be more attractive and innovative than alternative strategies. This paper introduces the adsorption capacity and characteristics of solid sorbents at different operating temperatures. On this basis, the recent research on ICCU technology combined with methanation, reverse water−gas shift reaction, dry reforming of alkanes and dehydrogenation of alkanes over novel dual‐function materials is presented, and the development direction and future prospects of ICCU are discussed. [ABSTRACT FROM AUTHOR]

Aerogels with ultrahigh porosity and large specific surface area have demonstrated great potential for capturing volatile organic compounds (VOCs). Especially, aerogel fiber aggregates with macropores formed by overlapping aerogel fibers and mesopores in the aerogel fibers might realize fast sorption kinetics and high sorption capacity simultaneously. However, how to develop fast fabrication and large‐scale production of aerogel fibers remains a challenge. Herein, a generic sol‐gel centrifugal spinning (SCS) strategy with a spinning rate capable of reaching 700 m min−1 is developed for producing aerogel fibers. The representative SCS aerogel fiber made from aramid nanofiber (ANF) dispersion exhibits a large specific surface area (313 m2 g−1) and high tensile strength (12.48 MPa). The SCS strategy is further applied to fabricate various kinds of aerogel fibers, including sodium alginate, cellulose, and chitosan. The ANF aerogel fiber aggregates exhibit superior VOC adsorption capacity of 438.0 mg g−1 under an ultrafast gas flux of 3.8 × 104 L m−2 h−1, which also has satisfactory cyclic stability. This work not only develops a powerful and generic strategy for fabricating aerogel fibers in large scale, but also provides inspiration for applying these SCS aerogel fibers in dynamic removal of VOCs and other environmental protection fields. [ABSTRACT FROM AUTHOR]

In the current research, the efficiency of the synthesized activated carbon/alginate/Fe3O4 composite adsorbent for the removal of Pb (II) ions from aqueous media was investigated. SEM, Energy Dispersive X-Ray Analysis (EDX)/Map, FTIR, XRD, BET, and Vibrating-Sample Magnetometer (VSM) analyses were used to characterize the synthesized adsorbent. The optimal values of adsorption operating parameters including solution pH (6), temperature (50 °C), dosage of adsorbent (1.5 g/L), Pb (II) ion initial concentration (10 mg/L), and contact time (80 min) were determined through batch experiments. According to the outcomes of the experiments, the utmost value for the adsorption efficiency was equal to 97.83% which was attained in the above-mentioned optimal conditions. Based on the equilibrium study results, Freundlich isotherm model (R2 > 0.9952) described the equilibrium of the current process better than Langmuir model, which demonstrated that the adsorption of lead ions was occurred on a heterogeneous surface. It should be noted that the maximum adsorption capacity of the adsorbent was 37.764 mg/g. In addition, the kinetics of the process was defined well by the pseudo-second order kinetic model (R2 > 0.99). The process was also endothermic (∆H < 0) and spontaneous (∆G < 0), while the random collisions on the solid/liquid interface increased since ∆S was positive. Moreover, regeneration experiments indicated that the current adsorbent showed to have the capability of adsorption/desorption for 6 consecutive cycles. [ABSTRACT FROM AUTHOR]

Rubidium (Rb), a rare and precious metal, is widely used in high‐tech fields. In this work the structural advantages of mordenite (MOR) and group affinity of phenolic hydroxyl polymers (poly (styrene‐4‐hydroxystyrene) (P(S‐co‐VPh)) are combined to prepare MOR/P(S‐co‐VPh) nanofiber composite membranes with high selectivity and adsorption specificity for Rb+ by electrospinning. The test results show that MOR is successfully anchored on the nanofiber substrate and maintained its complete crystal structure. Adsorption experiments show that the adsorption capacity of Rb+ increases with the increase of MOR content, and pH = 9.0, T = 25°C are the best adsorption conditions. K+ shows the most obvious interference with the adsorption capacity decreased from 60.03 to 39.33 mg/g. The adsorption process follows with the Langmuir isothermal model and pseudo‐second‐order kinetic equation. The chemical adsorption based on the coordination reaction is the control step, and the intraparticle diffusion also has an important effect on the adsorption rate. The recycling test indicates that the prepared nanofiber composite membrane not only has efficient adsorption of Rb+, but also exhibits excellent regeneration and stability, which helps to achieve its widespread application and long‐term operation in harsh environments. [ABSTRACT FROM AUTHOR]

A sustainable strategy based on chitin from waste seafood is proposed to remove nano‐size microplastics in water. A chitin nanofibrous foam is constructed by a new hydrogen bond rearrangement scheme without any crosslinking, which delivers an impressive high adsorption capacity of 411.14 ± 1.50 mg g−1 for small‐sized (< 1 µm) microplastics. This excellent adsorption capacity stems from the rough fibrous surface structure of the highly porous foam, the positively charged nature of the partially deacetylated chitin and other molecular interactions introduced by the activation and increased exposure of ‐OH, ‐NH2 and ‐NHCO‐ groups. Molecular dynamics simulation further demonstrates that C‐H‐π, O‐H‐π, and C = O‐π interactions between the microplastics and chitin foam facilitates the efficient removal of microplastics. A high removal efficiency is maintained even in salty water, a property that exemplifies good adaptability to various water bodies. Finally, two proof‐of‐principle scenarios are presented for converting the recovered microplastics into value‐added products. Thus, the entire cycling strategy represents a powerful remedy for the urgent yet challenging ocean microplastic pollution problem. [ABSTRACT FROM AUTHOR]

