Langmuir [JOURNAL]
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200 papers
Spin Dewetting of Ultrathin Polymer Films.
Das A, Bhandaru N, Ritanjali SR … +1 more , Mukherjee R
Langmuir · 2026 Jul · PMID 42388120 · Publisher ↗
Spin coating is a very well-established technique for creating ultrathin films of polymers, colloids, sol-gel devices, inorganic materials, and so on. However, it is often observed that when a very dilute polymer solutio...
Spin coating is a very well-established technique for creating ultrathin films of polymers, colloids, sol-gel devices, inorganic materials, and so on. However, it is often observed that when a very dilute polymer solution over a defect-free, flat substrate is spin-coated, a continuous film does not form. Generally, this is attributed to defects on the surface, which are likely to result in patchy deposition. However, we show that an isotropic array of nearly equal-sized polymer droplets spanning over the entire substrate forms, right after spin coating of an extremely dilute solution, in a reproducible manner, which cannot be due to the existence of any surface defects. We argue that this happens due to spontaneous instability and subsequent dewetting of the casting solution during rotation due to the Marangoni effect and term the phenomenon as spin dewetting. We report the effect of parametric variation on spin dewetting and show, among other results, that the feature size () and periodicity (λ) of the droplets reduce with an increase in the concentration of the casting solution (). Based on our observations, we argue that spin dewetting is strongly influenced by evaporation-mediated Marangoni stress, which is in clear contrast to disjoining pressure-mediated dewetting of thin polymer films. As the patterns form during spin coating itself, the technique can be used as a rapid, ultrafast meso-patterning technique with excellent reproducibility.
Comment on "The Origin of Surface Energy of Calcite and Its Wettability".
Bruno M
Langmuir · 2026 Jul · PMID 42387976 · Publisher ↗
Abstract loading — click title to view on PubMed.
Multivalent-Anion-Induced Inversion of Chiroptical Signals in a Cyanine Dye Bound to Nanotubular Supramolecular Assemblies.
Otsuki M, Hano N, Ihara H … +1 more , Takafuji M
Langmuir · 2026 Jul · PMID 42387838 · Publisher ↗
In this study, we investigated the effect of salts on the induced chirality of the cyanine dye NK2707 when bound to supramolecular assemblies formed by cationic glutamide lipids (G-Py). NK2707 bound to G-Py self-assemble...
In this study, we investigated the effect of salts on the induced chirality of the cyanine dye NK2707 when bound to supramolecular assemblies formed by cationic glutamide lipids (G-Py). NK2707 bound to G-Py self-assembled structures formed diverse aggregates and exhibited exceptionally large circular dichroism (CD) signals. The -aggregates of NK2707 showed an unusually intense -chiral-induced CD signal attributable to Davydov splitting; this signal reversed to an -chiral CD response upon addition of the sodium salt of a multivalent anion. This inversion of a CD signal at the 10 level is unprecedented. In contrast, NaCl addition produced no appreciable spectral change, suggesting that this effect strongly depends on anion valence. We attribute the CD inversion to multivalent-anion bridging of pyridinium groups, which alters and stabilizes the chiral orientation of G-Py and, in turn, reverses the induced CD. Furthermore, although molecular orientation typically decreases above the gel-liquid-crystal phase transition temperature, NaSO addition enabled G-Py to retain its chiral orientation even in the liquid-crystal state. NaSO promoted -aggregate formation in the gel state and -aggregate formation in the liquid-crystal state, maintaining a CD peak on the order of 10 while shifting the wavelength by approximately 200 nm. Overall, the G-Py/NK2707 system can be dynamically modulated by multivalent anions and temperature, providing a versatile platform for controlling chiroptical properties through salt-induced changes in molecular orientation.
Adsorption Behavior and Molecular Interaction Mechanism of AMPS-Copolymer/HEDP Complex Retarder on Hydration of Tricalcium Silicate (CS) in Oil Well.
