Enhancing Li+ recovery in brine mining: integrating next-gen emotional AI and explainable ML to predict adsorption energy in crown ether-based hierarchical nanomaterials.

Artificial intelligence (AI) is being employed in brine mining to enhance the extraction of lithium, vital for the manufacturing of lithium-ion batteries, through improved recovery efficiencies and the reduction of energy consumption. An innovative approach was proposed combining Emotional Neural Networks (ENN) and Random Forest (RF) algorithms to elucidate the adsorption energy (AE) (kcal mol-1) of Li+ ions by utilizing crown ether (CE)-incorporated honeycomb 2D nanomaterials. The screening and feature engineering analysis of honeycomb-patterned 2D materials and individual CE were conducted through Density Functional Theory (DFT) and Gaussian 16 simulations. The selected honeycomb-patterned 2D materials encompass graphene, silicene, and hexagonal boron nitride, while the specific CEs evaluated are 15-crown-5 and 18-crown-6. The crown-passivated 2D surfaces held a significant adsorption site through van der Waals forces for efficient recovery of Li+ ions. ENN predicted the targeted adsorption sites with high precision and minimal deviation. The eTAI (XAI) based Shapley Additive exPlanations (SHAP) was also explored for insight into the feature importance of CE embedded 2D nanomaterials for the recovery of Li+ ions. The extreme gradient boosting algorithm (XGBoost) model demonstrated a RT-2-MAPE = 0.4618% and ENN-2-MAPE = 0.4839% for the feature engineering analysis. This research would be an insight into the AI-driven nanotechnology that presents a viable and sustainable approach for the extraction of natural resources through the application of brine mining.

Facile engineering of mesoporous silica for the effective removal of anionic dyes from wastewater: Insights from DFT and experimental studies.

The discharge of dye effluents from the textile industries has become a major environmental issue due to its potential to impart serious harm to human health and aquatic life. Mesoporous silica due to its high chemical stability, large surface area, tunable morphologies, large pore volume and pore size and cost-effectiveness is commonly used to remove such dyes before recycling of the wastewater for agricultural, domestic, and industrial applications. However, the low colloidal stability, the fast aggregation of the silica particles and the slow etching of the silica surface often results in the fast deactivation of the adsorbents and limits their long-term applications. In this study, we report the functionalization of mesoporous silica (SBA-15) with ZnO nanoparticles for the effective removal of anionic dyes. The Zn-silica exhibited highly positive surface with a dipole moment of 172 Debye and high charge transfer efficacy with an energy bandgap (ΔE) of 3.35 eV as revealed by quantum chemical DFT simulations. It achieved excellent removal of Alizarin red dye reaching a removal efficiency of 99.99 % and an adsorption capacity of 50 mg/g. In the presence of heavy metal ions commonly present in wastewater (Cd2+, Co2+, Zn2+, Ni2+, Cu2+ and Hg2+), the Zn-silica maintain excellent stability, high selectivity, and reusability within 5 cycles without a significant decline in efficiency. This study thus presents an effective way of wastewater purification on cost-effective adsorbents for meeting the water scarcity demands.

Integrated clustering analysis for delineating seawater intrusion and heavy metals in Arabian Gulf Coastal groundwater of Saudi Arabia.

The intrusion of seawater (SWI) into coastal aquifers is a major concern worldwide, affecting the quantity and quality of groundwater resources. The region of Saudi Arabia that lies along the eastern coast has been affected by SWI, making it crucial to accurately identify and monitor the affected areas. This investigation aimed to map the degree of seawater intrusion in a complex aquifer system in the study area using an integrated clustering analysis approach. The study collected 41 groundwater samples from wells penetrating multi-layered aquifers, and the samples were analyzed for physicochemical properties and major ions. Clustering analysis methods, including Hierarchical Clustering Analysis (double-clustering) (HCA-DC), K-mean (KMC), and fuzzy k-mean clustering (FKM), were employed to evaluate the spatial distribution and association of the groundwater properties. The results revealed that the analyzed GW samples were divided into four clusters with varying degrees of SWI. Clusters A, B, C, and D contained GW samples with very low (fsea of 1.9%), high (fsea of 14.9%), intermediate (fsea of 7.9%), and low (fsea of 5.2%) degrees of SWI, respectively. FKM clustering exhibited superior performance with a silhouette score of 0.83. Additionally, the study found a direct correlation between the degree of SWI and increased concentrations of boron, strontium, and iron, demonstrating SWI's impact on heavy metal levels. Notably, the boron concentration in cluster B, which endured high SWI, exceeded WHO guidelines. The study demonstrates the value of clustering analysis for accurately monitoring SWI and associated heavy metals. The findings can guide policies to mitigate SWI impacts and benefit groundwater-dependent communities. Further research can help develop effective strategies to mitigate SWI effects on groundwater quality and availability.

