In this study, ZnAl layered double hydroxide (LDH) nanocontainers were grown in situ on AA2024 aluminum alloy through a controlled hydrothermal process, using the native oxide layer as an internal aluminum source, and succinic acid (SA) and tartaric acid (TA) inhibitor anions were subsequently intercalated into the LDH interlayers via an optimized ion-exchange treatment performed at 60 °C under ambient pressure, with exposure times from 15 min to 5 h to evaluate the effect of intercalation duration on inhibitor uptake and film stability. Structural and morphological analyses by X-ray diffraction (XRD) and scanning electron microscopy (SEM) confirmed the formation of well-crystallized LDH films and the successful incorporation of the organic inhibitors. Corrosion resistance in 3.5% NaCl, assessed through immersion tests, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization (PDP), showed that the SA-intercalated coating achieved an inhibition efficiency of 95.1% after 48 h, significantly higher than the 62.5% obtained for the TA-based coating, while the pristine LDH layer provided only short-term barrier protection. The superior performance of LDH_SA is attributed to the synergistic effects of chloride ion trapping within the LDH matrix, the formation of a hydrophobic protective layer generated by released SA, and a self-healing response driven by ion-exchange mechanisms. Density functional theory (DFT) and Monte Carlo (MC) simulations further revealed strong physisorption and chemisorption interactions between the inhibitors and both the LDH surface and the aluminum substrate, and the combined experimental-theoretical results demonstrate that LDH_SA constitutes a robust, environmentally friendly, and highly efficient corrosion-mitigation coating for aluminum alloys in chloride-rich environments.

Efficient removal of synthetic dyes from wastewater is crucial to mitigate their environmental impact. In this study, MgAl-layered double hydroxides (MgAl LDHs) with Mg²⁺:Al³⁺ ratios of 2:1, 3:1, and 4:1 and two interlayer anions (Cl⁻ and CO₃²⁻) were synthesized by co-precipitation and characterized by XRD, FTIR, BET, SEM, and TEM. Batch adsorption experiments optimized key variables, with best performance at pH 5, 120 min contact time, and 0.02 g adsorbent dosage. The Mg₃Al–Cl sample showed the highest capacities–even when both dyes were present and interfering with each other–reaching 166.62 mg·g⁻¹ for methyl orange (MO) and 123.35 mg·g⁻¹ for congo red (CR). Kinetic data were best described by the pseudo-second-order model, and isotherms fitted the Langmuir equation. Thermodynamic parameters indicated a feasible, spontaneous, and endothermic process. The interlayer anion critically affected performance: chloride-intercalated LDHs outperformed carbonate-intercalated ones under identical conditions, consistent with differences in anion exchange and interaction strength with the galleries. The material retained >80 % capacity after five regeneration cycles. Density functional theory (DFT) supported the experiments, showing adsorption governed by electrostatic attraction, hydrogen bonding, surface complexation, and n–π stacking, and clarifying how both the Mg²⁺:Al³⁺ ratio and the interlayer anion identity tune adsorption efficiency. The originality of this work lies in a combined experimental–DFT framework that co-optimizes cation ratio and interlayer anion to predict and enhance simultaneous removal of multiple anionic dyes.

This work presents an active corrosion protection system for AA7075 based on a TEOS/GPTMS-derived hybrid sol-gel coating doped with ZnAl layered double hydroxides (ZnAl-LDH) intercalated with fumaric acid (FA) as a green corrosion inhibitor. The incorporation of FA-loaded ZnAl-LDH nanocontainers combines both passive barrier protection and active, inhibitor-driven corrosion control. Structural, morphological, and colloidal analyses confirm successful FA intercalation, homogeneous LDH dispersion, and stable embedding within the sol-gel matrix. The anticorrosion performance of SG, SG/ZnAl-LDH, and SG/ZnAl-LDH/FA coatings was assessed using salt spray testing (SST) and electrochemical impedance spectroscopy (EIS) in 3.5 wt% NaCl. The SG/ZnAl-LDH/ FA system exhibits significantly enhanced long-term corrosion resistance compared to undoped and inhibitorfree coatings, as evidenced by higher coating and charge-transfer resistances (Rcoat and Rct) together with relatively stable interfacial capacitive responses (Qcoat and Qdl), as well as sustained oxide/interphase parameters (Qox and Rox) indicating improved interfacial stability during immersion. This improved performance is attributed to the synergistic barrier effect of the sol-gel matrix and LDH platelets, along with the chloride-responsive release of FA triggered in chloride-containing environments. The LDH nanocontainers act both as physical diffusion barriers and anion-exchange hosts for corrosion inhibitor delivery, enabling a stimuli-responsive corrosion inhibition mechanism. Density functional theory (DFT) calculations support the stabilization of FA within the LDH structure and its favorable interaction with aluminum surface sites, providing molecular-level insight into the experimentally observed corrosion protection mechanism. This environmentally friendly coating strategy offers a promising route for advanced corrosion protection of aluminum alloys.