In this study, a selective sorbent was fabricated by combining a surface molecularly‐imprinted polymer and magnetic kaolin for reliable quantification of thiabendazole (TBZ) coupled with spectrofluorimetry. Several surface characterization methods were conducted to confirm the synthesis of TBZ‐imprinted magnetic kaolin with a polymer thickness of ~48 nm. The molecularly‐imprinted magnetic kaolin (MIP@MKLN) showed high adsorption capacity (8.7 mg/g), remarkable selectivity with an imprinting factor of 3.71 and excellent regeneration ability for up to 10 uses without significant change of its initial adsorption capacity for TBZ. The proposed method had linear range from 5 to 500 μg/mL TBZ concentration with a correlation coefficient of 0.995 and the limit of detection was 1.4 μg/mL. MIP@MKLN was used for selective separation and quantification of TBZ in orange and lemon samples. There were high recovery values ranging from 96.4% to 100.2% with lower relative standard deviations (less than 5%) in the spiked samples under optimized conditions. Overall, the proposed method based on MIP@MKLN as an excellent sorbent could produce a feasible, convenient, and promising method for rapid, selective, and sensitive quantification of TBZ in real samples. [ABSTRACT FROM AUTHOR]

The advancement of Zn–Se batteries has been hindered by significant challenges, such as the sluggish kinetics of Se cathodes, limited Se loading, and uncontrollable formation of Zn dendrites. In this study, a bidirectional optimization strategy is devised for both cathode and anode to bolster the performance of Zn–Se batteries. A novel bowl‐in‐ball structured carbon (BIBCs) material is synthesized to serve as a nanoreactor, in which tin‐based materials are grown and derived in situ to construct cathodes and anodes. Within the cathode, the multifunctional host material (SnSe@BIBCs) exhibits large adsorption capacity for selenium, and demonstrates supreme catalytic properties and spatially confined characteristics toward the selenium reduction reaction (SeRR). On the anode, Sn@BIBCs displays triple‐induced properties, including the zincophilic of the internal metallic Sn, the homogenized spatial electric field from the 3D spatial structure, and the curvature effect of the bowl‐shaped carbon. Collectively, these factors induce preferential nucleation of Zn, ensuring its uniform deposition. As a result, the integrated Zn–Se battery system achieves a remarkable specific capacity of up to 603 mAh g−1 and an impressive energy density of 581 W kg−1, highlighting its tremendous potential for practical applications. [ABSTRACT FROM AUTHOR]

Nanostructured porous materials are desirable sorbents for separating and removing oil spills from water. This work examines the performance of the prepared efficient sorbents in the oil sorption process. Polyacrylonitrile (PAN) fibers served as the skeleton matrix, while glutaraldehyde and poly(vinyl alcohol) (PVA) served as cross-linking agents. The prepared polymer sorbents showed high adsorption capacity (12.47 g/g), porosity (95.41%) and low density (0.069 g/cm3). The incorporation of carbon nanostructures (nanotubes or graphene oxide) in the sorbent increased the adsorption capacity to 14.85 g/g. The hydrophobic nature of carbon nanotubes significantly increases the contact angle of water with the surface of the nanocomposite absorber and reaches 137.5 degrees. The obtained sorbents showed good reusability in the adsorption process and maintained an adsorption capacity of about 10 g/g after 5 cycles. The optimal temperature range for using nanocomposite sorbents was 25°C to 35°C. The combination of high sorption capacity, low porosity and density in modified polyacrylonitrile, along with its reusability, makes this designed sorbent highly suitable for efficient removal of oil spills. [ABSTRACT FROM AUTHOR]

Direct air carbon capture (DAC) is vital to achieving negative CO2 emissions, with physical adsorption offering a cost‐effective and energy‐efficient solution. an advanced zeolite modification technique is presented using cold plasma, which enhances the CO2 adsorption efficiency of NaX zeolite by 11.5% after just 60 min. This method utilizes the electric field to reorganize cation distribution and pore structure and significantly improve the adsorption capacity, efficiency, and selectivity. Compared to traditional methods, this technique is simpler and more effective, as demonstrated through first‐principles calculations, thermodynamics, kinetics, and adsorption equilibrium studies. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA) is an endocrine disruptor and poses serious threats to human health, and widespread concern has been raised regarding its effective removal from the environment. In this work, an eco-friendly surface molecularly imprinted composite (MIL-100(Fe)@MIP) was successfully fabricated in the green solvent of water and further achieved the fast and effective removal of BPA. The maximum adsorption capacity of BPA bound to MIL-100(Fe)@MIP was 15.45 mg g−1, and the adsorption behavior was adequately described with the Langmuir model. MIL-100(Fe)@MIP acquired fast adsorption of BPA, and the equilibrium adsorption capacity achieved 95% within 10 min. The adsorption process better matches the pseudo-second-order model. As a solid phase sorbent, MIL-100(Fe)@MIP was successfully applied to rapidly and efficiently remove BPA from five real samples, which included disposable food containers, canned yellow peach, orange juice, soybean milk and teabags, and the recoveries ranged from 80.67% to 100.58%. Furthermore, MIL-100(Fe)@MIP exhibited excellent reusability for 20 cycles. Hence, the developed MIL-100(Fe)@MIP is an eco-friendly and promising adsorbent that can effectively and rapidly remove BPA from the environment. [ABSTRACT FROM AUTHOR]

