The electrochemical corrosion inhibition performance of Pomelo peel extract (PPE) on 304 stainless steel (304SS) in a 1 M hydrochloric acid solution at various temperatures was comprehensively evaluated, alongside its influence on the surface composition and corrosion morphology of 304SS. The results show that PPE contains 15 active ingredients, including citric acid, naringenin, and 3-hydroxyflavone. PPE demonstrates exceptional corrosion inhibition performance for 304SS, achieving a corrosion inhibition efficiency (η) of 94.3% as determined by potentiodynamic polarization tests under optimized conditions of 1.0 g/l PPE at 298 K. The adsorption behavior of the active components on the 304SS surface conforms to the Langmuir isotherm model, with interfacial protection afforded by the formation of a monomolecular layer composed of functional groups, such as C=C, C=O, C=O+, C–N, and C–N+. The surface contact angle of 304SS increases from 73.3° to 92.6°, significantly enhancing its hydrophobicity. Density functional theory and molecular dynamics simulations were employed to elucidate the detailed adsorption mechanism of the active compounds on the 304SS surface. This research confirms that PPE serves as an environmentally friendly corrosion inhibitor for stainless steel, exhibiting significant engineering value due to its highly efficient protective performance and sustainability advantages in acidic media.

Due to its advantages in specific surface area and oxygen-containing functional groups, biochar was often utilized for water pollution control. In this study, biochar was prepared from three types of wetland plants—Lotus Leaf, Arundo donax L., and Canna indica L. through slow pyrolysis. This biochar was utilized to adsorb Cr(VI) from wastewater, and the adsorption performance of the biochar under different pyrolysis temperatures and KOH modification ratios was investigated. The experimental results of biochar preparation demonstrated that under the pyrolysis of 500 °C and the lotus leaf powder/KOH mass ratio of 1:3, the prepared biochar (LBC-500(1:3)) exhibited the optimal adsorption capacity for Cr(VI) at a concentration of 50 mg·L−1, with an adsorption capacity reaching up to 27.88 mg·g−1. The optimal pH for Cr(VI) adsorption by LBC-500(1:3) was 3, with an adsorption capacity of 32.14 mg·g−1 at this pH. When the dosage amounted to 60 mg, LBC-500(1:3) demonstrated its highest adsorption capacity for Cr(VI), achieving a maximum of 19.39 mg·g−1. When the initial concentration peaked at 80 mg·L−1, the adsorption capacity was able to attain a value of 34.80 mg·g−1. Characterization analyses of the biochar prior to and subsequent to adsorption were conducted to elucidate the adsorption mechanisms of biochar for Cr(VI). The results revealed that the primary removal mechanisms of LBC-500(1:3) for Cr(VI) were coordination, electrostatic adsorption, and pore filling. The analysis of adsorption kinetics and isotherms revealed that the biochar predominantly adsorbed the Cr(VI) through monomolecular layer chemisorption. Adsorption thermodynamics results demonstrated that the adsorption process of the biochar was a spontaneous endothermic reaction. This study provides new insights and technical support for water pollution control, which holds significant environmental importance and application value.

It has been demonstrated that a monomolecular surface film with semiconducting characteristics forms on an austenitic, corrosion- and heat-resistant chromium–nickel steel with 0.10 wt.% C, 20 wt.% Cr, 9 wt.% Ni, and 6 wt.% Mn (10Kh20N9G6), microalloyed with yttrium, in aqueous 1 M H2SO4. This passive layer exhibits semiconducting behavior, as confirmed by electrochemical impedance and capacitance measurements. For the first time, key electronic parameters, including the flat-band potential, the thickness of the semiconductor layer, and the Fermi energy, have been determined from experimental Mott–Schottky plots obtained for the interphase boundary between the yttrium-microalloyed austenitic Cr–Ni steel (10Kh20N9G6) and aqueous 1 M H2SO4. The results reveal a systematic shift in the flat-band potential toward more negative values with increasing yttrium content in the alloy, indicating a modification of the electronic structure of the passive film. Simultaneously, a decrease in the Fermi energy is observed, suggesting an increase in the work function of the metal surface due to the presence of yttrium. These findings contribute to a deeper understanding of passivation mechanisms in yttrium-containing stainless steels. The formation of a semiconducting passive film is essential for enhancing the electrochemical stability of stainless steels, and the role of rare-earth microalloying elements, such as yttrium, in this process is of both fundamental and practical interest.