Highly Permeable Sulfonated Polydopamine Integrated MXene Membranes for Efficient Surfactant-Stabilized Oil-in-Water Separation.

MXene is an incredibly promising two-dimensional material with immense potential to serve as a high-performing separating or barrier layer to develop advanced membranes. Despite the significant progress made in MXene membranes, two major challenges still exist: (i) effectively stacking MXene nanosheets into defect-free membranes and (ii) the high fouling tendency of MXene-based membranes. To address these issues, we employed sulfonated polydopamine (SPD), which simultaneously serves as a binding agent to promote the compact assembling of Ti3C2Tx MXenes (MX) nanosheets and improves the antifouling properties of the resulting sulfonated polydopamine-functionalized MX (SPDMX) membranes. The SPDMX membrane was tested for challenging surfactant-stabilized oil-in-water separation with an impressive efficiency of 98%. Moreover, an ultrahigh permeability of 1620 LMH/bar was also achieved. The sulfonation of PD helps in improving the antifouling characteristics of SPDMX by developing a strong hydration layer and enhancing the oleophobicity of the membrane. The underwater SPDMX membrane appeared superoleophobic with an oil contact angle of 153°, whereas the ceramic membrane exhibited an oil contact angle of 137°. The SPDMX membranes showed an improved flux recovery (31%) compared to the nonsulfonated counterpart. This work highlights the appropriate functionalization of MXene as a promising approach to developing MXene membranes with high permeation flux and better antifouling characteristics for oily wastewater treatment.

Fabrication of a New Rationally Designed Mussel-Inspired Cationic Amphiphilic Terpolymer to Enhance the Separation and Anti-Fouling Performance of Membranes.

Polyvinylidene fluoride (PVDF) membrane-based systems for treating oily wastewater are prone to fouling. Herein, we introduced a novel mussel-inspired cationic amphiphilic terpolymer consisting of monomers N,N-diallyldimethylammonium chloride (DADMAC), N,N-diallyltetradecan-1-ammonium chloride (DTDAC), and mussel-inspired N,N-diallyldopamine hydrochloride (DADAHC) to improve the performance and characteristics of the PVDF membranes for oil-in-water emulsion separations. The cationic terpolymer, poly(DADMAC-co-DTDAC-co-DADAHC), shortened as PDDD, was synthesized in excellent yields via free radical polymerization and has good compatibility with the PVDF owing to the presence of hydrophobic long alkyl chains in DTDAC. The presence of dopamine motifs helps stabilize the PDDD-PVDF membrane by chelating with Fe3+ ions. The water contact angle on the PDDD-incorporated PVDF membranes was reduced from 87.6 to 54.6°, demonstrating improved hydrophilicity than pristine PVDF (M-0). The incorporation of PDDD into the PVDF improved the separation efficiencies of the membrane, which reached up to 99% while treating the oil-in-water emulsions. Incorporating PDDD into PVDF has significantly enhanced the anti-fouling characteristics of the membranes, which are indicated by their remarkable flux recovery ratio (FRR) (up to 92%). The hydrophobic and hydrophilic groups worked synergetically to enhance the performance of the fabricated membrane.

Hemin-Modified Multi-Walled Carbon Nanotube-Incorporated PVDF Membranes: Computational and Experimental Studies on Oil-Water Emulsion Separations.

The separation of oil/water emulsions has attracted considerable attention for decades due to the negative environmental impacts brought by wastewater. Among the various membranes investigated for separation, polyvinylidene fluoride (PVDF) membranes have shown significant advantages of ease of fabrication, high selectivity, and fair pore distribution. However, PVDF membranes are hydrophobic and suffer from severe fouling resulting in substantial flux decline. Meanwhile, the incorporation of wettable substrates during fabrication has significantly impacted the membrane performance by lowering the fouling propensity. Herein, we report the fabrication of an iron-containing porphyrin (hemin)-modified multi-walled carbon nanotube incorporated PVDF membrane (HA-MWCNT) to enhance fouling resistance and the effective separation of oil-in-water emulsions. The fabricated membrane was thoroughly investigated using the FTIR, SEM, EDX, AFM, and contact angle (CA) analysis. The HA-MWCNT membrane exhibited a water CA of 62° ± 0.5 and excellent pure water permeance of 300.5 L/m2h at 3.0 bar (400% increment), in contrast to the pristine PVDF, which recorded a CA of 82° ± 0.8 and water permeance of 59.9 L/m2h. The hydrophilic HA-MWCNT membrane further showed an excellent oil rejection of >99% in the transmembrane pressure range of 0.5−2.5 bar and a superb flux recovery ratio (FRR) of 82%. Meanwhile, the classical molecular dynamics (MD) simulations revealed that the HA-MWCNT membrane had greater solvent-accessible pores, which enhanced water permeance while blocking the hydrocarbons. The incorporation of the hemin-modified MWCNT is thus an excellent strategy and could be adopted in the design of advanced membranes for oil/water separation.