The extensive use of sulfonamide antibiotics (SAs) proved to be harmful to humans and the environment; thus, the treatment of SAs in water is imminent. In this work, mesoporous SBA-15 silicon was modified using N-[3-(trimethoxysilyl)propyl]ethylenediamine (AAPTMS) through the formation of AAPTMS-SBA-15. The adsorption performance of AAPTMS-SBA-15 toward sulfamethizole (SIZ) was investigated in the absence and presence of various metal ions, and the results reveal that the introduction of Ni2+ substantially improved the adsorption capacity for SIZ. To maximize the adsorption performance toward SIZ, AAPTMS-SBA-15 was then combined with the heavy metal Ni2+ to prepare Ni-AAPTMS-SBA-15. Subsequently, the adsorption performance and behavior of Ni-AAPTMS-SBA-15 were studied in terms of pH, adsorbent dosage, kinetics, isothermal adsorption, and thermodynamics. SIZ exhibited spontaneous and exothermic adsorption on Ni-AAPTMS-SBA-15, which rapidly reached equilibrium within 2 min; the maximum adsorption capacity was 188.68 mg g−1 at pH = 5.0 and adsorbent dosage of 8 mg. The effective adsorption of SIZ was attributed to the combined mechanisms of electrostatic interaction, complexation and pore-filling. [ABSTRACT FROM AUTHOR]

As one of the most potent greenhouse gases, SF6 has a significant economic and environmental impact on the purification and recovery of exhaust gases from the semiconductor industry. The adsorption and separation performance of SF6 on a two‐dimensional covalent organic framework TAT‐COFs‐1‐AB with different functional groups (SO3H, Et, NH2, OMe, OH, H) was investigated by using grand canonical Monte Carlo (GCMC) simulations and density functional theory (DFT) calculations. The results show that the adsorption at low pressure depends on the interactions between the SF6 and COF frameworks, while at high pressure it is mainly affected by the porosity. The highest adsorption capacity of 8.44 mmol/g (298 K, 100 kPa) is exhibited by TAT‐COF‐1‐AB‐H, which has the highest porosity. Chemical functionalization was found to be effective in enhancing the SF6/N2 selectivity. Among all the functionalized COFs, TAT‐COF‐1‐AB‐NH2, with the highest specific surface area and strong heat of adsorption, showed the highest selectivity. The simulation of self‐diffusion also shows consistent results with the GCMC simulation. The findings highlight that the adsorption capacity is influenced by substituent and porosity, with SF6 showing a consistent preference for adsorption at hollow sites, as evidenced by binding energy and charge transfer analyses. [ABSTRACT FROM AUTHOR]

This study is concerned with the physicochemical investigation of cobalt (II) sorptions from aqueous solution by potato peel (PP) and NaOH/CaCl2/C2H5OH‐modified potato peel (MPP). The sorption conditions of PP and MPP under optimized conditions were optimized according to the maximum effects of the main factors affecting the sorption processes (PP and MPP dosage, sorbate concentration, interaction time, and temperature) at pH 6.78. The kinetic and equilibrium experimental sorption data of the studied sorbates were simulated using commonly used models and were found to fit well with pseudo‐second‐order and Langmuir models. The Co(II) ion adsorption capacity of PP was determined as 12.25, 16.44, and 20.74 mg/g, respectively, at various temperatures (25, 35, and 45 °C), while the adsorption capacity of MPP under the same conditions was determined as 41.49, 52.35, and 62.50 mg/g. Thermodynamic parameters determined for each sorption system showed that the sorption processes were endothermic and spontaneous. The results of this study emphasize that both PP and MPP can be used as effective sorbents for removing pollutants from water. [ABSTRACT FROM AUTHOR]

Heterostructures comprising NiCoP and NiCo 2 S 4 (referred to as NCP/NCS) were created by incorporating P and S elements into NiCo 2 O 4 (NCO) micro-nanospheres through phosphorization and hydrothermal sulfurization processes. Selective construction of heterogeneous structures can balance the advantages and disadvantages of each single component and is desirable in HER applications. In alkaline media, the resulting product NCP/NCS had an overpotential of 195 mV at a current density of 10 mA cm−2, which is 337 mV higher than that of the original NCO and significantly better than the products of pure phosphide (NCP) and sulfide (NCS). Its Tafel slope was about 83 mV dec−1 and the HER performance did not decay significantly over 48 h. On the other hand, the formation of heterogeneous interfaces improves the intrinsic catalytic activity of the materials. Density functional theory (DFT) simulations show that the hydrogen adsorption capacity at the heterogeneous interface is optimized due to charge enrichment, which in turn enhances the intrinsic activity. • Micro-nanospheres heterostructures was prepared via gas-liquid diffusion method. • Morphology characterization displays the obvious interface and crystalline surface. • The heterostructures delivers a low overpotential than that of single component. • Density functional theory reveals the heterogeneous interface enhance hydrogen adsorption. [ABSTRACT FROM AUTHOR]

