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The ionic liquid-integrated aqueous electrolyte was designed to remodel the interfacial electrical double layer with simultaneously manipulating solvation chemistry and adsorption situation on the Zn anode, which facilitates the Zn(H 2 O) 6 2+ desolvation process and Zn ion flux, thus enabling an excellent Zn plating/stripping cycling stability with negligible by-products and Zn-dendrites. [Display omitted] Zn anodes suffer from poor reversibility and stability owing to nonuniform dendrite growth and self-corrosion. Here, 1-ethyl-3-methylimidazolium acetate (EMImAc) is introduced to reconstruct interfacial electrical double layer with simultaneously manipulating the solvation environment and the adsorption situation on Zn anode. The acetate anions with high nucleophilicity can effectively alter the solvation shell around Zn2+ ions and immobilize the H 2 O molecules, thus weakening water activity and alleviating water-related parasitic reactions. Concomitantly, both the imidazolium cation and acetate anion are inclined to gather on Zn anode surface for constructing an electrostatic shielding layer, and meanwhile the chemisorbed acetate anions also contribute to accelerate the Zn(H 2 O) 6 2+ desolvation process. Such a synergistic effect enables uniform electric field distribution and facilitates Zn ion flux, which mitigates the random diffusion of Zn2+ and finally promotes the dendrite-free deposition. As a result, the Zn/Zn symmetric cells with EMImAc-integrated aqueous electrolyte realize an excellent cycling lifespan of 7000 h (0.5 mA cm−2/0.25 mAh cm−2) and high Zn utilization of 61.3 % (15 mA cm−2/20 mAh cm−2). Furthermore, the effective of EMImAc additive is demonstrated in Zn/V 2 O 5 cells. This work offers insights into the ionic liquid-integrated aqueous electrolytes to enhance the interface stability of Zn anode for rechargeable zinc batteries. [ABSTRACT FROM AUTHOR]

Magnetic activated carbon has been proved its separation ability to overcome a main drawback of activated carbon powder. However, effect of magnetization method on characterizations and Chromium (VI) adsorption of this adsorbent from Artocarpus Heterophyllus Peel (jackfruit peel) has not been investigated yet. This study magnetized jackfruit peel activated carbon using thermochemical and co-precipitation methods. Magnetic jackfruit activated carbon (MJAC) were examined and compared to jackfruit activated carbon (JAC) for surface chemistry, texture, morphology and crystalline properties. The isotherm/kinetics of Cr(VI) adsorption on these adsorbents were also analyzed. The results showed that all the adsorbents showed a typical peak of –(COO)n–Fe of iron oxide particles and functional groups but the adsorbent prepared with thermochemical method had the greatest Fe–O–C bond signal. The thermochemical adsorbent also had various particles of Fe3O4, Zero Valent Iron, and α-Fe2O3 while the co-precipitation absorbents gave a greater mesoporous structure and specific surface area than their JAC precursor; especially the adsorbent produced at mild temperature was covered by the highest iron oxide distribution on the surface and better magnetite property. As a result of the high specific surface area, these co-precipitation adsorbents were more effective for Cr(VI) adsorption than others. The PSO model best describes Cr(VI) adsorption on all absorbents with and without magnetite. Cr(VI) adsorption on JAC was dominated by intra-particle diffusion while multistep processes, including external mass transfer, governed the overall MJAC adsorption process. This work has created jackfruit peel-based magnetic activated carbon for wastewater treatment to remove toxic heavy metals and promote the circular economy that uses solid wastes as raw materials. Highlights: The first investigation of magnetic jackfruit peel-based activated carbon for Cr(VI) removal application. Physico-chemical properties and Cr(VI) adsorption of magnetite absorbents affected by magnetization methods of thermochemical and co-precipitation A strong attraction of iron oxide particles with carbon and various types of iron particles were observed in thermochemical adsorbent whereas the development of mesoporous structure and specific surface area were found in co-precipitation adsorbent [ABSTRACT FROM AUTHOR]

In exploring the potential of agricultural waste as an efficient adsorbent, acid‐activated coconut husk biochar was prepared, characterized and applied to remove amoxicillin from wastewater. The mechanism of adsorption was also investigated through isotherm and kinetic studies. The biochar was activated with HNO3 for 2 h at 25°C and investigated under varying experimental conditions of pH (1–11), initial amoxicillin concentration (0.5–2.5 mg/L), adsorbent dosage (2–20 mg) and contact time (0–24 h). The adsorption process was characterized by rapid attainment of adsorption equilibrium and high values of adsorption capacity. Acid activation had a significant impact on the adsorptive capacity of biochar as removal efficiency improved from 90% (over an hour) to 98.9% (within 40 min). The FTIR results confirmed the characteristic adsorption peaks of C‐H, =C‐H, C=C, C‐O, C=O and O‐H, suggesting the dominant presence of aromatic and carbonyl functional groups on the surface of the biochar. Adjustments in peak shapes and transmittance were observed for these functional groups after the adsorption; highlighting the likely interaction between the biochar and the amoxicillin during the adsorption which has been succinctly proposed. The SEM micrographs showed the growth of leaf‐like flakes of irregular shapes and pores essential for the adsorption. The rate and mechanism of adsorption were driven by the variable surface charge of the adsorbent and the degree of ionization of the adsorbates, which were largely controlled by the solution pH. Adsorption rates were highest in the acidic medium, peaking around a pH of 3, then remained relatively stable between pHs of 5 and 7 before reducing dramatically with increasing pH in the alkaline region. The adsorption best followed the Langmuir model of isotherm while the kinetics mimicked the pseudo–second order (PSO). The findings suggest that HNO3‐activated coconut biochar is a promising, low‐cost and porous adsorbent effective for amoxicillin removal. [ABSTRACT FROM AUTHOR]

Cyclohexane is a high-valued chemical rece1vmg significant interest in liquid hydrogen storage technology. TiO2-based catalysts show high performance in the photocatalytic dehydrogenation of cyclohexane under mild conditions, but the detailed reaction mechanism is not well understood. With the surface science approaches, we have studied the adsorption and surface chemistry of cyclohexane on rutile TiO2(110). The thermal desorption spectroscopy and X-ray photoelectron spectroscopy results both demonstrate the molecular adsorption of cyclohexane on rutile TiO2(110). Upon the UV Hg light irradiation, photodesorption of cyclohexane occurs from both the chemisorbed monolayer and the multilayer. No decomposition nor dehydrogenation of cyclohexane occurs on rutile TiO2(110). These results deepen the fundamental understanding of the surface chemistry of cyclohexane on the TiO2 surface. [ABSTRACT FROM AUTHOR]

In this perspective we discuss the progress made in the mechanistic studies of the surface chemistry associated with the atomic layer deposition (ALD) of metal films and the usefulness of that knowledge for the optimization of existing film growth processes and for the design of new ones. Our focus is on the deposition of late transition metals. We start by introducing some of the main surface-sensitive techniques and approaches used in this research. We comment on the general nature of the metallorganic complexes used as precursors for these depositions, and the uniqueness that solid surfaces and the absence of liquid solvents bring to the ALD chemistry and differentiate it from what is known from metalorganic chemistry in solution. We then delve into the adsorption and thermal chemistry of those precursors, highlighting the complex and stepwise nature of the decomposition of the organic ligands that usually ensued upon their thermal activation. We discuss the criteria relevant for the selection of co-reactants to be used on the second half of the ALD cycle, with emphasis on the redox chemistry often associated with the growth of metallic films starting from complexes with metal cations. Additional considerations include the nature of the substrate and the final structural and chemical properties of the growing films, which we indicate rarely retain the homogeneous 2D structure often aimed for. We end with some general conclusions and personal thoughts about the future of this field. [ABSTRACT FROM AUTHOR]