Understanding the structure-property relationships governing organic-inorganic layered materials is essential for the rational design of functional hybrid systems. In this work, gallic acid (GA) was incorporated into MgAl and ZnAl layered double hydroxides (LDHs), in both pristine and calcined forms, using co-precipitation and anion-exchange routes. The study aims to elucidate how the nature of the metal cations and the incorporation strategy influence the structural organization, interfacial interactions, and physicochemical properties of GA-LDH hybrids. X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy confirmed successful gallic acid intercalation, accompanied by controlled modifications of the interlayer spacing and hydrogen-bonding environment while preserving the layered framework. Scanning and transmission electron microscopy (SEM and TEM) revealed synthesis-dependent morphological features and particle organization. The GA-LDH hybrids exhibited pronounced composition-dependent antioxidant and antimicrobial activities, which are directly correlated with differences in GA confinement, interlayer interactions, and release behavior. pH-responsive release studies further demonstrated the role of host-guest interactions and layer reconstruction in governing molecular accessibility. Biocompatibility assessments indicated that GA incorporation does not induce adverse cellular responses. To provide molecular-level understanding, density functional theory (DFT) calculations were employed to analyze GA-LDH interactions, revealing that electrostatic forces, hydrogen bonding, pi-pi interactions, and metal coordination collectively stabilize the hybrids and regulate GA release. These findings establish clear links between LDH composition, interfacial chemistry, and the multifunctional properties of GA-intercalated layered materials.

A novel organonacrite-based electrochemical sensor was developed for highly sensitive and selective detection of trace cadmium ions (cadmium(II), Cd2+) in aqueous media. The hybrid material, nacrite-octadecylamine (Nac-ODA), was prepared by intercalating octadecylamine (ODA) into the interlayer spaces of natural nacrite. Comprehensive physicochemical characterization using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and N2 adsorption-desorption isotherms (Brunauer-Emmett-Teller, BET) confirmed successful organo-functionalization, interlayer expansion, and a significant increase in specific surface area, features favorable for analyte interaction. The Nac-ODA composite was used to modify a glassy carbon electrode (GCE), and its electrochemical behavior was investigated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), confirming effective surface modification. Square wave voltammetry (SWV) enabled quantitative detection, achieving a detection limit (LOD) of 0.145 ppb and a quantification limit (LOQ) of 0.483 ppb within a range of 5 to 50 ppb at pH 5.0. The sensor exhibited excellent reproducibility, high selectivity in the presence of common interfering ions, stable response over repeated daily cycles, and reliable performance in real samples. To rationalize the experimental findings, complementary density functional theory (DFT) calculations were also performed to model the Nac-ODA surface, optimize its interaction geometry with Cd2+, and quantify the associated adsorption energies. The theoretical results elucidated the binding mechanism at the atomic scale, revealing energetically favorable, coordination-driven adsorption dominated by electrostatic and donor-acceptor interactions, which supports the enhanced electrochemical performance observed experimentally. Development of a highly sensitive and selective Cd2+ electrochemical sensor based on Nacrite-ODA modified GCE.Comprehensive physicochemical characterization confirms successful intercalation and surface enhancement of the organonacrite composite.SWV enables trace-level detection of Cd2+ with excellent reproducibility and real-sample applicability.DFT calculations support the experimental results, showing favorable Cd2+ adsorption dominated by electrostatic and donor-acceptor coordination.Combined experimental and theoretical approach offers valuable insight into the sensing mechanism and material-ion interactions.