Recovery of rare earth elements (REEs) from industrial waste is a glorious channel for waste to resource transformation. Herein, Zn-BDC-graphene oxide composite (Zn-BDC@GO) was crafted via combining terephthalic acid ligand (BDC) coordinated to Zn2+ center (Zn-BDC) and graphene oxide (GO) to recover Pr(III) from aqueous solution. Recovery performance was optimized using response surface methodology (RSM). Speciation resolved adsorption mechanism was clarified via amalgamating Zn-BDC@GO and Pr(III) speciation, statistical thermodynamics, isotherms and kinetics, as well as multifarious spectroscopy. Result delivers, Zn-BDC@GO renders Pr(Ⅲ) recovery efficiency superior to either GO or Zn-BDC. The maximum mono layer adsorption capacity given by the Langmuir model is 436.68 mg·g− 1 at pH 6, dosage 500 mg·L− 1 and contact time 60 min. RSM clarifies the optimum Pr(III) recovery percent as 99.583% under pH 6.852, Zn-BDC@GO dosage 582.197 mg·L− 1 and contact time 54.017 min. Moreover, Zn-BDC@GO can effectively recover Pr(Ⅲ) from binary lanthanides Pr/Sm, Pr/Eu, Pr/Gd with high selectivity coefficient 24.74, 60.46, 122.77, respectively, exhibiting exceptional selectivity. Statistical thermodynamic functions including enthalpy, Gibbs free energy, entropy, etc., unveil that adsorption is exothermic, spontaneous and randomness increasing. Isotherm and kinetic fittings uniformly designates favorable chemisorption controlled by surface reaction. Speciation and versatile spectroscopy (FTIR, Raman, fluorescent, XPS) reveal that Pr(Ⅲ) is attached to COO, C-O-C, C-C and C = C mainly in the form of Pr3+ via electrostatic attraction and electron transfer to yield maximum adsorption at pH = 6. This work illuminates the adsorption behaviour and mechanism of Pr(Ⅲ) over Zn-BDC@GO, as to shed light on developing MOFs based materials for REEs recovery.

Achieving a high degree of structural ordering in monolayers of disc-shaped molecules, typically comprising large aromatic cores and flexible alkyl chains, is exceptionally challenging yet essential for developing functional materials in organic electronics and optoelectronics. Here, we present a strategy, solely based on supramolecular nanoarchitectonics, wherein a careful molecular design combined with tailored self-assembly pathways enables precise control over molecular ordering. Using ambipolar amphiphilic heterocoronene derivatives, we demonstrate the ability to direct either face-on or edge-on alignment at interfaces. Incorporation of oxadiazole linkers between the heterocoronene core and peripheral alkyl chains yields mechanically robust, hydrophilic, and atomically smooth monolayers with face-on orientation, in sharp contrast to the hydrophobic, edge-on alignment observed for the parent heterocoronene lacking these linkers. The markedly enhanced elastic modulus and surface potential of the oxadiazole-functionalized monolayers at the air-water interface arise from in-plane dipolar reorganization driven by mesoscopic restructuring, as supported by joint analysis of surface-pressure and surface-potential isotherms and corroborated by atomic force microscopy measurements. These findings establish a molecular design principle for engineering cooperative dipolar alignment in two-dimensional organic architectures, offering guidelines for nanoarchitectonic control in monomolecular films and providing pathways toward emerging technologies including organic ferroelectrics, dipolar electronics, and quantum-responsive interfaces.

Brewster angle microscopy (BAM) is a highly surface-sensitive, noninvasive technique used to study the reflectivity and lateral domain structures of Langmuir monolayers at the air-water interface. This experimental system uniquely allows for the control of lateral compression while simultaneously measuring surface pressure and visualization of domains. The primary advantage of BAM over other methods is its ability to directly measure in situ the intrinsic properties of samples without requiring chemical modifications, external probes or further manipulations like transfer to a solid support. This chapter outlines the basic theory of BAM and introduces a new method for determining the refractive index of the monolayer, a key parameter often missing in data analysis. By combining the refractive index with reflectivity measurements, it becomes possible to calculate the thickness of films as a function of lateral packing in lipid, protein, and lipid/protein films.