Different dyes are discharged into water streams, causing significant pollution to the entire ecosystem. The present work deals with the removal of acid red 2 dye (methyl red—as an anionic dye) by green sorbents based on chitosan derivatization. In this regard, two classes of chitosan derivatives—a total of six—were prepared by gamma irradiation at 30 kGy. The first group (group A) constitutes a crosslinked chitosan/polyacrylamide/aluminum oxide with different feed ratios, while the second group, identified as group B, is composed of crosslinked carboxymethyl chitosan/polyacrylamide/aluminum oxide with different ratios. Glycerol was added to soften the resultant hydrogels. The products were characterized by different tools, including FTIR for confirming the chemical modification, TGA for investigating their thermal properties, and XRD for verifying their crystalline structure. The morphology of the prepared derivatives was studied through SEM, while their topography before and after dye adsorption was monitored via the AFM. The removal efficiencies of the prepared sorbents were verified at different operation conditions, such as pH, temperature, adsorbent dose, initial concentration of dye solutions, and contact time. The data revealed that the optimum conditions for maximum dye uptake were as follows: pH 4, contact time 120 min, 0.1-g sorbent dose, and 50-ppm dye concentration. Additionally, the prepared sorbents demonstrated potent adsorption capacity and removal efficiency. It was found that the elements of the second group displayed higher performance than their counterparts. The data showed also that the adsorption process best fits with the Freundlich model and obeyed pseudo-first-order kinetic isotherm. In addition, the synthesized composites showed observable antibacterial potency toward E. coli as a Gram-negative bacterium and S. aureus as a Gram-positive bacterium. [ABSTRACT FROM AUTHOR]

Magnetic solid phase adsorption separation (MSPA) technology is an efficient and convenient separation method, which can simplify the separation step and shorten the separation time. It has wide application value in the purification of antibiotic pollutants in water. In this study, a novel magnetic biochar adsorbent (DES1@MnFe2O4‐BBC) with strong selectivity and high adsorption capacity was synthesized. It was composed of banana peel as the biochar source, Mn/Fe bimetallic oxide as the magnetic source and deep eutectic solvent (DES) as the functional monomer. The physicochemical properties of DES1@MnFe2O4‐BBC were systematically characterized by nitrogen adsorption–desorption, synchronous thermal analyzer, vibrating sample magnetometer, X‐ray diffractometer, X‐ray photoelectron spectroscopy, and field emission electron microscopy. The adsorption conditions were optimized by the single‐factor optimization method. Also, under the optimal adsorption conditions, the maximum adsorption capacity of DES1@MnFe2O4‐BBC for ceftiofur sodium was 75.01 mg·g−1. The test of adsorption thermodynamics and kinetics illustrated that the Langmuir isotherm adsorption model and pseudo‐second‐order kinetic equation were suitable well with the adsorption system established in this article. Adsorbent regeneration cycle experiment revealed that the DES1@MnFe2O4‐BBC was an efficient and reusable adsorbent. In the end, all research proves the novel magnetic adsorbent synthesized in this study can provide a new idea for the removal of antibiotics in water. [ABSTRACT FROM AUTHOR]

CO2 capture and storage have been regarded as promising concepts to reduce anthropogenic CO2 emissions. However, the high cost, inferior adsorption capacity, and higher effective activation temperature of traditional sorbents limit their practical application in efficient CO2 capture. Here, a C‐S‐H@ZIF‐8 (C‐S‐Z) sorbent is fabricated by in situ growth of the ZIF‐8 shell on the C‐S‐H (calcium‐silicate‐hydrate) surface for ultra‐high CO2 adsorption and storage. Among the C‐S‐Z, the outer ZIF‐8 shell acts as a transport channel that promotes CO2 absorption toward the underlying C‐S‐H substrate for accelerated carbonation while preventing nitrogen and water from reaching the interior C‐S‐H. As a consequence, C‐S‐Z possesses the merits of ample pyrrolic nitrogen, porous structure, and ultra‐high surface area (577.18 m2 g−1), that contribute to an ultra‐high CO2 capture capacity, reaching 293.6 mg g−1. DFT calculations show a high CO2 adsorption energy and the mineral carbonation is dominant by the adsorption process. In particular, the advantages of the outstanding adsorption capacity, low cost, and high CO2 selectivity make this C‐S‐H‐based sorbent hold great potential in the practical application for direct air CO2 capture and storage. [ABSTRACT FROM AUTHOR]