Designing of nanotextured inorganic-organic hybrid PVDF membrane for efficient separation of the oil-in-water emulsions.

The separation of the emulsified oil/water is one of the critical environmental challenges. The PVDF membranes have been found helpful for separation, but rapid fouling makes them less attractive in treating oil-in-water emulsions. The design of antifouling membranes has become an area of deep interest. Herein, developing a novel modified PVDF ultrafiltration membrane was reported by doping the pyrrole and solidifying it in a ferric-containing coagulation bath, resulting in a unique nanotextured PVDF membrane (CCB-Fe/PPnp-PVDF) to separate the oil/water emulsions. The resultant CCB-Fe/PPnp-PVDF membrane was thoroughly characterized using the FTIR, FE-SEM, EDX, mapping, AFM, and contact analyzer. The hydrophilicity of the CCB-Fe/PPnp-PVDF was substantially improved, and the water contact angle was reduced from 81Ö¯ ± 0.9Ö¯ to 44Ö¯ ± 1.7Ö¯. The CCB-Fe/PPnp-PVDF membrane flux increased by 121% compared to the pristine PVDF membrane, with high separation efficiency of 99%. The hydrophilic nanotextured surface of the CCB-Fe/PPnp-PVDF membrane showed good antifouling behavior, with a flux recovery ratio (FRR) of more than 96%. Irreversible flux was just less than 4%. The high flux recovery ratio indicated that the nanotextured surface produced by the Fe/PPnp had prevented the blockage of the membrane pores and compact cake layer formation, which makes it an excellent membrane for oil/water emulsion separation. This strategy can be adopted for designing advanced membranes for separation applications.

The Photovoltaic Cell Based on CIGS: Principles and Technologies.

Semiconductors used in the manufacture of solar cells are the subject of extensive research. Currently, silicon is the most commonly used material for photovoltaic cells, representing more than 80% of the global production. However, due to its very energy-intensive and costly production method, other materials appear to be preferable over silicon, including the chalcopyrite-structured semiconductors of the CIS-based family (Cu(In, Ga, Al) (Se, S)2). Indeed, these compounds have bandwidths between 1 eV (CuInSe2) and 3 eV (CuAlS2), allowing them to absorb most solar radiation. Moreover, these materials are currently the ones that make it possible to achieve the highest photovoltaic conversion efficiencies from thin-film devices, particularly Cu(In, Ga)Se2, which is considered the most efficient among all drifts based on CIS. In this review, we focus on the CIGS-based solar cells by exploring the different layers and showing the recent progress and challenges.

Recent Progress in Microfiltration/Ultrafiltration Membranes for Separation of Oil and Water Emulsions.

Oily wastewater has become one of the leading causes of environmental pollution. A massive quantity of oily wastewater is released from industries, oil spills, and routine activities, endangering the ecosystem's sustainability. Due to the enormous negative impact, researchers put strenuous efforts into developing a sustainable solution to treat oily wastewater. Microfiltration/ultrafiltration membranes are considered an efficient solution to treat oily wastewater due to their low cost, small footprint, facile operation, and high separation efficiencies. However, membranes severely fouled during the separation process due to oil's adsorption and cake layer formation, which shortens the membranes' life. This review has critically discussed the microfiltration/ultrafiltration membrane synthesizing methods and their emulsion's separation performance. In the end, key challenges and their possible solutions are highlighted to provide future direction to synthesize next-generation membranes.

The Role of Sulphonic and Phosphoric Pendant Groups on the Diffusion of Monovalent Ions in Polyelectrolyte Membranes: A Molecular Dynamics Study.

Lithium-ion consumption has risen significantly in recent years due to its use in portable devices. Alternative sources of lithium, which include the recovery from brine using the sustainable and eco-friendly electrodialysis technology, has been explored. This technology, however, requires effective cation-exchange membranes that allow the selective permeation of lithium ions. In this study, we have investigated, via molecular dynamics simulations, the role of the two common charged groups, the sulfonic and the phosphoric groups, in promoting the adsorption of monovalent ions from brine comprising Li+, Na+, Mg2+, and Ca2+ ions. The analysis of the mean square displacement of the ions revealed that Li+ and Na+ ions exhibit superior diffusion behaviors within the polyelectrolyte system. The O-atoms of the charged groups bind strongly with the divalent ions (Mg2+ and Ca2+), which raises their diffusion energy barrier and consequently lowers their rate of permeation. In contrast, the monovalent ions exhibit weaker interactions, with Na+ being slightly above Li+, enabling the permeation of Li+ ions. The present study demonstrates the role of both charged groups in cation-exchange membranes in promoting the diffusion of Li+ and Na+ ions, and could serve as a guide for the design of effective membranes for the recovery of these ions from brine.

