Aqueous Systems Research Articles

Synthesis and separation of silver nanoparticles using an Aqueous Two-Phase System with citrate as reducing agent

Synthesis and separation of silver nanoparticles using an Aqueous Two-Phase System with citrate as reducing agent

Preparation of Nanoparticle Doped Metal-organic Framework (MOF) and its Potential Use for Photodegradation of Antibiotics in Water: A Review

Abstract: Semiconductors have gained recognition as efficient photocatalysts for the degradation of antibiotics in water. However, their performance is limited due to poor absorption of light, recombination of electron-hole pairs, and poor recovery from an aqueous solution. This study reviewed the inclusion of semiconductor nanoparticles in a metal-organic framework (MOF), forming nanoparticle@ MOF composite to overcome these challenges. Three methods including ship-in-bottle, bottlearound- ship, and one-step synthesis were identified for the synthesis of nanoparticle@MOF composite. Among the synthesis methods, the one-step method remains promising with high prospects. Nanoparticle@ MOF composite has exhibited high efficiency in removing antibiotics in an aqueous system utilizing visible light as a photo source for promoting the process. Despite the success achieved, there is a need for large-scale studies and cost evaluation to understand better the feasibility and economic implications of the nanoparticle@MOF composite technique as an affordable technique for the purification of an antibiotic-contaminated water system.

Simple preparation and greatly improved oral bioavailability: The supersaturated drug delivery system of quercetin based on PVP K30.

Quercetin, as a representative flavonoid, is widely present in daily diet and has been developed as a dietary supplement due to its beneficial physiological activities. However, the application of quercetin is limited due to its poor water solubility and extensive metabolism. So far, the nano-drug delivery systems designed to improve its bioavailability generally have the shortcomings of low drug loading content and difficulty in industrial production. In order to tackle these problems, quercetin supersaturated drug delivery system (QSDDS) was successfully prepared using solvent method, for which PVP K30 was employed as a crystallization and precipitation inhibitor to maintain the supersaturated state of quercetin in aqueous system. The obtained QSDDS, with a relative high drug loading content of 13%, could quickly disperse in water and form colloidal system with the mean particle size of about 200nm, meanwhile induce the generation of supersaturated quercetin solution more than 12h. In vivo pharmacokinetic study proved that QSDDS achieved a high absolute bioavailability of 36.05%, 10 times as that of physical quercetin suspension, which was dose-dependent with higher bioavailability at higher dose. Considering the simple preparation method, QSDDS provided a feasible strategy and a simple way to improve oral absorption of insoluble flavonoids.

Synergistic π-Conjugation Organic Cathode for Ultra-Stable Aqueous Aluminum Batteries.

Rechargeable aqueous aluminum batteries (AABs) are promising energy storage technologies owing to their high safety and ultra-high energy-to-price ratio. However, either the strong electrostatic forces between high-charge-density Al3+ and host lattice, or sluggish large carrier-ion diffusion toward the conventional inorganic cathodes generates inferior cycling stability and low rate-capacity. To overcome these inherent confinements, a series of promising redox-active organic materials (ROMs) are investigated and a π-conjugated structure ROMs with synergistic C═O and C═N groups is optimized as the new cathode in AABs. Benefiting from the joint utilization of multi-redox centers and rich π-π intermolecular interactions, the optimized ROMs with unique ion coordination storage mechanism facilely accommodate complex active ions with mitigated coulombic repulsion and robust lattice structure, which is further validated via theoretical simulations. Thus, the cathode achieves enhanced rate performance (153.9mAhg-1 at 2.0Ag-1 ) and one of the best long-term stabilities (125.7mAhg-1 after 4,000 cycles at 1.0Ag-1 ) in AABs. Via molecular exploitation, this work paves the new direction toward high-performance cathode materials in aqueous multivalent-ion battery systems.

Simultaneous Purification of Human Interferon Alpha-2b and Serum Albumin Using Bioprivileged Fluorinated Ionic Liquid-Based Aqueous Biphasic Systems.