This study investigates the production of biochar from fresh wood shavings (B-WSF) and used wood shavings (B-WSU–animal litter) biomass through pyrolysis at 450 °C and explores its potential for NO2 adsorption at different temperatures from 22 °C to 250 °C. The biochars' thermal stability, elemental composition, mineral content, textural properties, and surface chemistry were comprehensively analyzed using various techniques, including thermogravimetric analysis (TGA), ultimate analysis, proximate analysis, mineral composition analysis, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and NO2 adsorption experiments. The results indicate that biochars derived from WSF and WSU biomass possess high stability and exhibit significant changes in their elemental composition, surface functional groups, and textural properties compared to the raw biomass. The biochars demonstrated substantial NO2 adsorption capacities and reduction, with B-WSU biochar exhibiting higher adsorption capacity attributed to its higher specific surface area, mineral content, and functional groups. In addition, the results reveal distinct patterns in NO2 adsorption and NO release, with temperature playing a pivotal role in the process. At lower temperatures, NO2 adsorption on both biochars exhibits gradual increases, while higher temperatures facilitate immediate adsorption and subsequent reduction to NO. The adsorption of NO2 increased with increasing adsorption temperature, with B-WSU biochar achieving a maximum adsorption capacity of 43.54 mg/g at 250 °C, compared to 9.62 mg/g for B-WSF biochar. Moreover, XPS analysis revealed alterations in surface functional groups upon NO2 exposure, indicating enhanced surface oxidation and formation of nitrogen-containing species. In addition, differences in surface heterogeneity and mineral content influence NO2 adsorption behavior between the biochar samples. These findings highlight the potential of WSF biomass-derived biochar as an effective adsorbent for NO2 removal, offering insights into its application in air pollution mitigation strategies. The mechanism of NO2 adsorption involves chemisorption on oxygen-containing functional groups and physical adsorption, facilitated by the high specific surface area and pore volume of the biochar. Furthermore, the rich mineral content in B-WSU biochar explains its high adsorption capacity, demonstrating the potential for valorization of waste materials in the circular economy. [ABSTRACT FROM AUTHOR]

Gas adsorption on solid surfaces can be categorized into two types: physical adsorption and chemical adsorption. By applying knowledge of surface chemistry, this study aims to simulate and analyze experimental results in the resistive gas sensing process. The objective is to investigate the adsorption behavior and utilize it as research material for undergraduate innovation and entrepreneurship projects and undergraduate thesis designs. This research will enhance students’ understanding of gas-solid adsorption principles, improve their ability to apply theory to practice, and cultivate their scientific research skills. [ABSTRACT FROM AUTHOR]

Biochar has proven effective in the remediation of excess nitrogen from soil and water. Excess nitrogen from agricultural fields ends up in aquatic systems and leads to reduced water quality and the proliferation of invasive species. This study aimed to assess the efficiency of chemically surface-modified biochar produced from invasive Pistia stratiotes L. for the adsorption of inorganic nitrogen (NH4+ and NO3−). Biochar structure was investigated using scanning electron microscopy, energy-dispersive X-ray analysis, X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, and inductively coupled plasma mass spectrometry. The results from adsorption experiments indicate that NH4+ removal was optimal (0.8–1.3 mg N g−1) at near-neutral pH levels (6.0–7.5), while NO3− removal was optimal (0.4–0.8 mg N g−1) under acidic pH conditions (4.8–6.5) using the modified biochar. These findings highlight the significance of solution pH, biochar morphology, and surface chemistry in influencing the adsorption of NH4+ and NO3−. However, further studies are necessary to assess the potential oxidative transformation of NH4+ to NO3− by biochar, which might have contributed to the reduction in NH4+ in the aqueous phase. [ABSTRACT FROM AUTHOR]

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This study investigates polyethylene glycol (PEG) homopolymer thin film adsorption on gold surfaces of controlled surface chemistry. The conformational states of physisorbed PEG are analyzed through polarization modulation infrared reflection–absorption spectrometry (PM-IRRAS). The PM-IRRAS principle is based on specific optical selection rules allowing the detection of surface-specific FTIR response of thin polymer films on the basis of differential reflectivity at the polymer/substrate interface for p- and s-polarized light. The intensification of the electric field generated at the PEG/substrate interface for p-polarized IR light in comparison with s-polarized light permits the analysis of PEG chain anisotropy and conformational changes induced by the adsorption. Results showed that PEG adsorbs on model substrates having a rather hydrophilic character in a way that the PEG chains spread parallel to the surface. In the case of a very hydrophilic substrate, the adsorbed PEG chains are in a stable thermodynamic state which allows them to arrange and crystallize as stacked crystalline lamellae after adsorption. The surface topography and morphology of the PEG thin films were also investigated by atomic force microscopy (AFM). While in the bulk state, PEG crystallizes in the form of large spherulites; on substrates whose adsorption is favored by surface chemistry, PEG crystallizes in the form of stacked lamellae with a thickness equal to 20 nm. Conversely, on a hydrophobic substrate, the PEG chains do not crystallize and adsorption occurs in the statistical coil state. [ABSTRACT FROM AUTHOR]

Blood-contacting medical devices often succumb to thrombosis, limiting their durability and safety in clinical applications. Thrombosis is fundamentally initiated by the nonspecific adsorption of proteins to the material surface, which is strongly governed by thermodynamic factors established by the nature of the interaction between the material surface, surrounding water molecules, and the protein itself. Along these lines, different surface materials (such as polymeric, metallic, ceramic, or composite) induce different entropic and enthalpic changes at the surface–protein interface, with material wettability significantly impacting this behavior. Consequently, protein adsorption on medical devices can be modulated by altering their wettability and surface energy. A plethora of polymeric coating modifications have been utilized for this purpose; hydrophobic modifications may promote or inhibit protein adsorption determined by van der Waals forces, while hydrophilic materials achieve this by mainly relying on hydrogen bonding, or unbalanced/balanced electrostatic interactions. This review offers a cohesive understanding of the thermodynamics governing these phenomena, to specifically aid in the design and selection of hemocompatible polymeric coatings for biomedical applications. Blood-contacting medical devices often succumb to thrombosis, limiting their durability and safety in clinical applications. A plethora of polymeric coating modifications have been utilized for addressing this issue. This review offers a cohesive understanding of the thermodynamics governing these phenomena, to specifically aid in the design and selection of hemocompatible polymeric coatings for biomedical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Homogenous enantioselective catalysis is nowadays the cornerstone in the manufacturing of enantiopure substances, but its technological implementation suffers from well‐known impediments like the lack of endurable catalysts exhibiting long‐term stability. The catalytically active intermetallic compound Palladium‐Gallium (PdGa), conserving innate bulk chirality on its surfaces, represent a promising system to study asymmetric chemical reactions by heterogeneous catalysis, with prospective relevance for industrial processes. Here, this work investigates the adsorption of 10,10′‐dibromo‐9,9′‐bianthracene (DBBA) on the PdGa:A(1¯1¯1¯$\bar{1}\bar{1}\bar{1}$) Pd3‐terminated surface by means of scanning tunneling microscopy (STM) and spectroscopy (STS). A highly enantioselective adsorption of the molecule evolving into a near 100% enantiomeric excess below room temperature is observed. This exceptionally high enantiomeric excess is attributed to temperature activated conversion of the S to the R chiral conformer. Tip‐induced bond cleavage of the R conformer shows a very high regioselectivity of the DBBA debromination. The experimental results are interpreted by density functional theory atomistic simulations. This work extends the knowledge of chirality transfer onto the enantioselective adsorption of non‐planar molecules and manifests the ensemble effect of PdGa surfaces resulting in robust regioselective debromination. [ABSTRACT FROM AUTHOR]

The growing need to examine the adsorption capabilities of innovative materials in real-world water samples has encouraged a shift from single to multicomponent adsorption systems. In this study, a novel composite, PANI-g-SM was synthesized by covalently grafting a lignocellulosic biomass, Saccharum munja (SM) with polyaniline (PANI). The as-synthesized composite was investigated for the simultaneous adsorption of cationic (Methylene Blue (MB); Crystal Violet (CV)) and anionic dyes (Reactive Red 35 (RR); Fast Green FCF (FG)) from four single components and two binary systems, MB + RR and CV + FG. Further, the effect and interaction of pH (2–11), dosage (0.01–0.04 g/10 mL), and initial concentration (0.0313 to 0.1563 mmol/L) on the elimination of dyes by PANI-g-SM were studied through a novel design of Box-Behnken of Response Surface Methodology (RSM) technique which was found to be highly useful for revealing the chemistry of interfaces in multi-component systems. The extended Langmuir model for the binary system indicated the presence of synergism, as result the maximum monolayer adsorption capacity increased by 44.44%, 645.83%, 67.88%, and 441.07% for MB, RR, CV, and FG dye, respectively. Further, the adsorption process mainly followed a pseudo-second-order kinetic model, and the thermodynamic studies revealed the exothermic nature of adsorption for RR and FG dye while endothermic for MB and CV dye, respectively with Δ G varying from − 1.68 to − 6.12 kJ/mol indicating the spontaneity of the process. Importantly, the efficacy of the composite was evaluated for the treatment of textile industry effluent highlighting its potential as an adsorbent for wastewater treatment. [ABSTRACT FROM AUTHOR]