A series of organic compounds (a) methyl 3-nitro-2-methoxybenzoate, (b) 2,4-dibromoaniline, (c) 2,4-dimethylbenzoic acid, and (d) 5-phenylpentanoic acid, available in certain research laboratories, were systematically studied for their potential application in organic–inorganic hybrid perovskite solar cells. To evaluate their suitability as additive or Self Assembled Mono layer (SAM as HTL), the compounds were characterized using multiple analytical techniques such as X-ray Powder Diffraction (XRD) to determine crystalline structure, Fourier Transform Infrared (FTIR) spectroscopy to study functional group interactions and the presence of hydrogen bond, Scanning Electron Microscopy (SEM) to analyze surface morphology, and UV–Visible spectroscopy to evaluate optical properties such as absorption, refractive index, band gap energy and optical conductivity. The results obtained from these analyses were used to assess the compatibility of the compounds with perovskite materials, particularly their ability to improve film morphology, enhance interfacial interactions, and contribute to the overall stability and efficiency of perovskite solar cell devices.

Bipolar transistors are the main element base in electronics. The development of this base was carried out mainly through experimentation. To justify the operation of the transistor, qualitative representations were used in the form of a double р–n junction of the р–n–p or n–p–n conductivity type. With this justification, many properties of a working semiconductor transistor remained beyond their clear understanding. Therefore, in this paper, the design of a bipolar transistor is considered, taking into account the structure of the solid body of the semiconductor base and the interaction of atoms in the form of negative ions with the surface of the solid body. Based on the analysis of data obtained by a tunneling microscope, the surface of the solid is covered with a monomolecular film, and the crystal of the semiconductor base itself is formed by positively charged atoms and is located under the monomolecular film. The molecular film is formed by surface clusters, and the crystal is formed by volume clusters. The interaction of surface clusters creates a porous structure of the molecular film. Through these pores the crystal of the solid body is visible. Impurities in the form of individual molecules penetrate the surface of the crystal through holes in the molecular film, formed in the form of columnar voids. On the surface of the crystal, impurity molecules, as a result of exchange interaction, dissociate into individual atoms, which in turn, also as a result of exchange interaction, are converted into negative ions. The doping of the surface of a semiconductor crystal of germanium or silicon with arsenic and indium molecules is specifically considered. After the molecules disintegrate into atoms in the columnar voids, they are converted into negative ions, which block the penetration of other molecules into these voids.

The article proposes the author's method for assessing the characteristics of the capillary-porous structure of cement stone and concrete, including: determining the amount of non-evaporating water, the capacity of the monomolecular adsorbate layer Vm and the specific surface of the material S, determining the volume of pores in cement stone and concrete. The results of determining the porosity of concrete are presented taking into account high-temperature heating. Recommendations are given for calculating the integral, differential porosity, pore area and specific surface of heat-resistant concrete.

Biochar is an excellent adsorbent for organic pollutants, but the removal effect for inorganic phosphorus is not satisfactory. In order to improve its phosphorus removal effect, ZnAl-LDH modified plane trees’ bark biochar was presented in this paper. The plane trees’ bark biochar was prepared by chemical-activation method by utilizing K2CO3 as the activation agent. And then, ZnAl-LDH modified biochar was prepared by in-situ co-precipitation method with ammonia as the precipitate agent. As the sample was as little as 10 mg, the adsorption ratio was about 93% for the 25 mL of 20 mg/L PO43−. The saturated adsorption capacity for PO43− was 103.1 mg/g, calculated by Langmuir equation, revealing the adsorption was mainly mono-molecular layer adsorption. The possible adsorption mechanism of phosphate mainly contained interlayer anion exchange, surface complexion and ligand exchange. Moreover, the absorbed sample were soaked in 5.5% Na2CO3 solution for phosphate desorption, nearly 60% of the absorbed phosphate could be recovered and may reuse in the future.

Boric acid/β-CD-based polymers (BA-CD) possess hierarchical porous structures and efficient functional groups for further molecular recognition, which are used for the adsorption of a series of cationic and anionic organic dyes. The effects of pH, contact time, initial concentration of solution, and temperature on the adsorption performance were experimentally investigated in detail. Surprisingly, the adsorption capacities of BA-CD towards RB exhibited a higher value of 733.2 mg g−1 among a series of cationic and anionic dyes. The adsorption kinetics further indicated that the adsorption of dyes by BA-CD belonged to a quasi-second-order kinetic model, while the adsorption isotherms demonstrated the adsorption process as the Langmuir isotherm model. The characterization of the adsorption process was performed in the presence of monomolecular layer chemisorption. In addition, the reusability test showed that BA-CD had a high reusability rate of 90% in MG after five cycles, indicating its future potential for the treatment of dye wastewater.