Interferon alpha-2b (IFN-α2b) is an essential cytokine widely used in the treatment of chronic hepatitis C and hairy cell leukemia, and serum albumin is the most abundant plasma protein with numerous physiological functions. Effective single-step aqueous biphasic system (ABS) extraction for the simultaneous purification of IFN-α2b and BSA (serum albumin protein) was developed in this work. Effects of the ionic liquid (IL)-based ABS functionalization, fluorinated ILs (FILs; [C​2C​1Im][C​4F​9SO​3] and [N​1112(OH)][C​4F​9SO​3]) vs. mere fluoro-containing IL ([C​4C​1Im][CF​3SO​3]), in combination with sucrose or [N​1112(OH)][H​2PO​4] (well-known globular protein stabilizers), or high-charge-density salt K​3PO​4 were investigated. The effects of phase pH, phase water content (%wt), phase composition (%wt), and phase volume ratio were investigated. The phase pH was found to have a significant effect on IFN-α2b and BSA partition. Experimental results show that simultaneous single-step purification was achieved with a high yield (extraction efficiency up to 100%) for both proteins and a purification factor of IFN-α2b high in the enriched IFN-α2b phase (up to 23.22) and low in the BSA-enriched phase (down to 0.00). SDS-PAGE analysis confirmed the purity of both recovered proteins. The stability and structure of IFN-α2b and BSA were preserved or even improved (FIL-rich phase) during the purification step, as evaluated by CD spectroscopy and DSC. Binding studies of IFN-α2b and BSA with the ABS phase-forming components were assessed by MST, showing the strong interaction between FILs aggregates and both proteins. In view of their biocompatibility, customizable properties, and selectivity, FIL-based ABSs are suggested as an improved purification step that could facilitate the development of biologics.

Functionalized 2-Hydrazinobenzothiazole with Bithiophene as a Colorimetric Sensor for Lethal Cyanide Ions and Its Application in Food Samples.

A newly synthesized Schiff's base 2-(2-([2,2'-bithiophen]-5-ylmethylene)hydrazinyl)benzothiazole (BT) was obtained from the condensation reaction between 2-hydrazinobenzothiazole and 2,2-bithiophene-5-carboxaldehyde. The prepared probe BT was subjected to a confirmation of the structural arrangement through NMR, FTIR, ESI-HRMS, and single-crystal XRD spectral analysis. The BT colorimetric sensor showed selectivity and sensitivity toward the cyanide (CN-) ion over other common anions such as ClO4-, Cl-, Br-, F-, I-, NO2-, OH-, HSO4-, and H2PO4- in a partial aqueous system CH3CN/H2O (8:2, v/v). The probe BT detects CN- with the lowest detection range as low as 1.33 × 10-8 M (3.59 ppm); in comparison to that given by WHO guidelines, it is significantly lower. The stoichiometric interaction between the probe BT and analyte CN- was found to be 1:1 (BT/CN-) binding mode using Jobs plot, and further association binding affinity was calculated to be 6.64 × 10-3 M-1. Additionally, these results were further supported by the FTIR and DFT calculations, as well as the 1H NMR titration analysis, which complemented the binding data. The sensor probe BT was successfully employed in a cotton swab test kit approach and also in smartphone-assisted applications for the determination of CN- ions. Finally, the outstanding sensing properties of probe BT aided the quantitative detection of CN- ions, and it could be further applied to a variety of food samples, including apple seeds, sprouting potatoes, and cassava.

Nanosecond solvation dynamics in a polymer electrolyte for lithium batteries.

Solvation dynamics critically affect charge transport. Spectroscopic experiments and computer simulations show that these dynamics in aqueous systems occur on a picosecond timescale. In the case of organic electrolytes, however, conflicting values ranging from 1 to several 100 picoseconds have been reported. We resolve this conflict by studying mixtures of an organic polymer and a lithium salt. Lithium ions coordinate with multiple polymer chains, resulting in temporary crosslinks. Relaxation of these crosslinks, detected by quasielastic neutron scattering, are directly related to solvation dynamics. Simulations reveal a broad spectrum of relaxation times. The average timescale for solvation dynamics in both experiment and simulation is one nanosecond. We present the direct measurement of ultraslow dynamics of solvation shell break-up in an electrolyte.