The issue of cigarette butts is an environmental crisis that has affected the world. Despite their small size, CBs are one of the most common types of solid waste found in public places, particularly in coastal areas. The aim of this study was to investigate the adsorption behavior of microfibers obtained from cigarette butts on tetracycline before and after aging. 1 g of CBs was added to 50 mL of distilled water and stirred at 220 rpm for 2 h, then filtered through Whatman 0.45 µm filter paper, and the resulting MFs were dried at 60 °C for 24 h. To simulate aging, the MFs were subjected to an ultrasonic treatment at a frequency of 80 Hz and a power of 70 W for 4 h. The adsorption behavior of aged and fresh MFs was investigated using solutions containing TTC in the range of 5–20 mg/L. This study showed that ultrasonically aged MFs had a greater tendency to adsorb TTC than fresh MFs due to an increased surface area and changes in surface chemistry. It can be concluded that as the age of MFs increases, they adsorb more concentration of pollutants. This can lead to increased contamination of MFs in the presence of contaminants. [ABSTRACT FROM AUTHOR]

Adsorption isotherms of pure vapors and vapor mixtures of water, methanol, and cyclohexane were studied using a synthesized 13X zeolite (FAU topology), by means of a DVS gravimetric vapor analyzer. These results were validated by GCMC calculations. The surface chemistry of the adsorbent was characterized by the thermodesorption of ammonia, and its textural properties were studied using nitrogen physisorption. The 13X zeolite was found to be strongly acidic (BrØnsted acid sites, Si/Al = 1.3) and its specific surface area around 1100 m2·g−1. Water was found to be able to diffuse within both the supercages and the sodalite cavities of the FAU structure, whereas methanol and cyclohexane were confined in the supercages only. The water/methanol sorption selectivity of the 13X zeolite was demonstrated by co-adsorption measurements. The composition of the water/methanol adsorbed phase could be calculated by assuming IAST hypotheses. This model failed in the case of the water/cyclohexane co-adsorption system, which is in line with the non-miscibility of the components in the adsorbed state. The sorption isotherms could be successfully simulated, confirming the robustness of the forcefields used. The 13X zeolite confirmed its a priori expected hydrophilic nature, which is useful for the selective adsorption of water in a methanol–water vapor mixture. [ABSTRACT FROM AUTHOR]

The production of affordable advanced porous materials is necessary for applications involving the capture of CO2. This study aimed to investigate the use of inexpensive liquid precursors in the production of CO2 sorbents. Porous precursors were produced through solvothermal processing of ethylene glycol via dehydration using sulfuric acid. Various pyrolysis and activation techniques were utilized on a carbon precursor to examine how different heat treatment methods affect surface chemical properties and the behavior of static CO2 adsorption at temperatures of 273 K, 298 K, and 313 K. Out of the studied carbons, the urea‐treated pyrolyzed sample exhibited a CO2 uptake capacity of 0.93 mmol g−1 at a pressure of 0.15 bar and a temperature of 298 K. This carbon exhibited a remarkable CO2/N2 selectivity of 46, mainly due to its microporosity and a nitrogen content of 8.3 atomic percent. Moreover, the investigation of adsorption and chemical properties unveiled that nonoxidized sulfur exhibits favorable effects on CO2 adsorption, particularly at the temperature of 298 K. This study provides evidence that liquid precursors can be effectively employed to generate porous doped functional carbons or precursors using solvothermal conditions. [ABSTRACT FROM AUTHOR]

MXene, a two-dimensional (2D) nanomaterial with diverse applications, has gained significant attention due to its 2D lamellar structure, abundance of surface groups, and conductivity. Despite various established synthesis methods since its discovery in 2011, MXenes produced through different approaches exhibit variations in structural and physicochemical characteristics, impacting their suitability for environmental application. This study delves into the effect of synthesis conditions on MXene properties and its adsorption capabilities for four commonly prescribed antibiotics. We utilized material characterization techniques to differentiate MXenes synthesized using three prevalent etchants: hydrofluoric acid (HF), mixed acids (HCl/HF), and fluoride salts (LiF/HCl). Our investigation of adsorption performance included isotherm and kinetic analysis, complemented by density functional theory calculations. The results of this research pinpointed LiF/HCl as an efficient etchant, yielding MXene with favorable morphology and surface chemistry. Electrostatic interactions and hydrogen bonding between MXene surface terminations and ionizable moieties of the antibiotic molecules emerge as pivotal factors in adsorption. Specifically, a higher presence of oxygen terminations increases the binding affinities. These findings provide valuable guidance for etchant selection in environmental applications and underscore the potential to tailor MXenes through synthesis conditions to design membranes capable of selectively removing antibiotics and other targeted substances. [ABSTRACT FROM AUTHOR]

Contamination of the aqueous environment caused by the presence of heavy metal ions and oils is a growing concern that must be addressed to reduce their detrimental impact on living organisms and safeguard the environment. Recent efficient and environmentally friendly remediation methods for the treatment of water are based on third-generation bioaerogels as emerging applications for the removal of heavy metal ions and oils from aqueous systems. The peculiarities of these materials are various, considering their high specific surface area and low density, together with a highly porous three-dimensional structure and tunable surface chemistry. This review illustrates the recent progress in aerogels developed from cellulose and chitosan as emerging materials in water treatment. The potential of aerogel-based adsorbents for wastewater treatment is reported in terms of adsorption efficacy and reusability. Despite various gaps affecting the manufacturing and production costs of aerogels that actually limit their successful implementation in the market, the research progress suggests that bio-based aerogels are ready to be used in water-treatment applications in the near future. [ABSTRACT FROM AUTHOR]

This study analyzes the adsorption of two model pesticides, namely, 2,4-dichlorophenoxyacetic acid (2,4-D) and carbofuran on activated carbons obtained by chemical activation with phosphoric acid of peach stones. The effect of the synthesis conditions on the surface area development was analyzed. The highest surface area was obtained with an impregnation time of 5 h, an impregnation ratio equal to 3.5, an activation temperature of 400 °C, and 4.5 h of activation time. Under these conditions, the maximum specific surface area was equal to 1182 m2·g−1 which confirms the high porosity of the activated carbon, predominantly in the form of micropores. The surface chemistry of this activated carbon was also characterized using pH at point of zero charge, scanning electron microscopy, and Fourier transform infrared spectroscopy. Both kinetics and equilibrium adsorption tests were performed. Adsorption kinetics confirmed that 2,4-D adsorption follows a pseudo first-order adsorption kinetic model, while carbofuran adsorption is better described by a pseudo second-order one. Regarding the equilibrium adsorption, a higher adsorption capacity is obtained for 2,4-D than carbofuran (c.a. 500 and 250 mg·g−1, respectively). The analysis of the thermodynamics and characterization after use suggest a predominantly physisorption nature of the process. [ABSTRACT FROM AUTHOR]

The purpose of this research was to synthesise the chitosan-polyacrylamide composite (CH-PAA) and follow up with an investigation of its capacity to adsorb anionic Sirius yellow K-CF dye, under different environmental conditions. In order to increase the uptake value of the synthesised CH-PAA, the surface chemistry of this adsorbent was modified by bringing it into contact with ZnO nanoparticles (CH-PAA-ZnO). The characterisation tests using XRD, FT-IR, TEM, and FE-SEM analyses demonstrated the successful loading of ZnO onto the CH-PAA surface without causing damage to the chemical composition of the original materials. Excellent removal efficiency of the Sirius yellow K-CF dye (≈ 100%) by CH-PAA-ZnO was performed under the conditions cited namely, pH of 2, dye concentration of20 mg/L, adsorbent dosage of 0.05 g/L, temperature of 40°C, and contact time of 90 minutes. It was evident that the ZnO nanoparticles strongly facilitate the removal process, in which 42% enhancement of dye removal efficiency was recorded, after the CH-PAA was modified with these nanoparticles. The values of the thermodynamic parameters determined at different concentrations of Sirius yellow K-CF dye (negative $$\Delta {{\rm{G}}^{\rm{o}}}$$ Δ G o values; and positive $$\Delta {{\rm{H}}^{\rm{o}}}$$ Δ H o and $$\Delta {{\rm{S}}^{\rm{o}}}$$ Δ S o values) indicated that the dye adsorption process onto the CH-PAA-ZnO was favourable, spontaneous, and endothermic. Based on the R2 values (> 0.99) of the linear fitting determined, the experimental data pertinent to the isotherm and kinetic studies are represented by the Langmuir isotherm and pseudo-second-order kinetic formulas, respectively. Also, the isotherm study revealed that 1 g of CH-PAA-ZnO was capable of capturing 149.79 mg of the dye molecules in 1 L aqueous solution. On comparison with the other adsorbent used for the same purpose, the CH-PAA-ZnO can be an efficacious adsorbent and a good alternative to treat wastewater containing Sirius yellow K-CF dye, in an acidic medium. [ABSTRACT FROM AUTHOR]