In this paper, the bimetallic metal–organic frameworks (MOFs) of FeNi-BDC and FeNi-BDC-NH2 (BDC, 1,4-benzenedicarboxylate) with similar Fe/Ni molar ratio, crystal structure, porosity and thermal stability were synthesized by a solvothermal method. The results of adsorption experiments at ambient conditions showed that the adsorptive uptake of NO, CO2, O2 and N2 on FeNi-BDC were all very small under different adsorption partial pressures, with FeNi-BDC displaying a weak adsorption property because of its lack of unsaturated adsorption sites. On the contrary, at 100 kPa, the adsorption of NO by FeNi-BDC-NH2 was considerably higher than that by FeNi-BDC, indicating that the incorporation of NH2 on the ligand could effectively enhance the adsorption of NO. The adsorption capacity of FeNi-BDC-NH2 for NO reached 142.17 cm3 g−1, which was considerably higher than its capacity for CO2, O2 and N2 under the same conditions. Ideal Adsorption Solution Theory simulations calculated the adsorption selectivity for NO/CO2 and NO/O2 under a mixed atmosphere to reach 1325 and 13,346 respectively, demonstrating high adsorption selectivity. Through in situ infrared experiments and calculations of the enthalpy of adsorption, it was demonstrated that FeNi-BDC-NH2 adsorbed NO because NO can combine with NH2 in the material to form a NONOate structure. A preliminarily exploration of the mechanism of NO adsorption and the influence of NH2 functional groups on the adsorption and separation of NO revealed that the selectivity of adsorption was closely related to the variability of the enthalpy of adsorption. This also provided a new strategy for the adsorption and separation of NO in the flue gas environment. The bimetallic metal–organic frameworks of FeNi-BDC and FeNi-BDC-NH2 (BDC, 1,4-benzenedicarboxylate) with similar Fe/Ni molar ratio, crystal structure, porosity and thermal stability were synthesized by a solvothermal method. FeNi-BDC-NH2 demonstrated superior NO adsorption performance and high adsorption selectivity, indicating that the introduction of NH2 on the ligand can improve the adsorption capacity and selectivity of the material for NO, which also provides a new strategy for adsorption and separation of NO in a flue gas environment. (Image credit: Li Hao.) [ABSTRACT FROM AUTHOR]

A novel magnetic dispersive solid phase extraction (MDSPE) procedure based on the deep eutectic solvent (DES) modified magnetic graphene oxide/metal organic frameworks nanocomposites (MGO@ZIF-8@DES) was established and used for the efficient enrichment of estradiol, estrone, and diethylstilbestrol in cosmetics (toner, lotion, and cream) for the first time. Then, the three estrogens were separated and determined by UHPLC-UV analysis method. In order to study the features and morphology of the synthesized adsorbents, various techniques such as FT-IR, SEM, and VSM measurements were executed. The MGO@ZIF-8@DES nanocomposites combine the advantages of high adsorption capacity, adequate stability in aqueous solution, and convenient separation from the sample solution. To achieve high extraction recoveries, the Box-Behnken design and single factor experiment were applied in the experimental design. Under the optimum conditions, the method detection limits for three estrogens were 20–30 ng g−1. This approach showed a good correlation coefficient (r more than 0.9998) and reasonable linearity in the range 70–10000 ng g−1. The relative standard deviations for intra-day and inter-day were beneath 7.5% and 8.9%, respectively. The developed MDSPE-UHPLC-UV method was successfully used to determine three estrogens in cosmetics, and acceptable recoveries in the intervals of 83.5–95.9% were obtained. Finally, three estrogens were not detected in some cosmetic samples. In addition, the Complex GAPI tool was used to evaluate the greenness of the developed pretreatment method. The developed MDSPE-UHPLC-UV method is sensitive, accurate, rapid, and eco-friendly, which provides a promising strategy for determining hormones in different complex samples. [ABSTRACT FROM AUTHOR]

This study represents a comprehensive assessment of methane adsorption capacity and pore characteristics for the coal seams of the Soma Basin in Western Türkiye, with a focus on their implications for coalbed methane potential. Twenty-one exploration wells were utilized to obtain coal samples from the kP1 and kM2 coal seams in the Kınık coalfield of the Soma Basin. High-pressure methane adsorption experiments using the indirect gravimetric method were conducted to quantify the storage capacities of these coal seams. Results revealed a wide range of methane adsorption capacities, ranging from 10.5 to 28.3 m3/t (air-dry basis), indicating significant methane storage potential for the kP1 and kM2 coal seams. The gas contents, ranging from 1.1 to 4.3 m3/t (as-received basis), suggested that the coal seams were undersaturated. Low-pressure N2/CO2 adsorption tests, along with standard proximate and gross calorific value analyses, were performed to investigate the influence of coal quality and pore characteristics on methane adsorption capacities. The findings demonstrated correlations between coal quality parameters and adsorption capacity, with ash yield showing a moderately negative correlation and fixed carbon content and gross calorific values exhibiting moderately positive correlations. Microporosity was identified as the critical factor governing methane adsorption, with a strong positive correlation observed between micropore surface areas and volumes and adsorption capacity. These results highlight the significant methane storage capacities of the coal seams in the Soma Basin and underscore the importance of micropores in determining methane adsorption capacity. The findings provide valuable insights for optimizing methane extraction and utilization in the region and offer important considerations for reservoir characterization and development strategies in similar low-rank coal deposits. Highlights: Extensive evaluation of methane adsorption and pore characteristics in Soma Basin coals, uncovering substantial potential for coalbed methane. The study reveals a diverse range of methane adsorption capacities, indicating highly promising methane storage capabilities. Correlation between coal quality parameters and methane adsorption, offering valuable insights into gas storage influenced by coal composition. Emphasis on the crucial role of micropores in methane storage, underscoring their significance as primary adsorption sites. Practical implications for optimizing methane extraction and utilization, guiding reservoir development in low-rank coal deposits like Soma Basin. [ABSTRACT FROM AUTHOR]