Application of Aqueous Two-Phase Systems with Thermoseparating Polymers (EOPO) as a Method for Extractive Fermentation with Neochloris oleoabundans

Extractive fermentation is an in situ method for the production and recovery of biomolecules of interest. Aqueous two-phase systems (ATPS) allow the product to be recovered in one phase of the system, reducing unit operations in the bioprocess. Thermosensitive polymers such as EOPOs are an interesting alternative to be applied in ATPS. In this work, different EOPOs were tested in an extractive fermentation strategy with the green microalgae Neochloris oleoabundans to provide a basis for future implementations of these systems in microalgae bioprocesses. Extractive fermentations were carried out with two EOPOs of different molecular weights (3900 and 12,000 g/mol) at concentrations of 10% and 15% (w/v). The microalga was incubated axenically under two different sets of conditions for 21 and 45 days, respectively. Cell counts were performed, and cell growth curves were obtained. Additionally, a semi-continuous and batch extractive fermentation assay was performed. The extractive fermentation with EOPO showed lower cell growth and a longer adaptation time of the microalgae in the fermentation, and EPS production yields of up to 8–23 g/L were obtained. Extractive fermentation is an interesting method to be implemented in microalgae cultures; however, further conditions need to be explored to achieve an appropriate bioprocess.

Bioactive flavonoids partitioning in a deep eutectic solvent/surfactant aqueous biphasic system: Efficiency and thermodynamics

The present study reports the partitioning behavior of three antioxidant flavonoids, including quercetin, chrysin, and daidzein, in an aqueous biphasic system (ABS) formed using a deep eutectic solvent (DES), a non-ionic surfactant (Triton X-100), and water. The efficiency of this ABS in partitioning the flavonoids was investigated by calculating the partition coefficients and recovery efficiencies at different temperatures. The experimental results showed that in all ABSs the flavonoids under study tend to transfer effectively into the surfactant-rich bottom phase in the order of chrysin > quercetin > daidzein. From analyzing the effect of temperature on the partitioning of antioxidants, thermodynamic transfer properties consists of molar Gibbs energy ∆Gm,Flav°, molar enthalpy ∆Hm,Flav° and molar entropy ∆Sm,Flav°were calculated. It is inferred from the results that partitioning of the flavonoids is spontaneous and endothermic. So, increasing the partition coefficient and recovery percentage of the flavonoids by increasing temperature can be explained by the endothermic nature of partitioning process. Finally, molecular interactions between the flavonoid molecules and ABS components were estimated by applying group contribution method. Also, it can be concluded that the extent of interactions between chrysin and components of the ABS (especially the surfactant TX-100) is more than flavonoids quercetin and daidzein.

Dendrite-free anodes enabled by MOF-808 and ZIF-8 modified glass microfiber separator for ultralong-life zinc-ion hybrid capacitors

Zinc-ion hybrid capacitors (ZIHCs) have been attracted attention for aqueous electrochemical energy storage systems owing to their high safety, low cost, abundant natural resource of zinc, convenient assembly (in an air atmosphere), robust stability with aqueous electrolytes, and the unique electrochemical characteristics of metallic zinc (Zn) as an anode electrode. Nevertheless, the growth of dendrite is the main challenge of zinc electrode in an aqueous electrolyte, leading to short circuit failure. Herein, metal-organic frameworks (MOFs) have been employed to decorate the separator. The porous nature of MOFs has been identified as beneficial for directing uniform zinc deposition. This study focuses on the operational efficiency and lifecycle of ZIHCs utilizing MOFs, specifically MOF-808 and ZIF-8, to modify glass microfiber separators. The results demonstrated that the symmetrical cell using MOF modified separators exhibited high performance, maintaining stable voltage over 1000 h. attributed to the enhanced uniformity of Zn ion flux during striping/plating processes. Additionally, at the current density of 1.0 A g−1, ZICs with MOFs modified separators exhibited higher specific capacities compared to those using the pristine separator and prolonged the cycle life over 20,000 cycles with capacity retention of 56.73 and 63.89 %, respectively. Because the MOFs modified separators can inhibit non-uniform dendritic zinc growth on a zinc anode surface according to the scanning electron micrographs.

Volumetric-acoustic investigations of antihypertensive drug in aqueous acetaminophen system

Captopril is an antihypertensive drug used to lower the blood pressure in living organisms. In order to arbitrate and understand the synergy between antihypertensive drug viz., captopril and antipyretic drug acetaminophen in aqueous system, the density and sound velocity at different temperatures (293.15 to 318.15) K with temperature interval of 5 K were measured using Anton Paar density sound velocity meter (DSA5000M). The experimental measured data were further used to calculate volumetric and acoustic parameters such as apparent and partial molar volume, apparent and partial molar isentropic compressibility, partial molar expansibility, Hepler’s constant, compressibility hydration number, and intermolecular free length. Positive values of apparent molar volume (ϕv) and negative values of apparent and partial molar compressibility (ϕk and ϕko) of captopril in water and aqueous acetaminophen solution has been shown strong intermolecular interactions in solutions. Negative values of Hepler's constant indicate the structure breaking behavior of drug in water.