Recently, considerable attention has been given to using magnetic nanoparticles (MNPs) for capturing oil from oil-in-water (O/W) emulsions, despite MNPs' inherent instability and agglomeration. Their stabilization through changing surface chemistry is required to increase dispersivity. In this research, we use cetyltrimethylammonium bromide (CTAB) as a cationic surfactant to increase the positive surface charge of the particles, resulting in a better stability in the aqueous solution because of increased repulsive forces. The functionalized MNPs are characterized using transmission electron microscopy (TEM), zeta potential, and contact angle (CA) measurements. The aim of this study is to investigate the oil separation efficiency (SE) and equilibrium oil adsorption capacity of the synthesized particles, which are determined using gas chromatography analysis. We also study the adsorption behavior using isotherm and kinetic models. The SE values indicate the superior performance of MNP@CTAB for oil adsorption from dodecane-in-water nanoemulsion (SE = 99.80%) compared to the bare MNPs with SE of approximately 57.46%. These findings are attributed to the stronger electrostatic attraction between the MNP@CTAB having high positive charge and negatively charged oil droplets. The adsorption isotherm results using both linear and non-linear regression methods show that the Freundlich isotherm is the best fit to the experimental equilibrium data (with calculated R2 > 0.97), verifying a multilayer heterogeneous adsorption. Moreover, the pseudo-first-order kinetic model describes the experimental equilibrium data in a greater congruence (R2 = 0.99), suggesting physical adsorption of oil onto MNPs through van der Waals and physical bonding, which is also confirmed through zeta potential measurements. [ABSTRACT FROM AUTHOR]

Chlorphenamine (CPA) adsorption onto three activated carbons (ACs), namely, Megapol M (MM), Micro 10 (M10), and GAMA B (GB), was studied in this work. The textural properties, concentrations of active sites, surface charge and point of zero charge of the ACs were assessed. The surface areas (SBET) of MM, GB and M10 were 1107, 812 and 766 m2/g, respectively. The MM surface had an acidic character, while the surfaces of M10 and GB were basic. The adsorption capacity of MM, M10, and GB towards CPA was studied at pH 7 and 11, and the adsorption capacity decreased in the order MM > M10 ≈ GB, which was ascribed to the magnitude of SBET and the concentration of acidic sites. The solution pH significantly increased the adsorption capacity of MM towards CPA by raising the solution pH from 5 to 9, and this behavior was attributed to the electrostatic attraction between the negatively charged surface of MM and the cationic species of CPA. The maximum uptake of CPA adsorbed on MM was 574.6 mg/g at pH = 11 and T = 25 °C. The adsorption capacity of MM was slightly raised by incrementing the temperature. Lastly, the zeta potential measurements of pristine MM and MM saturated with CPA confirmed that the electrostatic attraction predominated in the pH range of 5–9, and the π-π stacking interactions were the principal mechanism of CPA adsorption on MM at pH 11. [ABSTRACT FROM AUTHOR]

Protein adsorption behavior can play a critical role in defining the outcome of a material by affecting the subsequent in vivo response to it. To date, the effect of surface properties on protein adsorption behavior has been mainly focused on surface chemistry, but research on the effect of nanoscale surface topography remains limited. In this study, the adsorption behavior of human serum albumin, immunoglobulin G, and fibrinogen in terms of the adsorbed amount and conformational changes were investigated on bare and anodized titanium (Ti) samples (40 and 60 V applied voltages). While the surface chemistry, RMS surface roughness, and arithmetic surface roughness of the anodized samples were similar, they had distinctly different nanomorphologies identified by atomic force microscopy and scanning electron microscopy, and the surface statistical parameters, surface skewness Ssk and kurtosis Sku. The Feret pore size distribution was more uniform on the 60 V sample, and surface nanostructures were more symmetrical with higher peaks and deeper pores. On the other hand, the 40 V sample surface presented a nonuniform pore size distribution and asymmetrical surface nanostructures with lower peaks and shallower pores. The amount of surface-adsorbed protein increased on the sample surfaces in the order of Ti < 40 V < 60 V with the predominant factor affecting the amount of surface-adsorbed protein being the increased surface area attained by pore formation. The secondary structure of all adsorbed proteins deviated from that of their native counterparts. While comparing the secondary structure components of proteins on anodized surfaces, it was observed that all three proteins retained more of their secondary structure composition on the surface with more uniform and symmetrical nanofeatures than the surface having asymmetrical nanostructures. Our results suggest that the nanomorphology of the peaks and outer walls of the nanotubes can significantly influence the conformation of adsorbed serum proteins, even for surfaces having similar roughness values. [ABSTRACT FROM AUTHOR]

The thermal chemistry of crotonaldehyde on the surface of a polished polycrystalline copper disk was characterized by temperature-programmed desorption (TPD) and reflection–absorption infrared spectroscopy (RAIRS) and contrasted with previous data obtained on a Pt(111) single crystal substrate. A clear difference in the adsorption mode was identified between the two surfaces, highlighted by the prevalence of RAIRS peaks for the C=C bond on Cu vs for C=O on Pt. Adsorption was also determined to be much weaker on Cu vs Pt, with an adsorption energy on the former ranging from −50 kJ/mol to −65 kJ/mol depending on the surface coverage. The experimental data were complemented by extensive quantum mechanics calculations using density functional theory (DFT) to determine the most stable adsorption configurations on both metals. It was established that crotonaldehyde adsorption on Cu occurs via the oxygen atom in the carbonyl group, in a mono-coordinated fashion, whereas on Pt multi-coordination is preferred, centered around the C=C bond. The contrasting surface adsorption modes seen on these two metals are discussed in terms of the possible relevance to selectivity in single-atom alloy hydrogenation catalysis. [ABSTRACT FROM AUTHOR]

Reduction in the utilization of carbon-based fossil energy is the inevitable pathway to fulfill the net-zero CO2 emission target. Hydrogen, one of favorable clean energy sources, becomes a heat topic at present while its safe and efficient storage remains a challenging issue. The majority of related research focus on the hydrogen injection into salt cavern as well as depleted oil/gas reservoirs, where hydrogen is highly compressed under high pressure. In this research, an alternative approach that stores hydrogen into nanopores using the essential adsorption property is investigated, and so does its advantage over traditional high-pressure injection method. First of all, a mechanical model for density distribution of nanoconfined hydrogen is established by the chemical potential equilibrium principle, in which both intermolecular interactions and molecule-wall interactions are taken into account. Additionally, shift of critical properties taking place in nanopores is coupled as well. Then, the nanoconfined hydrogen adsorption behavior is presented, influence of atmosphere parameters, like pressure and temperature, as well as nanopore physical properties, like pore size and strength the pore wall imposes on hydrogen molecules, are identified. The proposed model can reach excellent agreements with hydrogen adsorption data collected from the existed experiments and molecular simulation, clarifying its reliability. Results show that (a) Adsorption phase thickness approaches 0.5 nm, indicating 1–2 adsorption layers are formed, which is insensitive to pressure or temperature variation; (b) Nanoconfined hydrogen density is able to achieve as great as 7 times bulk-hydrogen density at relatively low pressure, suggesting nanopores could store more hydrogen molecules than the traditional high-pressure injection method; (c) Modifying nanopore surface chemistry to intensify molecule-wall interaction strength is a desirable method to dramatically improve nanoconfined hydrogen adsorption capacity. The research lays a fundamental framework to shed light on hydrogen adsorption from a microscopic viewpoint. [Display omitted] • A theoretical framework for nanoconfined hydrogen storage behavior is established. • Hydrogen amount that stores in nanopores could be over 7 times that regular method. • Thickness of adsorption hydrogen area ranges from 0.3–0.5 nm, 1 ∼ 2-layer molecule. • Intensifying molecule-wall interaction strength contributes to hydrogen storage capacity. • Hydrogen behavior in nanopores is governed by adsorption mechanism at low pressure. [ABSTRACT FROM AUTHOR]

In this study, biocarbon was obtained from the waste material corn digest. Carbon adsorbents were obtained by physical activation of the precursor with CO2. Detailed physicochemical characterization of the biocarbon was carried out using low-temperature nitrogen adsorption/desorption, Boehm titration, zero-charge point (pHpzc) and iodine number. In addition, the sorption capacity of the biocarbon agents towards an aqueous solution of methylene blue and methyl red was determined, and the kinetics of the adsorption process were determined. The biocarbon adsorbents were characterized by an average developed specific surface area covering the range from 320 to 616 m2/g. The sorption capacity of the biocarbon adsorbents against methylene blue ranged from 40 mg/g to 146 mg/g, and for methyl red it covered the range from 31 mg/g to 113 mg/g. It was shown that the efficiency of organic dye removal by the obtained biocarbons depends on the initial concentration of the adsorbate solution, its mass, shaking rate, adsorbent–adsorbate contact time and temperature. The results obtained from the Langmuir and Freundlich kinetic models showed that the Langmuir model is the most suitable model for describing the adsorption of the studied pollutants on biocarbon. In turn, the adsorption kinetics of dyes is described according to the pseudo-second-order model. Adsorption studies also showed that as the process temperature increases, the removal efficiency of methylene blue and methyl red increases. [ABSTRACT FROM AUTHOR]