Highly Sensitive Plasmonic Sensors Based on Silicon and Nitrides of Si and Ga on Mono and Bimetallic Layers for Biomedical Applications

Anomalous long- and short-scale behavior of DNA conformation on a highly charged monomolecular film at different ionic strength.

Analytical expressions for the low-field mobility of the two dimensional electrons in mono layer graphene are obtained on base of quantum kinetic approach that is based on the one-particle density matrix and the model non-equilibrium distribution function in form of the shifted Fermi distribution. We consider the gated graphene with the Fermi level that is biased by applying an external voltage to the gate. In this case, the confining potential has the shape of a triangle well that can be written in terms of Airy functions. Screened acoustic, optic phonons and ionized impurities are considered as scattering mechanisms. Calculations show that in the semiconductors with Dirac spectrum of charge carriers mobility for scattering by acoustic phonons and ionized impurities does not depend on the electron effective mass. Both effective mass of electrons and scattering rate by non-polar optic phonons reach minimum for electron energy close to the Dirac point. A comparison of the temperature dependences of the calculated and experimental mobility data shows that in the temperature range under consideration, at <I>T </I>< 400 K mobility is determined by the scattering of electrons by ionized impurities. The acoustic and out-of-plane optical phonons (ZO phonons) determine the electron mobility at higher temperatures. Results of mobility calculations are compared with known experimental data.

In this article, we disclose a cinnamate-based compound that contains a phosphonic acid group, serving as a photoalignment layer for liquid crystals. The proposed alignment material demonstrates a strong affinity for various metal oxides due to the presence of phosphonic acid as an anchoring group. It can be applied to an ITO-coated glass substrate through a dip-coating technique, followed by a washing process. These photoalignment materials can form a monomolecular layer that demonstrates effective alignment when irradiated with polarized light. These materials are characterized by high anchoring energy, a high voltage holding ratio, and low residual direct current, offering both planar and vertical alignment of nematic liquid crystals depending on their molecular structure. This alignment technique is suitable for displays and other photonic devices that can be fabricated on flexible and solid substrates. Additionally, the dip-coating method simplifies the fabrication process by eliminating the complex and energy-intensive hard baking typically associated with conventional polyimides (PIs). As a result, this can significantly reduce fabrication costs and the carbon footprint for display production lines.

Abstract Bentonite plays a significant role as a buffer backfill material in geological disposal due to its unique properties that are crucial for the safe containment of high-level radioactive waste. In this work, the impact of various factors on the adsorption of selenite (Se(IV)) by both calcium-based and sodium-based bentonite was examined using batch experiments. As a result, both types of bentonite achieve adsorption equilibrium with Se(IV) within approximately 120 h. The adsorption capacity decreases with increasing initial concentration of Se(IV), while it is positively influenced by longer contact times and higher temperatures. The partition coefficient ( K d ) exhibits a complex relationship with pH, initially decreasing, then increasing, and finally decreasing again. Additionally, ionic strength significantly affects the adsorption process. These observations suggest that Se(IV) adsorption on bentonite is pH-dependent and involves a non-spontaneous heat-absorbing process, likely a chemical reaction dominated by the ion-exchange form of chemisorption in a monomolecular layer. This process aligns well with the isothermal adsorption model and the simulated secondary kinetics of the Langmuir model. Furthermore, the adsorption of Se(IV) is notably hindered by the increased electrostatic repulsion between the negatively charged bentonite surface and the negatively charged species HSeO 3 2− and SeO 3 2− . The Fourier transform infrared spectra showed that the positions, intensities and shapes of the spectral characteristic peaks of the functional groups before and after adsorption did not change significantly.