Pore volume, pore size and adsorption capacity are fundamental factors that control gas storage and production in shale reservoirs. We investigated the evolution of pore structure and adsorption capacity as functions of lithology and present-day burial depth. Nineteen shale samples from the Wufeng-Longmaxi Formation from shallow depths (present depths < 700 m) in the Sichuan Basin, China, were analyzed to elucidate the evolution of the pore system, applying N2/CO2 isotherm adsorption, high-resolution FE-SEM, FIB-SEM, and CH4 isotherm adsorption. Two comparison basin models with 700 m and 4000 m present-day burial depth were constructed to illustrate the impact of uplift on pore structure and methane adsorption. The results indicate that mineral structure, rock fabric, and TOC content are essential factors affecting the pore structure. Pores of various sizes are preserved through different mechanisms during the compaction. The development of micropores is mainly controlled by thermal maturity and TOC content. In contrast, mesopores and macropores are stress-sensitive and prone to be compacted during deposition. Methane adsorption capacity is highly related to the burial depth. During the process of reservoir uplift, the methane adsorption capacity of the reservoir gradually increases with decreasing burial depth, with a transition point occurring between 700 and 1300 m. Furthermore, as the reservoir continues to uplift to burial depths below 700 m, the methane adsorption capacity of the reservoir in normally pressured shale gas formations rapidly decreases. However, for overpressured shale gas reservoirs, there is no significant change in the methane adsorption capacity of the reservoir. Highlights: Mechanism of pore structure development during subsidence and uplift was analyzed, and the pores with different sizes were also taken into consideration. The effect of burial depth and uplift in terms of pressure and temperature on pore gas storage capacity was analyzed, and three stages of shallow shale gas adsorption were reconstructed. An empirical formula was proposed for considering methane adsorption in ultra-shallow shale reservoirs. Both over pressured and hydrostatic pressure condition was considered in our models. [ABSTRACT FROM AUTHOR]

This study explored the fabrication of Polypyrrole (PPy) and Granular Activated Carbon (GAC) composites (PPy‐GAC) for effective removal of toxic hexavalent chromium (Cr(VI)) from aqueous solutions. Two synthesis methods are employed: (1) electrostatic deposition of PPy onto pre‐charged GAC paper and (2) in‐situ chemical polymerization of pyrrole monomer with GAC particles. Batch adsorption experiments investigated the impact of various operational parameters on Cr(VI) removal. Compared to pristine GAC (54.64 mg g−1), the PPy‐GAC composite exhibited a remarkable 3‐fold increase in equilibrium adsorption capacity, reaching 175.44 mg g−1. Pseudo‐second‐order kinetic model (R2 > 0.999) accurately described the adsorption kinetics, while the Langmuir isotherm model (R2 > 0.99) provided a good fit for the equilibrium data. Maximum adsorption capacity (qmax) increased with temperature, reaching 204.08, 243.90, and 270.27 mg g−1 at 298, 308, and 318 K, respectively. Furthermore, a fixed‐bed column experiment examined the composite's effectiveness in continuous Cr(VI) removal, demonstrating its suitability for practical applications. Notably, the PPy‐GAC composite successfully removed Cr(VI) from a real wastewater sample containing 68 µg L−1 Cr(VI) obtained from a ferrochrome industry, highlighting its potential for real‐world remediation. [ABSTRACT FROM AUTHOR]

The purification of flavonoids using the macroporous polymer resin method has gained attention in recent years due to its simplicity, precision, cost‐effectiveness, and the ability to separate flavonoids from other constituents. Several studies have been conducted to investigate the efficiency and effectiveness of macroporous polymer resin in purifying flavonoids from various plant sources. This review aims to evaluate the existing literature on macroporous polymer resin purification of flavonoids and provide a comprehensive analysis of the current research trends and advancements in this field. It also highlights the importance of optimizing the adsorption parameters and conditions such as resin type, resin concentration, pH, and temperature for efficient purification of flavonoids using macroporous polymer resin. The key findings of this review reveal that macroporous resins with weak polarity, large surface areas, and pore diameters have a stronger adsorption capacity for flavonoids compared to polar resins. Furthermore, ultrasonic‐solvent assisted extraction often combines with macroporous resin for effective the extraction and purification of flavonoids. [ABSTRACT FROM AUTHOR]