Adsorption reactions at solid-water interfaces define elemental fate and transport and enable contaminant clean-up, water purification, and chemical separations. For nanoparticles and nanopores, nanoconfinement may lead to unexpected and hard-to-predict products and energetics of adsorption, compared to analogous unconfined surfaces. Here we use X-ray absorption fine structure spectroscopy and operando flow microcalorimetry to determine nanoconfinement effects on the energetics and local coordination environment of trivalent lanthanides adsorbed on Al2O3 surfaces. We show that the nanoconfinement effects on adsorption become more pronounced as the hydration free energy, ΔGhydr, of a lanthanide decreases. Neodymium (Nd3+) has the least exothermic ΔGhydr (−3336 kJ·mol−1) and forms mostly outer-sphere complexes on unconfined Al2O3 surfaces but shifts to inner-sphere complexes within the 4 nm Al2O3 pores. Lutetium (Lu3+) has the most exothermic ΔGhydr (−3589 kJ·mol−1) and forms inner-sphere adsorption complexes regardless of whether Al2O3 surfaces are nanoconfined. Importantly, the energetics of adsorption is exothermic in nanopores only, and becomes endothermic with increasing surface coverage. Changes to the energetics and products of adsorption in nanopores are ion-specific, even within chemically similar trivalent lanthanide series, and can be predicted by considering the hydration energies of adsorbing ions. Understanding adsorption reactions at solid–water interfaces is key to enabling important chemical separations; however, when such surfaces are confined in nanopores, nanoconfinement effects on surface chemistry are difficult to predict. Here, X-ray absorption fine structure spectroscopy and operando flow microcalorimetry are used to determine the effects of nanoconfinement on the energetics and coordination environments of trivalent lanthanides adsorbed on alumina surfaces within nanopores. [ABSTRACT FROM AUTHOR]

Solid adsorbents are considered very attractive for selective CO2 removal from main emission sites, and this method was found suitable for post-combustion carbon capture owing to its cost-effective and retrofit nature. Among various solid adsorbents contested for CO2 adsorption, biomass-derived porous carbons (BPCs) have emerged as an important class due to their unique characteristics, for instance, remarkable textural features, less expensive and abundant precursors, surface chemistry, and tunable porosity, and therefore are considered appropriate for CO2 capture under diverse conditions. Different synthetic strategies have been employed to produce suitable textural as well as physicochemical properties in BPCs to effectively use them for CO2 adsorption applications. In this review, we have comprehensively discussed the origin and compositional analysis of biomass, its conversion strategies (e.g., pyrolysis, hydrothermal carbonization, physical or chemical activation, and sol–gel process), non-functionalized and functionalized BPCs as CO2 adsorbents, the role of heteroatom, for instance, nitrogen, oxygen, and sulfur on BPC's textural features and CO2 adsorption performance, the mechanism behind CO2 capture (either physisorption or chemisorption), a brief note on the main approaches for CO2 capture (e.g., pre-combustion, post-combustion, and oxy-combustion), leading factors that could influence the CO2 adsorption performance of BPCs (role of higher carbon content, processing temperature and time, activating agent and impregnation ratio, etc.), and current major challenges. Finally, a summary is provided that discusses concluding remarks and future research directions with possible solutions for the effective development of BPCs to seek excellent CO2 capture and conversion applications. [ABSTRACT FROM AUTHOR]

Nanoporous carbons were prepared via chemical and physical activation from mangosteen-peel-derived chars. The removal of atrazine was studied due to the bifunctionality of the N groups. Pseudo-first-order, pseudo-second-order, and intraparticle pore diffusion kinetic models were analyzed. Adsorption isotherms were also analyzed according to the Langmuir and Freundlich models. The obtained results were compared against two commercially activated carbons with comparable surface chemistry and porosimetry. The highest uptake was found for carbons with higher content of basic surface groups. The role of the oxygen-containing groups in the removal of atrazine was estimated experimentally using the surface density. The results were compared with the adsorption energy of atrazine theoretically estimated on pristine and functionalized graphene with different oxygen groups using periodic DFT methods. The energy of adsorption followed the same trend observed experimentally, namely the more basic the pH, the more favored the adsorption of atrazine. Micropores played an important role in the uptake of atrazine at low concentrations, but the presence of mesoporous was also required to inhibit the pore mass diffusion limitations. The present work contributes to the understanding of the interactions between triazine-based pollutants and the surface functional groups on nanoporous carbons in the liquid–solid interface. [ABSTRACT FROM AUTHOR]

In the presented research, activated carbons from wheat bran were obtained as a result of pyrolysis and physical activation (CO2 or/and steam). In addition, the obtained materials were subjected to additional modification with superheated steam using the microwave radiation as an energy source. The detailed materials characterization was performed using low-temperature nitrogen adsorption/desorption, Raman spectroscopy, X-ray diffraction, thermal analysis (TG), Boehm's titration, point of zero charge (pHpzc), scanning electron microscopy (SEM) and FT-IR/ATR methods. Moreover, the sorption capacity towards methylene blue (MB) was determined. The activated carbons were characterized with a well-developed surface and pore structure (SBET = 339.6–594.0 m2/g; Vp = 0.157–0.356 cm3/g). Activation in the presence of steam and additional modification with microwave radiation resulted in much better development of the porous structure (SBET = 600.4 m2/g; Vp = 0.380 cm3/g). The materials were shown to possess amorphous structure and thermal stability up to the temperatures of ~450–500 °C. They have good adsorption capacity towards MB varying from 150 mg/g to 241 mg/g depending on activation manner. The adsorption can be described by the pseudo-second order model (R2 = 0.99) and fitted to the Langmuir isotherm. [ABSTRACT FROM AUTHOR]

Droplet impact and breakup on meshes are relevant to a number of applications involving filters, textiles, and other spatially inhomogeneous media encountering gas‐dispersed liquids. This study presents high‐resolution simulation results of mm‐size droplets striking wettability‐patterned meshes with the goal of (a) replicating prior physical experiments, (b) identifying sensitivities to the initial conditions and wettability of the mesh wires, and (c) studying the fluid‐field dynamics when droplets strike such meshes. The insights from the present model may help to advance understanding of droplet atomization on meshes, which depends on a number of parameters that are nontrivial to control in an experimental setting. The analysis is carried out by benchmarking the numerical methods used in a commercial software package for orthogonal droplet impact on a flat smooth surface, followed by a convergence analysis, and finally, simulation of specific experiments and case studies involving wettability‐patterned mesh targets. We show that the wettability contrast between the hydrophilic and hydrophobic domains on the mesh as well as the contact angle hysteresis on each side play a critical role in determining whether liquid pinch‐off occurs. The three‐dimensional computational framework constructed in this work is a step toward predicting the postimpact behavior of droplets that strike woven meshes and other porous inhomogeneous media consisting of materials with different wetting properties. [ABSTRACT FROM AUTHOR]

This work studies the removal of o-cresol from wastewater by using ozonation followed by adsorption onto sodium natural bentonite (Na-Bent). The degradation of o-cresol was followed by UV-Vis. During ozonation, 2-methylbenzoquinone (2-mBQ) and 2-methylhydroquinone (2-mHQ) were identified as two of the main by-products, while the pH decrease suggested the breakage of aromatic compounds into smaller organic acids. After 30 min treatment, the o-cresol degradation for 250–62.5 mg/L solutions was found between 64–85%, respectively. Next, the wastewater containing persistent o-cresol and by-products was contacted with Na-Bent adsorbent. The solutions and physicochemical properties of Na-Bent were analysed, before and after adsorption, by UV-Vis, FTIR, XRD and N2 adsorption-desorption. Moreover, equilibrium and kinetic experiments were carried out to study the adsorptive properties of the Na-Bent. While sole ozonation or adsorption failed on the remediation of o-cresol solutions, the obtained results show that the contact of ozonated solutions with Na-Bent led to almost total removal of the o-cresol initial concentrations (between 96% and 99%). This excellent performance is assigned to the high volume of interlayer micropores and the suitable surface chemistry of this natural adsorbent. [ABSTRACT FROM AUTHOR]