Thermal energy storage and thermal conductivity properties of fatty acid/fatty acid-grafted-CNTs and fatty acid/CNTs as novel composite phase change materials.

In recent year, fatty acids (FAs) are heavily studied for heat storage applications and they have shown promising advantages over other organic phase change materials (PCMs). Among the FAs; capric, palmitic and stearic acids are the most studied PCMs. Several researchers have investigated these FAs and tried to improve their thermal properties, mainly by adding different high conducting fillers, such as graphite, metal foams, CNTs, graphene etc. In most cases, these fillers improved the thermal conductivity and heat transfer property but reduce the heat storage capacity considerably. These composites also lose the mixing uniformity during the charging and discharging process. To overcome these issues, selected FAs were grafted on the functionalized CNT surfaces and used as conductive fillers to prepare FA based composite PCMs. This process significantly contributed to prevent the drastic reduction of the overall heat storage capacity and also showed better dispersion in both solid and liquid state. Thermal cycling test showed the variations in the thermal energy storage values of all composite PCMs, however, within the tolerable grade and they had appreciable phase change stability and good chemical stability even after 2,000 cycles.

3D silicon shapes through bulk nano structuration by focused ion beam implantation and wet etching.

The work presented in this paper concerns the synthesis of silicon (Si) 2D and 3D nanostructures using the delayed effect, caused by implanted Ga ions, on the dissolution of Si in aqueous solutions of tetramethylammonium hydroxide (TMAH). The crystalline silicon substrates (100) are first cleaned and then hydrogenated by immersion in an aqueous solution of hydrofluoric acid. The ion implantation is then carried out by a focused ion beam by varying the dose and the exposure time. Chemical etching in aqueous solutions of TMAH at 80 °C leads to the selective dissolution of the Si planes not exposed to the ions. The preliminary results obtained in the laboratory made it possible to optimize the experimental conditions for the synthesis of 2D and 3D nanoobjects of controlled shape and size. Analysis by transmission electron microscopy and energy dispersive x-ray showed the amorphous nature of the nanostructures obtained and the presence of 5%-20% Ga in these nanoobjects. The first experiments of recrystallization by rapid thermal annealing allowed to reconstitute the crystal structure of these nanoobjects.

Surface Characteristics of Silicon Nanowires/Nanowalls Subjected to Octadecyltrichlorosilane Deposition and n-octadecane Coating.

In this study, nanowires/nanowalls were generated on a silicon wafer through a chemical etching method. Octadecyltrichlorosilane (OTS) was deposited onto the nanowire/nanowall surfaces to alter their hydrophobicity. The hydrophobic characteristics of the surfaces were further modified via a 1.5-µm-thick layer of n-octadecane coating on the OTS-deposited surface. The hydrophobic characteristics of the resulting surfaces were assessed using the sessile water droplet method. Scratch and ultraviolet (UV)-visible reflectivity tests were conducted to measure the friction coefficient and reflectivity of the surfaces. The nanowires formed were normal to the surface and uniformly extended 10.5 µm to the wafer surface. The OTS coating enhanced the hydrophobic state of the surface, and the water contact angle increased from 27° to 165°. The n-octadecane coating formed on the OTS-deposited nanowires/nanowalls altered the hydrophobic state of the surface. This study provides the first demonstration that the surface wetting characteristics change from hydrophobic to hydrophilic after melting of the n-octadecane coating. In addition, this change is reversible; i.e., the hydrophilic surface becomes hydrophobic after the n-octadecane coating solidifies at the surface, and the process again occurs in the opposite direction after the n-octadecane coating melts.

The collagen assisted self-assembly of silicon nanowires.

The paper reports on self-assembly of silicon nanowire junctions assisted by protocollagen, a low cost soluble long fiber protein and precursor of collagen fibrils. First, the collagen was combed on an octadecyl-terminated silicon surface with gold electrodes. Then the combed surface was exposed to an aqueous suspension of silicon nanowires. In order to increase electrostatic interactions between the positively charged collagen and the nanowires, the nanowires were chemically modified with negatively charged sulfonate groups. The interaction of collagen with the sulfonated nanowires, which mimics the native collagen/heparin sulfate interaction, induced self-assembly of the nanowires localized between gold electrodes. The proof of concept for the formation of spontaneous electrode-nanowire-electrode junctions using collagen as a template was supported by current-voltage measurements.