For industrial tail gas to be converted into high-purity hydrogen, the H2-N2 mixture needs to be separated efficiently. This work examined the adsorption characteristics and competitive mechanisms of H2 and N2 on LTA- and FAU-type zeolites, at 77 K, 298 K, and 0.1–10 bar by thoroughly analyzing results of adsorption capacity experiments and molecular simulations. In the Grand Canonical Monte Carlo (GCMC) simulations, the force field causing a molecular dipole of H2 and the polarization force field of N2 are first applied. The accuracy of the force field was experimentally verified. The findings indicate that N2 and H2 loading on Ca-FAU (Ca-LTA) are higher than Na-FAU (Na-LTA). On NaX at 77 K, the highest adsorption selectivity (N2/H2) is observed; on NaA at 298 K, it is the opposite. The GCMC data findings demonstrate that H2 and N2 have remarkably similar adsorption sites, with framework oxygen atoms and non-framework cations serving as the main adsorption sites for adsorbate molecules. Furthermore, the rate at which H2 diffuses is higher than that of N2. The study of redistribution charge before and after adsorption demonstrated that N2 has a greater affinity for the framework oxygen atoms than H2. This study provides a molecular theoretical foundation for the adsorption behavior of H2-N2 mixture in zeolites. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the efficacy of biochar, produced from different agricultural residues varying in lignin and cellulose content and subjected to different pyrolysis temperatures, in removing cadmium ions (Cd (II)) from an aqueous solution. This removal process is crucial for protecting human health and the environment. Specifically, the study focused on the adsorption behaviors of Cd (II) by the biochars made from rice husk biochar (RHB), maize straw biochar (MSB), peanut shell biochar (PSB), cottonseed shell biochar (CHB), and mulberry leaf biochar (MLB), which were prepared at 300 °C and 600 °C. The results indicated that the type of agricultural residue used to produce biochar significantly influenced the adsorption of Cd (II). Notably, mulberry leaf biochar prepared at 300 °C (MLB-300) demonstrated the highest adsorption efficiency, achieving a maximum adsorption capacity of 42.2 mg g−1. Batch adsorption experiments assessed the impact of various factors, including system pH, NO3− concentration, and adsorption duration. The adsorption kinetics were better described by the pseudo-second-order model than the pseudo-first-order model. Moreover, the study found that the lignin content of the biochar plays a major role in determining the adsorption capacity. The surface characteristics of biochar, influenced by the types of agricultural residues and preparation temperature, directly impact its adsorption mechanism and capacity. While biochar produced at 300 °C showed optimal Cd(II) adsorption, those processed at 600 °C were less effective, likely due to the loss of functional groups at higher temperatures. [ABSTRACT FROM AUTHOR]

A mussel-inspired multiwalled carbon nanotube (MWCNT) nanocomposite (MWCNTs@CCh-PEI) was prepared by the co-deposition of catechol (CCh)/polyethyleneimine (PEI) and modification of MWCNTs for the efficient removal of methyl orange (MO). The effects of MO solution pH, contact time, initial MO concentration, and temperature on the adsorption capacity of MWCNTs@CCh-PEI were investigated. The results indicate that the adsorption capacity of MWCNTs@CCh-PEI was two times higher than that of pristine MWCNTs under the same conditions. The adsorption kinetics followed the pseudo-second-order model, suggesting that the adsorption process was chemisorption. The adsorption isotherm shows that the experimental data were fitted well with the Langmuir isotherm model, with a correlation coefficient of 0.9873, indicating that the adsorption process was monolayer adsorption. The theoretical maximum adsorption capacity was determined to be 400.00 mg·g−1. The adsorption thermodynamic data show that the adsorption process was exothermic and spontaneous. More importantly, the adsorption capacity of MWCNTs@CCh-PEI showed no significant decrease after eight reuse cycles. These results demonstrate that MWCNTs@CCh-PEI is expected to be an economical and efficient adsorbent for MO removal. [ABSTRACT FROM AUTHOR]

Exploring highly active electrocatalysts as platinum (Pt) substitutes for the oxygen reduction reaction (ORR) remains a significant challenge. In this work, single Mn embedded nitrogen-doped graphene (MnN4) with and without halogen ligands (F, Cl, Br, and I) modifying were systematically investigated by density functional theory (DFT) calculations. The calculated results indicated that these ligands can transform the dyz and dxz orbitals of Mn atom in MnN4 near the Fermi-level into d z 2 orbital, and shift the d-band center away from the Fermi-level to reduce the adsorption capacity for reaction intermediates, thus enhancing the ORR catalytic activity of MnN4. Notably, Br and I modified MnN4 respectively with the lowest overpotentials of 0.41 and 0.39 V, possess superior ORR catalytic activity. This work is helpful for comprehensively understanding the ligand modification mechanism of single-atom catalysts and develops highly active ORR electrocatalysts. [ABSTRACT FROM AUTHOR]

It is important to develop effective strategies for enhancing the removal capacity of aromatic volatile organic compounds (VOCs) by modifying conventional porous adsorbents. In this study, a novel HZSM-5 zeolite-supported sulfonic acid (ZSM−OSO3H) was prepared through ClSO3H modification in dichloromethane and employed for the elimination of gaseous o-xylene. The ClSO3H modification enables the bonding of −OSO3H groups onto the HZSM-5 support, achieving a loading of 8.25 mmol·g−1 and leading to a degradation in both crystallinity and textural structure. Within an active temperature range of 110–145 °C, ZSM−OSO3H can efficiently remove o-xylene through a novel reactive adsorption mechanism, exhibiting a removal rate exceeding 98% and reaching a maximum breakthrough adsorption capacity of 264.7 mg. The adsorbed o-xylene derivative is identified as 3,4-dimethylbenzenesulfonic acid. ZSM−OSO3H demonstrates superior adsorption performance for o-xylene along with excellent recyclability. These findings suggest that ClSO3H sulfonation offers a promising approach for modifying various types of zeolites to enhance both the elimination and resource conversion of aromatic VOCs. [ABSTRACT FROM AUTHOR]