The adsorption and photocatalytic degradation of trimethyl phosphate (TMP) and triethyl phosphate (TEP), two environmentally relevant model pollutants, have been studied on commercial anatase TiO2 and sulfate-terminated anatase TiO2 nanoparticles by means of operando diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy and 2D correlation spectroscopy (2D COS). It is concluded that both TMP and TEP adsorb dissociatively on anatase TiO2, while on the sulfate-terminated anatase TiO2, TMP and TEP adsorb associatively. Upon UV illumination, TMP and TEP are completely oxidized on sulfate-terminated anatase TiO2, as evidenced by the evolution of the IR bands characteristic for water and carbon dioxide. In contrast, on anatase TiO2, UV illumination leads to the formation of stable surface-coordinated carboxylate products, which impedes complete oxidation. 2D COS analysis suggests that parallel reaction pathways occur during oxidation under UV illumination, viz. methoxide/ethoxide (ads) → carboxylates (ads) and methoxide/ethoxide (ads) → aldehydes (ads) → carboxylates (ads). A parallel reaction occurs on sulfated TiO2 that yields CO2 and H2O by direct radical reactions with the methoxide groups with little, or no, formation of surface-coordinated intermediates. Sulfated TiO2 favor the formation of aldehyde intermediates, with reaction rates 10 times and 30 times faster for TMP and TEM, respectively, compared with commercial anatase TiO2. About 37% (33%) and 32% (24%) of TMP (TEP) were degraded on sulfated-terminated TiO2 and pure TiO2, respectively, after the first 9 min of UV illumination. We show that the sulfate-functionalization of TiO2 has two main functions. First, it prevents the formation of strongly bonded bridging carboxylates, thereby alleviating deactivation. Second, it promotes full oxidation of the organic side-chains into carbon dioxide and water. Improved electron-hole separation by the electrophilic S(VI) in combination with the blocking of bridging reaction intermediates is proposed to contribute to the improved activity. The presented results give insights into how acidic surface modifications change adsorbate surface chemistries, which can be used to increase the sustained activity of low-temperature photocatalysts. [ABSTRACT FROM AUTHOR]

Silica aerogels are a class of materials that can be tailored in terms of their final properties and surface chemistry. They can be synthesized with specific features to be used as adsorbents, resulting in improved performance for wastewater pollutants' removal. The purpose of this research was to investigate the effect of amino functionalization and the addition of carbon nanostructures to silica aerogels made from methyltrimethoxysilane (MTMS) on their removal capacities for various contaminants in aqueous solutions. The MTMS-based aerogels successfully removed various organic compounds and drugs, achieving adsorption capacities of 170 mg⋅g−1 for toluene and 200 mg⋅g−1 for xylene. For initial concentrations up to 50 mg⋅L−1, removals greater than 71% were obtained for amoxicillin, and superior to 96% for naproxen. The addition of a co-precursor containing amine groups and/or carbon nanomaterials was proven to be a valuable tool in the development of new adsorbents by altering the aerogels' properties and enhancing their adsorption capacities. Therefore, this work demonstrates the potential of these materials as an alternative to industrial sorbents due to their high and fast removal efficiency, less than 60 min for the organic compounds, towards different types of pollutants. [ABSTRACT FROM AUTHOR]

The importance of the textural and physicochemical characteristics upon the adsorption capacity of the commercial activated carbons (ACs) Coconut, Wood, Merck, Darco, and Norit towards ronidazole (RNZ) and diclofenac (DCF) from water solution was investigated thoroughly in this work. At pH = 7, Coconut AC and Wood AC presented the highest adsorption capacity towards RNZ (444 mg/g) and DCF (405 mg/g). The maximum mass of RNZ adsorbed onto Coconut AC was higher in this study than those outlined previously in other works. Besides, the maximum capacity of Wood AC for adsorbing DCF was comparable to those found for other ACs. The adsorption capacity of all the ACs was increased by surface area and was favored by incrementing the acidic site concentration. The π-π stacking interactions were the predominant adsorption mechanism for the RNZ and DCF adsorption on ACs, and the acidic sites favored the adsorption capacity by activating the π-π stacking. Electrostatic interactions did not influence the adsorption of RNZ on Coconut AC, but electrostatic repulsion decreased that of DCF on Wood AC. The adsorption of DCF on Wood AC was reversible but not that of RNZ on Coconut AC. Besides, the adsorption of RNZ and DCF on the Coconut and Wood ACs was endothermic in the range of 15–25 °C. [ABSTRACT FROM AUTHOR]

The widespread use of nanomaterials in vaccines, therapeutics, and industrial applications creates an increasing demand for understanding their ingestion by living cells. Researchers in the field have called for a more robust understanding of physical/chemical particle–cell interactions and a means to determine the particles ingested per cell. Using superparamagnetic nanobeads, we measured the beads per cell and quantified the kinetics of the receptor-independent endocytosis of particles having seven surface chemistries. Poly(ethylene glycol) (PEG)-coated nanoparticles were ingested less effectively by cultured Chinese hamster ovary (CHO-K1) cells and more effectively by aminated nanoparticles than starch-coated particles. The cells ingested 2 to 4 × 105 of the most attractive particles. The interplay between Van der Waals and coulombic potentials was quantified on the basis of Derjaguin–Landau–Verwey–Overbeek (DLVO) theory modified to include hydration repulsion using physical parameters of the seven surface chemistries. Using dose–response curves for inhibitors of clathrin- or caveolae-dependent ingestion, we quantified how particle surface chemistry determines which endocytic pathway is used by the cell. Such characterization can be useful in predicting nanomaterial uptake in medical and toxicological applications and in the selection of particle surface chemistries for receptor-dependent endocytosis. [ABSTRACT FROM AUTHOR]

Sorption on activated carbon (AC) are the most widely used method for deep extraction of synthetic aromatic organic compounds from their aqueous solutions. To achieve maximum efficiency, it is necessary to correctly select the adsorbent by taking into account its structural and sorption characteristics and surface chemistry, as well as the size of molecules of the pollutant and their ability to ionize in a solution at a certain pH value. In this study, the equilibrium adsorption extraction of phenol under static conditions by commercial sorbents with different physicochemical characteristics (Sibunit, KAD, Akant, F300, and KAU) is investigated. Room temperature adsorption isotherms at a dissolved oxygen concentration of 5–6 mg/dm3 and pH = 5.2–7.2 are studied. The effects of the porosity and the nature and number of surface active sites of AC on the efficiency of phenol adsorption from dilute aqueous solutions are studied. It is shown that the small concentrations of surface active sites of the studied commercial sorbents have no substantial effect on the efficiency of purifying aqueous solutions from phenol, but structural and sorption characteristics—in particular, the volume of the narrowest but accessible micropores—have the greatest effect. Among the studied ACs, sorbents Akant, F300, and KAU have such characteristics. [ABSTRACT FROM AUTHOR]

The use of green and effective inhibitors for preventing metal oxide (MgO) corrosion in industrial applications is highly significant in promoting environmental protection and sustainable development. This study delves into the adsorption behavior and interfacial mechanism of environmentally friendly inhibitor derived from propane hydrazine (PH) on MgO surface. Specifically, PH1, PH2, PH3, and PH4 were explored for their effectiveness in preventing corrosion by using advanced theoretical simulations-based density functional theory (DFT) for assessing the reactivity and adsorption characteristics. The study considered a detailed exploration of local and global reactivity descriptors, providing insights into the inhibitors' reactivity and adsorption abilities in both isolated and adsorbed states. These findings focus more in the mechanisms underlying organic-inorganic interactions and present promising prospects for further development and application. Using first-principles DFT calculations alongside quantitative molecular surface analyses, we examined the adsorption patterns of PHs on the MgO(100) surface. These investigations are boosted by the application of independent gradient model (IGM) framework, providing robust verification of PHs' adsorption behavior on MgO(100) surface. Our calculations reveal a substantial decrease in the energy gap following complex formation, suggesting that charge density changes occur upon interaction with MgO surfaces, thereby facilitating direct electron transfer in all the studied systems. Noreover, the results highlight the crucial role of intermolecular interactions in boosting the interaction between PHs and the [Mg(H 2 O) 6 ]2+ cation. First-principles DFT calculations show that all PH molecules consistently display parallel adsorption on the MgO surface, where the oxygen atoms form bonds with adjacent magnesium atoms. The bond lengths vary from 2.18 to 2.35 Å when PHs bind to the Mg atoms in parallel orientations through the oxygen atom, suggesting a stable parallel arrangement for PH molecules on the MgO surface. The calculated adsorption energy (E ads) varies in the following order: MgO-PH3 (−815.14 Kcal mol−1) > MgO-PH2 (−803.85 Kcal mol−1)) > MgO-PH4 (−695.38 Kcal mol−1) > MgO-PH1 (−125.77 Kcal mol−1). This trend indicates that parallel interactions enhance the adsorption behavior and binding of PH compounds through inter- and intra-molecular interactions, resulting in the PHs being centered at specific sites on the MgO surface. The potential enhancement in electrochemical properties is believed to stem from the synergistic interaction between the PHs and the MgO surface, which theoretically allows for a precise adjustment of their adsorption and interaction within the composite structure. This understanding provides a fundamental framework for examining the complex interfacial dynamics between inhibitor structures and elucidating how these molecular interactions influence the selection of corrosion inhibitors and their adsorption behaviors on the corrosion layer's surface, rather than on metallic Mg. [Display omitted] • DFT calculations evaluated the adsorption characteristics of four PHs molecules. • Adsorption capability of PHs in both isolated and adsorbed states are evaluated. • Quantitative analyses and IGM are used to reveal the inter-/intra- molecular interactions. • PHs-MgO interactions deepen understanding of surface chemistry and adsorption. [ABSTRACT FROM AUTHOR]