This study introduces a novel approach using MgZnAl-layered triple hydroxide (LTH) and activated carbon (AC) derived from argan nutshells, designed to enhance MO and MB adsorption from aqueous solutions. Synthesized via coprecipitation, carbonization, and H3PO4 activation processes, the LTH_AC composites were thoroughly characterized using XRD, FTIR, Raman, BET, SEM, and TEM. The LTH_AC500 composite showed good adsorption capacities, achieving 154.219 mg/g for MO and 112.989 mg/g for MB. The adsorption kinetics followed a pseudo-second-order model, indicating predominant chemisorption, while the Freundlich isotherm model suggested multilayer adsorption on heterogeneous surfaces. Thermodynamic analysis confirmed the process's spontaneity, with MO adsorption being endothermic and MB adsorption exothermic. DFT theoretical studies revealed mechanisms such as it-it stacking, coordination interactions, anion exchange, and charge transfer between the dyes and the composite. Additionally, the composite demonstrated stability, recyclability over five cycles, and interference resistance, proving its potential for dye wastewater treatment.

Nanocomposites have attracted significant attention from researchers due to their remarkable chemical, adsorptive, and thermal properties. This work focuses on the synthesis of the montmorillonite modified with octadecylamine (MO):ZnO/Fe2O3 (MO:ZnO/Fe2O3) nanocomposite. The ZnO/Fe2O3 nanocomposite and MO were mixed in solution to create the component. XRD, FTIR, BET, TEM, MEB, and UV-vis were used to characterize the materials. In terms of their textural, morphological, and structural characteristics, interesting results were found. After 30 min of sunlight exposure, 96.12% of the GM dye can be degraded using just 0,02 g of MO:ZnO/Fe2O3 (1:2(1/0.05)). In contrast, ZnO NPs exhibited the highest percentage of degradation under UV light, achieving 91.85%. The greater efficiency of MO:ZnO/Fe2O3 under sunlight is attributed to its narrower band gap of 2.25 eV, which enables better utilization of visible light. Next using the Forcite and CASTEP modules in the Material Studio software, the GM dye's adsorption behavior on the surface of the as-prepared nanocomposite was analyzed. The results demonstrate that the GM/MO interaction is of the chemisorption type, predominantly governed by hydrogen bonding, electrostatic interactions, and π-π interactions between GM molecules. The ZnO (100) surface exhibits the highest density of active sites for GM degradation via a chemisorption adsorption process. Molecular dynamics simulations at 289.15 K reveal that the redox processes responsible for the degradation of the GM pollutant and its conversion into CO2 gas are exothermic. For ZnO, the electronic properties yield a band gap of 2.686 eV. For GM/ZnO (100) and GM/ZnO (101), the band gaps were determined to be 0.291 and 2.704 eV, respectively, by using a 340 eV cutoff energy and the GGA RPBE pseudofunctional.

This study investigates the anticorrosion performance of ascorbic acid (AA) intercalated into a MgAl layered double hydroxide matrix as a sustained-release system for protecting stainless steel. The AA/MgAl layered double hydroxides (LDH) composite was synthesized via the co-precipitation method, and its structural and morphological properties were characterized using X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy and nitrogen adsorption/desorption measurements. The intercalation of AA into the LDH structure enabled a controlled and sustained release, enhancing its protective effect in an aggressive acid environment. Electrochemical impedance spectroscopy revealed a significant improvement in corrosion resistance, with the inhibition efficiency converted into an equivalent release rate, reaching up to 70 % after 210 minutes of immersion in 1 M HCl. Kinetic analyses demonstrated that the release of AA followed a non-Fickian diffusion mechanism, ensuring prolonged protection. Additionally, density functional theory and Monte Carlo simulations provided insights into the adsorption mechanisms, highlighting strong interactions between AA and both the LDH matrix and the Fe steel surface. This combined experimental and theoretical approach highlights the potential of AA/MgAl LDH as an efficient, sustainable, and long-lasting corrosion inhibitor, providing a promising solution for industrial applications in harsh acidic environments.