Many wastewater treatment methods have been developed because large amounts of organic pollutants (OPs) entered into the water bodies and adsorption is one of the classic and important technologies. Recently, magnetic adsorbents have garnered extensive attention due to the high efficiency and distinctive recyclability. The control of their structures and surface properties is crucial. Here, the magnetite@carbon (Fe3O4@C) composite was prepared by coupling microreactor and pyrolysis reactor. The structures and surface properties of the Fe3O4@C were effectively adjusted by changing the pyrolysis temperature and Na2CO3 concentration. The Fe3O4@C composite prepared at 800°C of pyrolysis temperature with 1 mol·L−1 of Na2CO3 concentration has lipophilicity and the highest adsorption capacity of 92# gasoline among those adsorbents, which is as high as 7.6 g·g−1. The Fe3O4@C synthesized at 500°C with 1 mol·L−1 of Na2CO3 concentration has hydrophilicity and the highest adsorption capacity of Rhodamine B and Methyl Blue. The saturated adsorption capacities are about 166 and 301 mg·g−1, respectively. Fe3O4@C can be easily separated from wastewater and simply regenerated with less capacity loss after five cycles. The results show that the Fe3O4@C prepared by this method could be suitable for the removal of different OPs by adjusting the preparation conditions. Magnetic adsorbents Fe3O4@C were prepared by coupling microreactor and pyrolysis reactor. Structure and property of Fe3O4@C were effectively controlled by adjusting reaction parameters. Fe3O4@C composite exhibits outstanding adsorption performances for different organic pollutants. Fe3O4@C composite shows excellent recyclability and reusability. The adsorption kinetics fitted the pseudo-second-order model. [ABSTRACT FROM AUTHOR]

In this work, we employ an eco-friendly and highly efficient method for the successful removal of anionic azo dye (CR) using emerging Ni/Co-BTC hollow Metal-Organic Frameworks (MOFs). The MOFs was developed via a solvothermal synthesis method. Various kinetic models, adsorption capacities, isotherms (Langmuir and Freundlich), and thermodynamic stability assessments were used to predict the adsorption mechanism and the types of interactions present between CR dyes and Hollow MOFs. Our findings suggest that the adsorption process follows Freundlich isotherm, with PSO kinetic models indicating chemisorption and a maximum Langmuir adsorption capacity of 168.03 mgg−1. We observed a removal efficiency of 74% in neutral medium and 85% in acidic medium. Thermodynamic studies reveal the spontaneity of the process with endothermic enthalpy, attributed to the hydrogen bonding and electrostatic interactions between the dye molecule and the adsorbent. Furthermore, to investigate practical applicability, we conducted studies in real water and dye mixtures. All studies demonstrated that the prepared Ni/Co-BTC hollow MOFs show promising potential adsorbents for the CR dye removal from the wastewater, owing to their high efficiency and reusability. Adsorption of anionic dyes in hollow MOFs High adsorption capacity obtained from adsorption isotherm studies High efficiency for Congo red and mixture of dyes Adsorption process is highly spontaneous and endothermic [ABSTRACT FROM AUTHOR]

This study aims to establish a method for purifying total flavonoids in roses using macroporous resin columns, intending to leverage and harness their potential. We screened six macroporous resins to evaluate their capacity for their adsorption and desorption, ultimately identifying X5 macroporous resin as the most effective. To comprehensively understand the adsorption behavior, we analyzed it using various models, such as pseudo-first-order and pseudo-second-order kinetic models, particle diffusion models, and Langmuir, Freundlich, and Temkin isotherm models. Employing both single-factor and uniform design, approaches, the focus of this work was on maximizing the total flavonoid recovery rate. A 3-factor and 10-level uniform design table was utilized for optimizing the optimal process parameters and exploring the antioxidant properties of the purified flavonoids. The optimal process conditions for purifying total flavonoids from roses can be summarized as follows: a sample concentration of 2 mg/mL, pH at 2, 55 mL sample volume, eluent ethanol concentration of 75%, eluent volume of 5 BV, and the elution rate set at 1 mL/min. Following purification, the total flavonoid content peaked at 57.82%, achieving an 84.93% recovery rate, signifying substantial antioxidant potential. Consequently, the method established for purifying TFR using X5 macroporous resin in this study proves to be a dependable and reliable method consistent approach. [ABSTRACT FROM AUTHOR]

Electrocatalytic conversion of biomass‐derived 5‐hydroxymethylfurfural (HMF) to value‐added 2,5‐furandicarboxylic acid (FDCA) is of great significance in compensating for the rapid consumption of fossil resources. However, it is a challenge to further improve the performance of HMF electrocatalytic oxidation (HMFOR) by synergistic kinetics (active sites) and thermodynamics (adsorption sites). In this work, Al(OH)3/Co(OH)2 is successfully fabricated as an efficient catalyst, and its catalytic mechanism for HMF oxidation is clarified. Extended X‐ray absorption fine structure (EXAFS) analysis demonstrate that electrochemically generated Co3+ is the main catalytic site for HMF oxidation. The HMF equilibrium adsorption capacity of Al(OH)3 reach 57.0 mg g−1, which effectively increase the initial concentration of substrate and promoted the reaction rate. The combined results, based on 24 stable cycles and an FDCA yield retention rate of 98.6% after 180 days, are the highest ever achieved. Additionally, it is shown that this system can oxidize four other biomass‐derived substrates. Therefore, this work provides insight into a hydroxide catalyst that owes its efficiency to synergy between active and adsorption sites. [ABSTRACT FROM AUTHOR]