• Small molecule interactions with monolayers, thin films, and bulk Cu 2 O are reviewed. • Monolayer Cu 2 O films are better models for oxidized metallic copper rather than Cu 2 O. • Cu 2 O single crystals are ideal for fundamental reactivity studies. • The prospect of using Cu 2 O as a support for single atom catalysts is presented. The chemical and electronic properties of copper combined with its large natural abundance lend this material to impact a wide range of technological applications, including heterogeneous catalysis. The reactivity of copper in its Cu1+oxidation state makes this specific configuration relevant in various chemical reactions, but the facile redox properties of copper make the isolation of individual states for fundamental studies difficult. Here we review three Cu 2 O model systems used to study the interaction of Cu1+ with small molecules making use of surface science techniques: Cu 2 O/Cu(111), thin polycrystalline Cu 2 O films on Cu foil, and bulk Cu 2 O crystals. Advantages and disadvantages of each system are discussed and exemplified through case studies of chemical adsorption and reactivity studies. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Surface chemistry of activated carbon (AC) controls the adsorption of PFAS. • The degree of surface acidity is negatively correlated with PFAS uptake. • Basic and hydrophobic AC surfaces are favorable for PFAS adsorption. • PFAS structure minimally impacts adsorption to basic and hydrophobic AC surfaces. • At least four mechanisms are involved in PFAS adsorption to carbon-based surfaces. Using activated carbon (AC) to adsorb per- and polyfluoroalkyl substances (PFAS) is highly practical for environmental remediation. However, examining the surface chemistry of carbonaceous material with regard to the removal of various PFAS has been limited, as the focus has often solely been on perfluorooctanoic acid and perfluorooctane sulfonic acid. Consequently, this study systematically explores the role of AC surface chemistry in the adsorption of PFAS with various structural properties using ACs that have been modified for different degrees of acidity, basicity, and hydrophobicity. Batch adsorption studies have demonstrated that the affinity of PFAS for the AC surface is negatively correlated with surface acidity. The removal performance at an adsorbent dose of 2 mg/L and an initial PFAS concentration of 600 ng/L is 27.4–91.4 %, 57.2–95.6 %, 92.4–99.2 %, and 89.1–99.6 % for an AC with an acidic surface, unmodified AC, defunctionalized AC, and AC with basic surface, respectively. Analyses of the adsorption isotherms, kinetics, and removal performance of the four types of ACs and 14 PFAS in water at different pH and ionic strengths reveal that hydrophobic, electron donor–acceptor, and electrostatic interactions, as well as negative charge-assisted hydrogen bond formation are necessary to describe the key adsorption characteristics observed in the experiments. The relative significance of the adsorption mechanisms depends on the PFAS structural properties, AC surface chemistry, and water composition. This extensive discourse contributes substantially to the design of an efficient carbonaceous adsorbent with specific surface moieties for removing PFAS from water. [ABSTRACT FROM AUTHOR]

Layered double hydroxides (LDHs) have emerged as an effective ingredient for enhancing the durability of cement-based materials against chloride-contaminated coastal or marine environments. Yet, the relationship between the surface chemistry and consequential adsorption affinity, which mainly constitutes chloride binding capacity of LDHs, still remain elusive, especially in alkaline cement pore solutions. Herein, we investigate Mg-Al-CO 3 -LDHs to demonstrate the cationic-ratio- (MII/MIII-) regulated surface chloride adsorption in alkaline solutions through a series of progressively in-depth means. The regulatory mechanism of the cationic ratio is microscopically operated through diverse composition and proportion of hydroxylated clusters with varying deprotonation reactivity of bonded hydroxyl on the surface. DFT calculations combined with multiple surface characterization techniques indicate that the varying reactivity is determined by the ionic bonding characteristics of H O bond and the electrostatic attraction ability of different clusters. The LDH with Mg/Al ratio of 2.0 exhibits the optimal surface chloride adsorption among ratios ranging from 1.6 to 3.8 in alkaline solutions due to the strong resistance to nucleophilic attack from OH− of Mg 2 Al-OH cluster while maintaining high electrostatic attraction ability. Our findings advance the comprehension of surface interactions of LDHs with alkaline environments while underscoring the role of cationic ratio in surface chloride adsorption. [ABSTRACT FROM AUTHOR]

There have been several reports of the enantiospecific adsorption of chiral compounds from solution onto ferromagnetic surfaces in applied magnetic fields. This work studies the kinetics of D‐ and L‐aspartic acid (Asp) adsorption onto a Ni(100) surface in a 0.45 T applied magnetic field under ultra‐high vacuum (UHV) conditions. Desorption studies performed after exposing the Ni(100) sample to L‐Asp revealed no influence of the applied magnetic field on the adsorption kinetics. Similarly, concurrent exposure of the Ni(100) surface to a mixture of isotopically labeled L*‐Asp and D‐Asp resulted in no detectable field induced differences in the relative enantiomer coverages adsorbed onto the surface. In summary, the presence of an applied magnetic field had no detectable influence on the adsorption kinetics of Asp enantiomers on a Ni(100) surface under UHV conditions. This is in contrast to the magnetic field induced adsorption enantiospecificity observed in solution phase. The possible origins of this discrepancy are considered. [ABSTRACT FROM AUTHOR]

In this review, several adsorbents were studied for the elimination of heavy metal ions from multi-component wastewaters. These utilized sorbents are mineral materials, microbes, waste materials, and polymers. It was attempted to probe the structure and chemistry characteristics such as surface morphology, main functional groups, participated elements, surface area, and the adsorbent charges by SEM, FTIR, EDX, and BET tests. The uptake efficiency for metal ions, reusability studies, isotherm models, and kinetic relations for recognizing the adsorbent potentials. Besides, the influential factors such as acidity, initial concentration, time, and heat degree were investigated for selecting the optimum operating conditions in each of the adsorbents. According to the results, polymers especially chitosan, have displayed a higher adsorption capacity relative to the other common adsorbents owing to the excellent surface area and more functional groups such as amine, hydroxyl, and carboxyl species. The high surface area generates the possible active sites for trapping the particles, and the more effective functional groups can complex more metal ions from the polluted water. Also, it was observed that the uptake capacity of each metal ion in the multi-component solutions was different because the ionic radii of each metal ion were different, which influence the competition of metal ions for filling the active sites. Finally, the reusability of the polymers was suitable, because they can use several cycles which proves the economic aspect of the polymers as the adsorbent. [ABSTRACT FROM AUTHOR]

The carbon black N-220 surface was subjected to modification through H2O2 oxidation and deposition of aminopropyltriethoxysilane. The pristine (CB-NM) and modified materials (CB-Ox and CB-APTES) were characterized by N2 adsorption–desorption isotherms, scanning electron microscopy, energy-dispersive X-ray spectroscopy (SEM-EDS), thermogravimetry, and FTIR spectroscopy. Carbon black samples were applied as adsorbents for the removal of 2,4-dichlorophenoxyacetic acid (2,4-D) and 2-methyl-4-chlorophenoxyacetic acid (MCPA) herbicides from aqueous solutions. The influence of their surface properties on adsorption efficiency was analyzed and discussed. The results showed that the adsorption of the herbicides was pH-dependent, and the most favorable adsorption was observed in an acidic environment. The experimental data best fit pseudo-second-order and Langmuir models for kinetic and equilibrium data, respectively. The adsorption rate of both the herbicides increased in the order of CB-APTES < CB-Ox < CB-NM and was closely correlated with the mesopore volume of the carbon blacks. The monolayer adsorption capacities were found to be 0.138, 0.340, and 0.124 mmol/g for the adsorption of 2,4-D and 0.181, 0.348, and 0.139 mmol/g for the adsorption of MCPA on CB-NM, CB-APTES, and CB-Ox, respectively. The results showed that the surface chemistry of the adsorbent plays a more important role than its porous structure. Both herbicides were preferably adsorbed on APTES-modified carbon black and were adsorbed the worst on oxidized carbon black (CB-APTES > CB-NM > CB-Ox). [ABSTRACT FROM AUTHOR]