In this work, a novel, eco-friendly composite material composed of MgAl-layered double hydroxide and cuttlebone (LDH/CB) was synthesized for the efficient adsorption of Congo Red dye from aqueous solutions. The LDH/CB composite was synthesized via a one-step co-precipitation method, and its crystallinity was confirmed by X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR). The effects of key experimental parameters—including pH, contact time, and initial dye concentration—on the adsorption efficiency were systematically investigated. The adsorption kinetics followed the pseudo-first-order model, while the equilibrium data were well described by the Langmuir and D–R isotherm, with a maximum adsorption capacity of 380 mg/g. Thermodynamic analysis revealed that the adsorption process was spontaneous, exothermic, and primarily driven by electrostatic interactions. Moreover, the composite exhibited excellent reusability over five adsorption–desorption cycles, maintaining high stability in performance. These findings highlight the potential of the LDH/CB composite as an efficient and sustainable adsorbent for the treatment of dye-contaminated wastewater.

Worsening mercury pollution necessitates the exploration of versatile materials capable of not only highly-sensitive detection of mercury ions (Hg2+) but also efficient capture and capping. In this research, bistriazinone heterocycle was synthesized via a cyclization reaction of bisamidine, thoroughly characterized using elemental analysis, Fourier-transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, and ultraviolet-visible spectroscopy, and subsequently applied to modify a glassy carbon electrode. This modified electrode was tested for Hg2+ detection, leveraging the strong coordination between amino groups or nitrogen centers and Hg2+. Under optimal conditions using square wave voltammetry, the developed analytical method achieved a detection limit of 0.223 ppb, well below the WHO's permissible limit of 6 ppb for mercury species in drinking water. The senor demonstrated excellent selectivity for Hg2+, even in the presence of potentially interfering ions. Furthermore, it exhibited good reproducibility (RSD, 3.16%) and notable cycle stability (RSD, 7.14%). Validation in tap water samples yielded a promising recovery rate of 94% for Hg2+ detection, highlighting the practical applicability of the developed sensor. Additionally, density functional theory (DFT)-based calculations were conducted to elucidate the mechanisms underlying Hg2+ detection.

In this study, we present a novel approach to enhancing the degradation of acetaminophen (ACT) using nanostructured hybrid nanofibers. The hybrid nanofibers were produced by employing both sol-gel and electrospinning methodologies, integrating precise quantities of silver (Ag) and boron nitride (BN) nanosheets into titanium oxide (TiO2) nanofibers and halloysite nanotubes (HNT). We extensively examined the morphology, structure, and optical properties of these materials by employing scanning electron microscopy, X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy in our analysis. In the case of the HNT-TiO2 composite, the introduction of Ag nanoparticles at concentrations of 0.5%, 1.5%, and 3% led to a significant improvement in photocatalytic activity. Under visible light exposure for 4 h, the photocatalytic activity increased from 63% (HNT-TiO2) to 78.92%, 91.21%, and 92.90%, respectively. This enhancement can be attributed to the role of Ag nanoparticles as co-catalysts, facilitating the separation of electrons and holes generated during the photocatalytic process. Furthermore, BN nanosheets served as co-catalysts, capitalizing on their distinct attributes, including exceptional thermal conductivity, chemical stability, and electrical insulation. The incorporation of BN nanosheets into the Ag (3%)/HNT-TiO2 composite at a concentration of 5% resulted in a remarkable increase in ACT degradation efficiency. The degradation efficiency improved from 59.47% to an impressive 99.29% within a 2-h irradiation period due to the presence of BN nanosheets. Toxicity and scavenging assays revealed that OH•−, O2•−, and h+ were the major contributors to ACT degradation. Moreover, across five consecutive cycles, the Ag-BN/HNT-TiO2 composite exhibited consistent and stable performance, underscoring the significant contributions of Ag and BN in augmenting the photocatalytic capabilities of the composite. Overall, our findings suggest that this novel hybrid nanofiber composite holds great promise for practical applications in environmental remediation due to its improved photocatalytic activity and stability.