Evaluation of the effect of water on CO2 absorption in AMP and DMSO systems

Non-aqueous precipitating amine systems for carbon capture allows for CO2 desorption at lower temperatures than conventional aqueous amine systems and can potentially reduce the energy requirement for regeneration. In this work, the influence of water accumulation that may arise from humid gases entering the absorption column was investigated for absorption systems containing 2-amino-2-methyl-1-propanol (AMP) and dimethyl sulfoxide (DMSO). The physical solubility of CO2 decreased with increasing water concentration, as expected from the lower solubility of CO2 in water than in DMSO. The CO2 loading capacity was increased with the addition of water, resulting from formation of bicarbonate with water present in the system. Low lean loadings of 0.1 mol CO2/mol AMP and precipitation was observed in 23 wt% AMP/DMSO with 9 wt% added water, suggesting that some water accumulation might be tolerable while still maintaining the desired properties of the absorption system. NMR was used to study the CO2 reaction products at 30–88 °C. The results suggested that 88 °C can be used for regeneration of the system even with water accumulated in the system. At 80 °C formation of the tentatively assigned species 4,4-dimethyl-1,3-oxazolidin-2-one was observed, indicating that thermal degradation of AMP may occur above this temperature.

Selectivity of PEG/Salt Aqueous Two-Phase System Enhanced by Surfactant@MWCNT Composites.

Aqueous two-phase systems (ATPS) are considered a new type of green separation system, but their low selectivity to target molecules limits their practical application. In this study, we used surfactant@MWCNT as an adjuvant to improve the selectivity of PEG/(NH4)2SO4 ATPS. The surfactants used include Triton X-100 (TX-100), Tween 80, sodium dodecyl sulfate (SDS), sodium dodecyl benzenesulfonate (SDBS), and bis(2-ethylhexyl)sulfosuccinate sodium salt (AOT). Nine aromatic compounds, including syringic acid, vanillin, tryptophan, phenylalanine, tyrosine, mandelic acid, theophylline, theobromine, and cephalexin, were selected as model extracts. The results showed that the use of the surfactant@MWCNT composite as an adjuvant significantly improved the selectivity of the ATPS toward syringic acid among the nine extracts. Moreover, the selectivity of the ATPS for syringic acid with the TX-100/MWCNT composite as the adjuvant is better than that with the Tween 80/MWCNT composite as the adjuvant, followed by that with the anionic surfactant/MWCNT composite as the adjuvant. The enhanced selectivity of ATPS by the surfactant/MWCNT composite is ascribed to the spatial effect and the electrostatic and hydrophobic interactions between the extract and the surfactant adsorbed on the MWCNT.

Highly efficient sorbent utilizing regenerated cellulose as an eco-friendly template for humic acid removal and oil–water separation processes

In this study, a novel and environmentally friendly sorbent was developed utilizing regenerated cellulose (RC) as a renewable resource. The preparation process of the regenerated cellulose hydrogel, following a bottom-up strategy, occurs in an aqueous system and offers the added benefits of temperature-induced gelation and solvent recyclability. The RC/PEI aerogel was prepared through a polyethyleneimine (PEI) modification and di-epoxide crosslinking process, which improves the gel's elastic recovery for the squeezing process and concurrently provides excellent ability to remove humic acid (HA) contaminants. As a result of the HA removal experiment using the RC/PEI aerogel in an aqueous environment, the gel showed an experimental HA adsorption capacity of 124.9 mg/g and qm value of 196.7 mg/g. Furthermore, the prepared RC hydrogel template was successfully transformed into a highly effective oil–water separation sorbent through a hydrophobic alkylated graphene oxide (AGO) coating process. Oil-water separation was carried out using AGO-RC/PEI gel, and it was possible to successfully adsorb the oil and then recover it through the squeezing process. In addition, long-term usability has been validated by demonstrating an oil adsorption capacity of over 84 %, even after ten consecutive reuses.