Huang S, Sun D, Li Z … +2 more , Liu X, Su D
Langmuir · 2026 Jul · PMID 42385719 · Publisher ↗
Hydroxyethylidene diphosphonic acid (HEDP) is used as an auxiliary material for AMPS (2-acrylamido-2-methylpropanesulfonic acid) copolymer retarders because of its good water solubility and high temperature resistance. T...
Hydroxyethylidene diphosphonic acid (HEDP) is used as an auxiliary material for AMPS (2-acrylamido-2-methylpropanesulfonic acid) copolymer retarders because of its good water solubility and high temperature resistance. This paper investigates how the presence of HEDP significantly enhances the inhibitory effect of AMPS copolymers (PAIND) on cement hydration, focusing on adsorption behavior and interfacial interactions. The adsorption capacity, adsorption thickness and interface interaction were characterized by total organic carbon, ζ-potential, X-ray photoelectron spectroscopy (XPS) and molecular dynamics simulation. Adsorption behavior experiments revealed that the PAIND/HEDP complex retarder exhibited higher adsorption capacity and a thicker adsorption layer on CS surfaces compared to individual PAIND or HEDP. HEDP may enhance the overall adsorption capacity of the system and increase the thickness of the adsorption layer by filling the vacant adsorption sites at the PAIND-CS interface. Interfacial interaction analysis reveals that in PAIND, increasing HEDP content enhances the adsorption of the PAIND/HEDP complex retarder onto CS, resulting in reduced conformational changes and a more stable adsorption layer. This is primarily attributed to a robust network structure formed via multiple chemical interactions─including hydrogen and ionic bonds─between the retarder and CS, which strengthens inhibition of CS hydration under extreme high-temperature conditions.
Size- and Geometry-Dependent pH-Responsive Nanochannel Membranes Functionalized with Glycine and Pentylamine.
Cao S, Assadipapari M, Xu Y … +9 more , Liu Y, Yu M, Peng J, Xiao L, Yang Y, Cai Y, Balme S, Cao Z, Ma T
Langmuir · 2026 Jul · PMID 42384907 · Publisher ↗
Artificial membranes are widely used to mimic the selective transport behavior of biological ion channels and pumps, particularly their stimulus-responsive regulation capabilities. Herein, solid-state nanochannels are ch...
Artificial membranes are widely used to mimic the selective transport behavior of biological ion channels and pumps, particularly their stimulus-responsive regulation capabilities. Herein, solid-state nanochannels are chemically functionalized with glycine (Gly) and pentylamine to precisely tune interfacial chemistry and surface charge states. Owing to distinct pore sizes and geometric confinement, cylindrical and conical nanochannels exhibit markedly different pH-responsive ion transport mechanisms. In cylindrical nanochannels with relatively large diameters, ion transport is dominated by bulk ionic conduction, and the pH dependence mainly arises from the different mobilities of H and OH ions. In contrast, conical nanochannels with narrow tips display surface-charge-governed transport, where pH and salt concentration jointly modulate electric double layer overlap and ion current rectification. Under acidic conditions, the functionalized nanochannels show suppressed ionic conduction associated with a hydrophobic interfacial state, while alkaline environments induce enhanced conduction due to increased surface charge density and wettability. These results establish a geometry-dependent pH-gating mechanism, providing a rational design strategy for responsive ion-transport membranes in sensing and separation applications.
Synergistic Visible-Light-Driven CO Reduction and HO Oxidation over TiC Quantum Dot-Modified Cu/g-CN Photocatalysts.
Ji X, Chen J, Li M … +1 more , Tang J
Langmuir · 2026 Jul · PMID 42384434 · Publisher ↗
Photocatalytic CO reduction into value-added fuels using water as the electron donor represents a sustainable route for artificial photosynthesis, yet it is often hindered by rapid charge recombination and insufficient t...