Spinel type LiNi0.5Mn1.5O4 (LNMO) is expected as a 5 V class cathode material which brings about high energy density of lithium ion secondary battery. In contrast to widely used 4V class layered cathode material, the capacity degradation due to oxidative decomposition of electrolyte during charging was seriously affecting the cyclability. We have demonstrated the suppression of oxidative decomposition reaction of electrolytes from the viewpoint of surface modification of active materials such as fluoroalkylsilane monomolecular film modification, Nb2O5 nanosheet coating, halide and sulufide ion dopings. In particular, LNMO4-xFx (LNMOF) substituted with fluoride ion was found to highly suppress oxidative decomposition of electrolyte without increasing reaction resistance or coating resistance, and was effective for improving cycle characteristics. On the other hand, there was a big drawback that the specific capacity decreased in proportion to the amount of fluoride ion substitution. Fluoride ions preferentially coordinate with Mn3+ to form trans MnO4F2 octahedrons. By the stabilization of Jahnteller strain by Mn3+, the oxidation potential becomes high up to 5.2 V(vs. Li/Li+), and it is clarified that the redox activity is lost depending on the charging upper voltage range. In this study, we synthesizedLiNi0.5Mn1.5O4-x F x (LNMOF) cathode materials containing cis- or trans-form F-Mn-F local configuration in MnO4F2 octahedra, and characterization of their structural and electrochemical properties. In the cis-LNMOF, the decrease in specific capacity due to fluorine substitution observed in the trans-LNMO with the trans configuration was significantly suppressed, and it was consisting with the results of DFT calculations. Furthermore, the cis-LNMOF provided outstanding C rate capabilities and cyclabilities.

Novel honeycomb 3D Co/In-MOF with rigid ligand are used for efficient C1-C3 light hydrocarbons adsorption separation, fluorescence sensing and selective dye adsorption

The hygroscopicity of building materials directly influences their thermal insulation performance, which is critical for achieving energy efficiency. Conventional materials, however, are limited by high moisture absorption, flammability, and poor thermal stability, rendering them inadequate for modern energy-saving needs. In this study, hydrophobic SiO 2 aerogel was incorporated into cement-based matrices to fabricate SiO 2 aerogel cement-based insulation boards (AIC) with enhanced thermal insulation properties. The investigation focused on how varying hydrophobic SiO 2 aerogel (SA) concentrations (0–50 vol%) affect the hygroscopic behavior of AIC under relative humidity (RH) conditions ranging from 0% to 95%. Furthermore, an isothermal adsorption model for moisture in SA cement-based materials was also established. Experimental results showed that under low to moderate humidity (RH ≤ 50%), the hygroscopicity of AIC was proportional to the SA concentration. At RH 30%, the water content increased from 1.25% in AIC0 (0 vol% SA) to 1.46% in AIC50. When RH exceeded 50%, 30 vol% SA marked the threshold between moisture absorption and hydrophobicity. When SA concentration was below 30 vol%, the hygroscopicity of AIC increases. At RH 70%, AIC20 had a water content of 6.67%, a 21% increase over AIC0 (5.51%). When SA concentration was above 30 vol%, the hydrophobicity of AIC is enhanced. At RH 95%, AIC40 showed a water content of 10.85%, a 20% reduction compared to AIC0 (13.5%). In addition, the hygroscopic equilibrium process of AIC was divided into three stages: the slow growth of monomolecular layer adsorption, the steady-state growth of multimolecular water film formation, and the rapid growth of capillary adsorption. For the first time, the Lewicki model is validated for hydrophobic composites, achieving exceptional accuracy (R 2 > 99%, SSE: 0.001–0.204, RMSE: 0.0002–0.2032) by integrating SA-induced pore coarsening and hydrophobic effects. These findings provide a theoretical foundation and data support for the application of AIC in diverse humidity environments.

This study analyzed the compression isotherms of 7β-alkyl cholic acid derivatives and compared them to those of cholic and deoxycholic acids to elucidate their orientation and molecular interactions (acidic aqueous substrate-pH 2; NaCl concentration-3 M; temperature-T = 298.15 K). It was found that the compression isotherm of the 7β-octyl derivative of cholic acid in the monomolecular layer is most similar to the compression isotherm of deoxycholic acid. In 7β-alkyl derivatives of cholic acid, the hydrophobic interaction energy in their aggregates from a monomolecular film increased with the length of the alkyl chain. However, this energy did not increase linearly with C atoms, suggesting the existence of a conformational equilibrium. In binary mixtures of the tested bile acids and lecithin, only the 7β-octyl derivatives of cholic acid and deoxycholic acid had orientations in which the steroid skeleton had a "vertical" position, i.e., only the C3 OH group was immersed in the aqueous substrate, which resulted in the maximum hydrophobic interaction with lecithin. In 7β-octyl derivatives, part of the octyl chain probably also participated in the interaction with lecithin. In 7β-propyl and 7β-butyl derivatives, C7 alkyl groups sterically shielded the C7 α-axial OH group. However, in the 7β-ethyl derivative the C7 OH group was not additionally sterically shielded, so this derivative, similarly to cholic acid, partially dissolved in the aqueous substrate after the collapse point.