In this study, we present a novel approach to enhancing the degradation of acetaminophen (ACT) using nanostructured hybrid nanofibers. The hybrid nanofibers were produced by employing both sol-gel and electrospinning methodologies, integrating precise quantities of silver (Ag) and boron nitride (BN) nanosheets into titanium oxide (TiO2) nanofibers and halloysite nanotubes (HNT). We extensively examined the morphology, structure, and optical properties of these materials by employing scanning electron microscopy, X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy in our analysis. In the case of the HNT-TiO2 composite, the introduction of Ag nanoparticles at concentrations of 0.5%, 1.5%, and 3% led to a significant improvement in photocatalytic activity. Under visible light exposure for 4 h, the photocatalytic activity increased from 63% (HNT-TiO2) to 78.92%, 91.21%, and 92.90%, respectively. This enhancement can be attributed to the role of Ag nanoparticles as co-catalysts, facilitating the separation of electrons and holes generated during the photocatalytic process. Furthermore, BN nanosheets served as co-catalysts, capitalizing on their distinct attributes, including exceptional thermal conductivity, chemical stability, and electrical insulation. The incorporation of BN nanosheets into the Ag (3%)/HNT-TiO2 composite at a concentration of 5% resulted in a remarkable increase in ACT degradation efficiency. The degradation efficiency improved from 59.47% to an impressive 99.29% within a 2-h irradiation period due to the presence of BN nanosheets. Toxicity and scavenging assays revealed that OH center dot-, O-2(center dot-), and h(+) were the major contributors to ACT degradation. Moreover, across five consecutive cycles, the Ag-BN/HNT-TiO2 composite exhibited consistent and stable performance, underscoring the significant contributions of Ag and BN in augmenting the photocatalytic capabilities of the composite. Overall, our findings suggest that this novel hybrid nanofiber composite holds great promise for practical applications in environmental remediation due to its improved photocatalytic activity and stability.

Immobilization of active Trypsin in Layered Double Hydroxides (LDH) has been successfully obtained by soft chemistry processes through coprecipitation and anion exchange reaction. Thin films of bioactive LDH-Trypsin membranes were coated on gold electrode for measurements of biosensing response toward a model substrate, N-Benzoyl-L-Arginine Ethyl Ester (BAEE). The adhesion and conductivity performance of the films were significantly enhanced by a chemical treatment of gold surface and Zn2Al LDH by mercaptoethane sulfonate anion (MS). LDH-Trypsin based biosensors were studied by Electrochemical Impedance Spectroscopy and charge transfer mechanisms were investigated using Nyquist diagram simulation using electrical equivalent circuits. Nanostructuration of Zn2Al-MS and Zn2Al-MS-Trypsin at the surface of gold and MS modified gold electrodes have a strong influence on the protonic conductivity of the biosensor.

The Ain El Bey abandoned mine, in North-West Tunisia, fits into the geodynamic context of the European and African plate boundary. Ore deposit corresponds to veins and breccia of multiphase Cu–Fe-rich mineralization related to various hydrothermal fluid circulations. Petro-mineralogical studies indicate a rich mineral paragenesis with a minimum of seven mineralization phases and, at least, six pyrite generations. As is also the case for galena and native silver, native gold is observed for the first time as inclusion in quartz which opens up, thus, new perspectives for prospecting and evaluating the potential for noble metals associated with the mineralization. Scanning Electron Microscope—Energy Dispersive Spectroscopy and Transmission electron microscopy analyses show, in addition, a large incorporation of trace elements, including Ag and Au, in mineral structures such as fahlores (tetrahedrite-tennantite) and chalcopyrite ones. The mineral/mineral associations, used as geothermometers, gave estimated temperatures for the mineralizing fluids varying from 254 to 330 °C for phase III, from 254 to 350 °C for phase IV, and from 200 to 300 °C for phases V and VI. The seventh and last identified mineralization phase, marked by a deposit of native gold, reflects a drop in the mineralizing fluid’s temperature (< 200 °C) compatible with boiling conditions. Such results open up perspectives for the development of precious metal research and the revaluation of the Cu–Fe ore deposit at the Ain El Bey abandoned mine, as well as at the surrounding areas fitting in the geodynamic framework of the Africa-Europe plate boundary.

Halloysite nanotubes (HNTs) are clay minerals with a tubular structure that can be used for many different applications in place of carbon nanotubes. Indeed, HNTs display low/non-toxicity, are biocompatible, and can be easily prepared. Moreover, the aluminum and silica groups present on HNTs’ inner and outer surfaces facilitate the interaction with various functional agents, such as alkalis, organosilanes, polymers, surfactants, and nanomaterials. This allows the deposition of different materials, for instance, metal and non-metal oxides, on different substrate types. This review article first briefly presents HNTs’ general structure and the various applications described in the last 20 years (e.g., drug delivery, medical implants, and energy storage). Then, it discusses in detail HNT applications for water purification (inorganic and organic pollutants). It focuses particularly on HNT-TiO2 composites that are considered very promising photocatalysts due to their high specific surface area and adsorption capacity, large pore volume, good stability, and mechanical features.