Degradation of indigo carmine dye with peroxydisulphate ion in aqueous sulphuric acid phase: Kinetic study

AbstractThe quest for cleaner environments is a global concern. Hence, the investigation of degradation of the indigo carmine dye (IC) with peroxydisulphate ion in an aqueous sulphuric acid system with a view to understanding its kinetic degradation and mechanism. The degradation depicts first‐order kinetics in [S2O82−] and [IC], and the degradation mole ratio of IC: S2O82− is 1:1. The degradation rate is dependent on the change in ionic strength and medium permittivity of the system. Also, added ions (NH4+ and NO3−) influence the degradation rate of the dye which further supported the outcome of the change in ionic strength. Free radical participation is ruled out. The experimental rate law is given as (Kk3[H+])[IC][S2O82−]. Owing to the absence of detectable intermediates in the degradation process, an outer‐sphere mechanism is proposed. The study is significant in textile industries and medical settings for making environments less toxic with a well‐understood degradation rate pathway.

Self-assembling and foaming properties of nonionic, cardanol-based surfactants in aqueous solutions

Surfactants from renewable sources have gained attention due to their potential as substituents for petroleum-based chemicals. In this sense, surfactants based on cardanol, a compound abundant in the cashew nutshell liquid, have been proposed as suitable candidates for this purpose. However, their application is hindered by the lack of quantitative and reliable information about their bulk and surface properties in aqueous solutions. In this work, for the first time, three nonionic, cardanol-derived surfactants (7EO, 9EO, and 12EO), with different number of ethylene oxide (EO) units in the polar headgroup, had their foaming performances analyzed and correlated with their respective surface (equilibrium and dynamic surface tension and surface viscoelasticity) and bulk (cloud points, critical micelle concentration, micelle diameter, and viscosity) properties. Depending on the EO number, different scenarios were seen. Solutions containing the 7EO surfactant were below the cloud point at room temperature and presented antifoaming properties. Aqueous solutions of 9EO and 12EO displayed foamability comparable to solutions prepared with a traditionally employed anionic surfactant (sodium dodecyl sulfate, SDS) at the same concentrations. The surfactant 12EO presented a rapid surface adsorption, thus favoring the formation of large amounts of foam during aeration. Furthermore, solutions of 9EO resulted in foams that were considerably more stable than the ones formed by SDS. Such an enhanced stability was attributed to the presence of elongated micelles, formed at the vicinity of the cloud point, that increased solution viscosity and delayed the liquid drainage in the foams. This surfactant also promoted the formation of highly viscoelastic surface films that contributed to foam stabilization. The obtained results suggest that these surfactants can be used in the formulation of new products with a more sustainable character and with improved properties. Moreover, they indicate the important interchange among bulk aggregates, surface properties and foam stability in aqueous surfactant systems.

Stability Increase of Phenolic Acid Decarboxylase by a Combination of Protein and Solvent Engineering Unlocks Applications at Elevated Temperatures.

Enzymatic decarboxylation of biobased hydroxycinnamic acids gives access to phenolic styrenes for adhesive production. Phenolic acid decarboxylases are proficient enzymes that have been applied in aqueous systems, organic solvents, biphasic systems, and deep eutectic solvents, which makes stability a key feature. Stabilization of the enzyme would increase the total turnover number and thus reduce the energy consumption and waste accumulation associated with biocatalyst production. In this study, we used ancestral sequence reconstruction to generate thermostable decarboxylases. Investigation of a set of 16 ancestors resulted in the identification of a variant with an unfolding temperature of 78.1 °C and a half-life time of 45 h at 60 °C. Crystal structures were determined for three selected ancestors. Structural attributes were calculated to fit different regression models for predicting the thermal stability of variants that have not yet been experimentally explored. The models rely on hydrophobic clusters, salt bridges, hydrogen bonds, and surface properties and can identify more stable proteins out of a pool of candidates. Further stabilization was achieved by the application of mixtures of natural deep eutectic solvents and buffers. Our approach is a straightforward option for enhancing the industrial application of the decarboxylation process.

Extraction of 5-Hydroxymethylfurfural and Furfural in Aqueous Biphasic Systems: A COSMO-RS Guided Approach to Greener Solvent Selection.