In this study, an optimized composite of expanded graphite/g-C3N4/phenylenediamine was synthesized and characterized by SEM, FESEM, EDS, XRD, and BET methods. The composite was prepared with an optimized combination using response surface methodology (RSM) as a proper adsorbent for eliminating heavy metals from water samples. The evaluation of the final adsorbent was accomplished by removing metal ions like Pb2+ and Cd2+. Under the optimum adsorption conditions for Pb2+ and Cd2+ (pH:5, adsorbent dosage:2 g/L, and Time:60 min), elimination efficiencies were 78.4% for Cd2+ and 71.35% for Pb2+. pH was the most important factor that influenced the adsorption rate. A short contact time for maximum removal efficiency was reported because of the porous structure of the constructed composite. As a result of the absorptive construction, the equilibrium showed a satisfactory agreement with the Freundlich model. The kinetic evaluations showed that the adsorption process of both heavy metals fitted the pseudosecond-order model. Furthermore, the results of thermodynamic studies indicated that the adsorption was an endothermic and spontaneous process. A series of regeneration experiments (5 cycles) was directed to evaluate the adsorbent reusability. The results presented that it was a suitable adsorbent for heavy metal uptake from aquatic solutions. [ABSTRACT FROM AUTHOR]

Lead ion (Pb2+) in wastewater cannot be biodegraded and destroyed. It can easily be enriched in living organisms, which causes serious harm to the environment and human health. Among the existing treatment technologies, adsorption is a green and efficient way to treat heavy metal contamination. Novel KMnO4-treated magnetic biochar (KFBC) was successfully synthesized by the addition of Fe(NO3)3 and KMnO4 treatment during carbonization following Pb2+ adsorption. SEM-EDS, XPS, and ICP-OES were used to evaluate the KFBC and magnetic biochar (FBC) on the surface morphology, surface chemistry characteristics, surface functional groups, and Pb2+ adsorption behavior. The effects of pH on the Pb2+ solution, initial concentration of Pb2+, adsorption time, and influencing ions on the adsorption amount of Pb2+ were examined, and the adsorption mechanisms of FBC and KFBC on Pb2+ were investigated. The results showed that pH had a strong influence on the adsorption of KFBC and the optimum adsorption pH was 5. The saturation adsorption capacity fitted by the model was 170.668 mg/g. The successful loading of manganese oxides and the enhanced oxygen functional groups, as evidenced by XPS and FTIR data, improved KFBC for heavy metal adsorption. Mineral precipitation, functional group complexation, and π-electron interactions were the primary adsorption processes. [ABSTRACT FROM AUTHOR]

The influence of the geometric modification (GM) of fumed nanoscale silica A300 (NS) on the adsorption capacity of human serum albumin (HSA) as well as the physicochemical and textural properties of the protein/nanosilica system was analyzed. An effective medical enterosorbent based on fumed nanosilica was designed and produced in the Chuiko Institute of Surface Chemistry, National Academy of Sciences of Ukraine. To design an effective nanomaterial for biomedical applications as a wound-healing material, the adsorption, physicochemical and surface properties of the initial nanosilica (NS), nanosilica after geometric modification (GM-nanosilica), and HSA/nanosilica biocomposites were characterized. The differences in sorption capacities, acid-base, textural, and surface properties of the obtained materials were monitored using the diffuse UV–vis reflectance spectroscopy, the potentiometric titration of suspension, the nitrogen adsorption/desorption isotherms, the scanning electron microscopy with the energy dispersive X-ray microanalysis and the digital optical microscope. For a deeper understanding of the nature of immobilized HSA molecules on the nanosilica and GM-nanosilica, the surface functional groups were characterized by the FTIR spectroscopy. It was found that the adsorption properties, physicochemical and textural characteristics of fumed nanoscale silica depend on the mechanical treatment time (t MT) and bulk density (d b). In fact, as the t MT increases, the d b of initial fumed nanosilica increases, and the protein adsorption capacity decreases, however, it remains at an acceptable level: 0.075 g/g, 0.056 g/g, 0.032 g/g for GM-nanosilica after 1, 4, and 7 h of mechanical treatment, respectively. HSA adsorption significantly changes the surface morphology, acid-base character, and structure of both unmodified and modified nanosilica. [Display omitted] • Mechanical treatment leads to significant changes in enterosorbents bulk density. • Methods for the production of fumed silica based bionanocomposites have been developed. • Decrease of protein adsorption with an increased nanosilica bulk density observed. • Physicochemical properties change of biocomposites HSA/NS and HSA/GM-nanosilica. • Topography, nanostructure, chemical composition of HSA/nanosilica surface analyzed. [ABSTRACT FROM AUTHOR]

[Display omitted] Graphene-based microparticles materials are broadly utilized in all sorts of fields owing to their outstanding properties. Despite great progress, the present graphene microparticles still face challenges in the aspects of size uniformity, motion flexibility, and tailorable surface chemistry, which limit their application in some specific fields, such as versatile adsorption. Hence, the development of novel graphene microparticles with the aforementioned characteristics is urgently required. We presented a simple microfluidic electrospray strategy to generate magnetic Janus reduced graphene oxide/carbon (rGO/C) composite microspheres with a variety of unique features. Specifically, the microfluidic electrospray method endowed the obtaiend microspheres with sufficient size uniformity as well as magnetic responsive motion ability. Additionally, magnetic-mediated surface assembly of phase transition lysozyme (PTL) nanofilm on the microspheres rendered the deposited area hydrophilic while non-deposited area hydrophobic. Such magnetic Janus rGO/C composite microspheres with regionalized wettability characteristics not only showed prominent performance in adsorbing organic liquids with high adsorption capacity and remarkable reusability but also displayed satisfying biocompatibility for the efficient uptake of bilirubin. More encouragingly, the microspheres could serve as adsorbents in a simulative hemoperfusion setup, which further demonstrated the clinical application potential of the magnetic Janus rGO/C microspheres. Thus, we anticipate that the obtained magnetic Janus rGO/C composite microspheres could show multifunctional properties toward water treatment and blood molecule cleaning. [ABSTRACT FROM AUTHOR]

In this study, three different types of biochar (biomass materials were beech wood, corncob, and bamboo) were loaded with bismuth to form bismuth impregnated biochars (named respectively as Bi@WBC, Bi@CBC, and Bi@BBC) to investigate their properties (pore structure and surface chemistry characteristics) on methylene blue (MB) removal capacities. Three bismuth impregnated biochars made from different biomass materials were ranked for their adsorption capacity of MB as follows: Bi@WBC > Bi@CBC > Bi@BBC, in which Bi@WBC showed the largest Langmuir adsorption capacity of 178.59 mg g−1. While the specific surface area (SSA) and pore volume of Bi@WBC were the largest (accounting for 477.74 m2 g−1 and 0.15 cm3 g−1, respectively), according to the FTIR and XPS results, Bi@WBC (72.3%) exhibited a higher proportion of BiO bonds than the Bi@CBC (52.3%) and Bi@BBC (48.4%) did. Conclusively, the rich porous structure and surface functional groups of Bi@WBC affected the adsorption capacity of MB, and the chemical adsorption provided the main contribution. © 2022 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOF) are a new type of porous materials that have great potential for adsorption of voltaic organic compounds (VOCs). These types of materials composed of metal ions and organic ligands are easy to synthesize, have high surface areas, their surface chemistry can be adjusted to the desired application, and they can also have good chemical and thermal stability. Therefore, this work focuses on the synthesis of a highly hydrophobic MOF material called CIM-80, a porous material that is made up of the Al3+ cation and the mesaconate linker. This MOF has a B.E.T. of approximately 800 m2/g and has potential applications for the adsorption of hydrophobic organic compounds. However, its synthesis is expensive and very dirty. Therefore, we have studied the synthesis conditions necessary to achieve high synthesis yields (85%) and materials with high crystallinity and accessible porosity. To achieve these results, we have used urea as a mild deprotonation reagent and modulator as an alternative to NaOH, which is traditionally used for the synthesis of this MOF. Once the synthesis of this material was controlled, its adsorption/desorption behavior of water and organic compounds such as toluene, cyclohexane and m-xylene was studied by means of vapor adsorption isotherms. The results show the hydrophobic character of the material and the greater affinity the material has toward aliphatic compounds than toward aromatic ones, with toluene being the most adsorbed compound, followed by cyclohexane and m-xylene. [ABSTRACT FROM AUTHOR]