Copper-rich deposits associated with magmatism at the Oued Belif -Ain El Araar area in North-western Tunisia fit into the geodynamic framework of the Tell-Rif orogenic belt of North Africa that extends westward to the Betic Cordilleras in Spain at the african and european plate boundary. The deposits have been considerably studied. However, the prevailing conditions of pressure, volume, temperature and composition (P-V-T-X) of the mineralizing fluids are still elusive. In this study, three types of fluid inclusions were distinguished for the mineralized facies: primary polyphase brine inclusions (Type I: liquid + vapor + halite + sylvite), primary sylvite (Type II-a: liquid + vapor + sylvite) and halite (Type II-b: liquid + vapor + halite) bearing inclusions and biphasic secondary vapor-rich and liquid-rich inclusions (Type III: liquid + vapor). Raman spectroscopy show that Type I and II a-b inclusions are in the CO 2 –H 2 O–NaCl–KCl, CO 2 –H 2 O–NaCl and CO 2 –H 2 O–KCl systems, whereas Type III pertains to the CO 2 –H 2 O system. Estimations of Pressure-Temperature fluid trapping conditions, for all mentioned inclusions, demonstrate a physicochemical fluid evolution from the highest temperature brine inclusions ( T t = 500°C; P t = 980 bars), related to the porphyry phase, to the low temperature biphasic inclusions ( T t = 131°C; P t = 221 bars) related the latest epithermal phase .The coexistence of liquid-rich and vapor-rich inclusions homogenizing at lower temperatures, confirms the establishment of boiling conditions responsible of Au–(Ag) enrichment in the last mineralizing phases. Comparable temperature conditions in similar magmatic related deposits are also mentioned in southern Spain (Rodalquilar gold mine, e.g., Arribas et al., 1995) where the mineralizing fluid temperatures mentioned vary from 175°C for epithermal deposits to more than 400°C for porphyry ones. The geochemical behavior of trace element indicates positive anomalies in mobile elements (hygromagmaphiles), those linked to Au, granitophiles (mainly W and Mo) and chalcophiles indicating a supply of metals of deep origin and mineralizing fluids with marked magmatic differentiation.

In this study, we combined electrospinning of a large amount of halloysite (HNT, 95%) with nitriding to produce N-HNT-TiO2 composite nanofibers (N-H95T5 hereafter) to be used for acetaminophen (ACT) photodegradation. Investigation of the morphological and structural properties of the obtained materials did not highlight any significant difference in their morphological features and confirmed that nitrogen was evenly distributed in the samples. Photocatalytic tests under visible light showed that acetaminophen photodegraded faster in the presence of samples with nitrogen (N-H95T5) than without (H95T5 nanofibers). Moreover, the N-H95T5 nanocomposite photocatalytic activity did not change after repeated utilization (five cycles). The addition of scavengers during photocatalytic tests showed the key implication of OH•−, O2•− and h+ radicals in acetaminophen degradation. These results indicated that N–H95T5 composite nanofibers could be considered a cheap multifunctional material for photodegradation and could open new prospects for preparing tunable photocatalysts.

The structure, porosity, and functionality of synthesized chitosan-clay nanocomposites (NCs) are examined throughout this work in relation to the initial stoichiometry and octahedral cavity occupation of the clay fraction. Dioctahedral and trioctahedral smectite are selected as starting materials. X-Ray Diffraction analysis (XRD) confirms the accomplishment of the NCs synthesis process. The stoichiometry fluctuation implies a crystallite exfoliation process provided that the clay fraction contribution must not reach twice the organic ones. From 1:3 stoichiometry ratio, The intercalation process is enhanced by the interlamellar space (IS) closures, and crystallite size increases with crystallinity degree. According to transmission electron microscopy-energy dispersive X-ray (TEM-EDX) investigations, the exfoliation of "clay-particles" wrapping the organic fraction and the intercalation process occurred as the clay fraction abundance increased. Despite the low proportion approved from the synthesis beginning process, Fourier transform infrared spectroscopy (FTIR) reveals the polymer fraction characteristics absorption bands. The Brunauer, Emmett and Teller (BET) analysis of specific surface area and Barrett-Joyner-Halenda (BJH) Analysis of pore size distribution (PSD) supports the findings from TEM/EDX. For slightly saturated soil solution with Pb2+ or Cd2+ cation, Atomic absorption spectroscopy (AAS) evaluate the NCs adsorption capacity. The outcomes are extremely positive for dioctahedral smectite.