5-Hydroxymethylfurfural (HMF) and furfural (Fur) are promising biobased platform chemicals, derived from the dehydration of carbohydrate feedstocks, normally conducted in an aqueous phase. Plagued by side-reactions in such phase, such as the rehydration to levulinic acid (LA) and formic acid (FA) or self-condensation to humins, HMF and Fur necessitates diversification from monophasic aqueous reaction systems toward biphasic systems to mitigate undesired side-reactions. Here, a methodology based on the COnductor-like Screening MOdel for Real Solvents (COSMO-RS) method was used to screen solvent candidates based on the predicted partition coefficients (Ki). Hansen solubility parameters in conjunction with excess thermodynamic quantities determined by COSMO-RS were employed to assess solvent compatibility. Experimental validation of the COSMO-RS values highlighted only minor deviations from the predictions with root-mean-square-error (RMSE) values of HMF and Fur at 0.76 and 5.32, respectively, at 298 K. The combined effort suggested cyclohexanone, isophorone, and methyl isobutyl ketone (MIBK) as the best candidates. Finally, extraction solvent reuse demonstrated cyclohexanone suitability for HMF extraction with KHMF of 3.66 and MIBK for Fur with KFur 7.80 with consistent partitioning across four total runs. Both solvents are classified as recommended by the CHEM21 solvent selection guide, hence adding to the sustainability of the process.

Insights into application of aqueous biphasic systems of deep eutectic solvents composed of benzyltrialkylammonium chloride in dye separation

Deep eutectic solvents (DES) are considered the newest entry in the list of green solvents and they are analogues of ionic liquids (ILs), with excellent solvent characteristics better than commonly used organic solvents and ILs. Owing to this, We have prepared DES using benzyltrialkylammonium chloride (BTAAC) including benzyltrimethylammonium chloride (BTMAC), benzyltriethylammonium chloride (BTEAC), and benzyltributylammonium chloride (BTBAC) as hydrogen bond acceptors (HBA) and glycols, like ethylene glycol (EG), diethylene glycol (DEG) and triethylene glycol (TEG) as hydrogen bond donors (HBD). Aqueous biphasic systems (ABS) were developed using the synthesized DESs and K3PO4, K2HPO4, and K2CO3 at 298.15 K and atmospheric pressure. The phase-forming ability of DES has been evaluated based on the nature of potassium salts, HBA and HBD. In most cases, the influence of salts on ABS formation was found to follow the order: K3PO4 > K2HPO4 > K2CO3, while HBAs follow: BTBAC > BTEAC > BTMAC. The performance of the ABSs was experimentally applied for the extraction of Methyl orange (MO), Eriochrome black T (EBT), and Eosin Y (EY). In most ABS, the extraction order for the studied dyes noticed was: MO < EBT < EY, consistent with their hydrophobic nature. ABS consisting of BTBAC:TEG + K2HPO4 and BTBAC:TEG + K3PO4 was found to lead to the complete extraction of MO, EBT, and EY. The recovery of extracted EY dye was performed by adsorption method using starch-modified chitosan as an adsrobent.

Water Film Structure and Wettability of Different Quartz Surfaces: Hydrogen Bonding Across Various Cutting Planes.

Quartz is ubiquitous in subsurface formations. The crystal faces have different atomic arrangements. Knowledge of the molecular structures on the surface of quartz is key in many processes. Molecular dynamics simulations are conducted to investigate the atomic arrangement effect on the water film structure, ion adsorption, and wettability at three different α-quartz surfaces. The interfacial structures depend on the quartz surface. Intrasurface hydrogen bonding between surface silanols differs in the α-quartz surface. At the (0001) surface, the OH density is 9.58 nm-2, consisting of Q2 units with two hydroxyl groups per silicone atom. At the (101̅0)-β surface, the OH density is 7.54 nm-2, consisting of Q3 units with one hydroxyl group per silicone atom; there is significant intrasurface hydrogen bonding. At the (101̅0)-α surface, the OH density is 7.54 nm-2, consisting of Q2 units; however, there is little intrasurface hydrogen bonding. The intrasurface hydrogen bonding results in the exposure of hydrogen-bond acceptors to the aqueous phase, causing water molecules to have an H-up (hydrogen toward surface) orientation. This orientation can be found at the (0001) and (101̅0)-β surfaces; it is related to the degree of ordering at the surface. The ordering at the (0001) and (101̅0)-β surfaces is higher than that at the (101̅0)-α surface. In aqueous systems with ions, cation adsorption is the most dominant at the (0001) surface due to the largest surface density of the intrasurface hydrogen bonding, providing interaction sites for cations to be adsorbed. We observe a pronounced decrease in water film thickness from the ions at the (0001) surface only, likely due to significant cation adsorption. In this work, we demonstrate that the hydrogen-bond network, which varies from the plane cut, affects the water film structure and ion adsorption. The contact is nearly zero despite the changes in the film thickness and molecular structure at the temperature of 318 K.