The intrinsic cation exchange capacity (CEC) of clays is a crucial characteristic that offers a tool to assess their overall chemical properties. For the confinement of industrial and radioactive waste, clays are deployed as geological barriers, hence it is important to consider how they will react under external stresses. With respect to the electronegativity rate and cation ionic potential, the impact of a series of sequential cation exchange processes with heavy metals exchangeable cations was the main emphasis of this work. Using X-ray diffraction (XRD) profile modeling to assess interlayer space (IS) deformation and highlight geochemical alteration, the structural reactivity of Na-rich montmorillonite was investigated. To determine the ideal structural characteristics defining IS configuration, the study contrasted estimated reflections produced from theoretical models with those produced experimentally from 00l reflections. Per each exchanged cation, the results showed a partial CEC saturation and a heterogeneous mixed layer structure (MLS), with heterogeneous hydration behavior continuing to exist regardless the type of exchangeable cation. The established chemical constraint had no effect on the cation hydration sphere for Co (II), Ni (II), Mg (II), Cu (II), and Zn (II) exchangeable cations. However, significant interlamellar water molecule development was observed for the Cd (II), Pb (II), and Ba (II) cations, indicating a major alteration in the discretization of the hydration states and particular hydration heterogeneities. The Cd (II), Pb (II), and Ba cations were most affected by these alterations, which resulted in a constrained and inhibited CEC performance. The theoretical decomposition of the observed XRD profiles was used to show the existence of multiple layer type populations and their stacking mode, with most of the studied samples showing a tendency toward segregated stacking configuration. Moreover, as a function of the applied stress, the CEC of the stress samples gradually dropped.

The photocatalytic degradation process and absorption kinetics of the aqueous solution of the Cibacron Brilliant Yellow 3G-P dye (Y) were investigated under UV-Vis light. Pure barium titanate BaTiO3 (BT) and cobalt ion-substituted barium Ba1−xCoxTiO3 (x = 0, …, 1) nano-compound powders (BCT) were synthesized using the sol–gel method and colloidal solution destabilization, and utilized as photocatalysts. The powder X-ray diffraction (PXRD) crystal structure analysis of the BT nanoparticles (NPs) revealed a prominent reflection corresponding to the perovskite structure. However, impurities and secondary phase distributions were qualitatively identified in the PXRD patterns for x ≥ 0.2 of cobalt substitution rate. Rietveld refinements of the PXRD data showed that the BCT nano-compound series undergoes a transition from perovskite structure to isomorphous ilmenite-type rhombohedral CoTiO3 (CT) ceramic. The nanoparticles produced displayed robust chemical interactions, according to a Fourier transform infrared spectroscopy (FTIR) analysis. The BT and BCT nanoparticles had secondary hexagonal phases that matched the PXRD results and small aggregated, more spherically shaped particles with sizes ranging from 30 to 114 nm, according to transmission electron microscopy (TEM). Following a thorough evaluation of BCT nano-compounds with (x = 0.6), energy-dispersive X-ray (EDX) compositional elemental analysis revealed random distributions of cobalt ions. Through optical analysis of the photoluminescence spectra (PL), the electronic structure, charge carriers, defects, and energy transfer mechanisms of the compounds were examined. Due to the cobalt ions being present in the BT lattice, the UV-visible absorption spectra of BCT showed a little red-shift in the absorption curves when compared to pure BT samples. The electrical and optical characteristics of materials, such as their photon absorption coefficient, can be gathered from their UV-visible spectra. The photocatalytic reaction is brought about by the electron–hole pairs produced by this absorption. The estimated band gap energies of the examined compounds, which are in the range of 3.79 to 2.89 eV, are intriguing and require more investigation into their potential as UV photocatalysts. These nano-ceramics might be able to handle issues with pollution and impurities, such as the breakdown of organic contaminants and the production of hydrogen from water.