Photocatalytic CO reduction into value-added fuels using water as the electron donor represents a sustainable route for artificial photosynthesis, yet it is often hindered by rapid charge recombination and insufficient thermodynamic driving force. Herein, we report a ternary heterojunction photocatalyst composed of zero-dimensional TiC quantum dots (QDs) and metallic Cu comodified on two-dimensional g-CN (denoted as CCNT). The Cu nanoparticles broaden the visible-light absorption and negatively shift the conduction band of g-CN, providing a strong driving force for CO reduction. Meanwhile, the highly conductive TiC QDs act as efficient electron reservoirs, rapidly extracting photogenerated electrons from Cu/g-CN and redistribute photogenerated electrons. This prevents charge accumulation at Cu sites, stabilizes the reduction centers, and maintains electron-hole balance. The optimized CCNT-5 composite achieves CO and CH production rates of 24.59 and 20.24 μmol g h under visible light, resulting an electron selectivity toward CO reduction as high as 94.90%. Moreover, the catalyst enables simultaneous water oxidation with a nearly 1:1 electron-to-hole consumption ratio and excellent long-term stability. This work demonstrates a rational 0D/metal/two-dimensional (2D) architecture for efficient and stable solar-driven CO reduction.
Spontaneous Phase Separation Enables Rapid, Polymerization-Free Fabrication of Gels.
Priyadarshinee N, Saxena V, Kambekar A … +2 more , Chauhan G, Pushpavanam K
Langmuir · 2026 Jul · PMID 42384396 · Publisher ↗
Hydrogels are cross-linked polymeric networks with wide applications in drug delivery, tissue engineering, biosensing, and environmental remediation. These hydrogels additionally host living cells, small molecules, and b...
Hydrogels are cross-linked polymeric networks with wide applications in drug delivery, tissue engineering, biosensing, and environmental remediation. These hydrogels additionally host living cells, small molecules, and biological propagules, which further expand the applications of these materials. However, most, if not all, fabrication methods require covalent modifications. In this work, by deliberately selecting polymers with a known propensity to phase separate and formulating compositions far from the binodal boundary, we demonstrate the propensity of the system to transition directly into viscoelastic liquids or gels. This behavior is demonstrated using a model system of poly(ethylene glycol) (PEG) and dextran (DEX). We carried out rheological studies to provide insights into the viscoelastic behavior of these gels. We systematically characterized the gels through colorimetric assays, FTIR, MALDI-TOF, and thermogravimetric analysis (TGA) to discern the molecular compositions and solvent content of the gels. These experimental findings are supplemented with coarse-grained (CG) simulation insights to investigate the mechanistic origins of phase separation propensity with varying molecular weights of DEX. We utilized coexisting densities in the two phases using CG simulations to predict the role of DEX molecular weight in the partitioning of PEG and DEX in the two phases. Finally, we exploit the fabricated gel's ability to encapsulate live cells, antibiotics, and plant seeds. We anticipate that this ATPS-based fabrication technique will provide a scalable, cross-linker-free route to multifunctional gels, enabling advanced applications in drug delivery and responsive materials.
Lamellar-Confinement-Induced ZIF-67 Nanosheet Mixed Matrix Membranes for Enhanced CH/N Separation.
Li D, Yin S, Ding L
Langmuir · 2026 Jul · PMID 42383880 · Publisher ↗
The development of high-performance mixed-matrix membranes (MMMs) for gas separation is frequently constrained by the poor interfacial compatibility between traditional isotropic metal-organic framework (MOF) fillers and...
The development of high-performance mixed-matrix membranes (MMMs) for gas separation is frequently constrained by the poor interfacial compatibility between traditional isotropic metal-organic framework (MOF) fillers and polymer matrices. To address this limitation, this study introduces a lamellar-confinement strategy for synthesizing two-dimensional ZIF-67 nanosheets (ZIF-67) using a cetyltrimethylammonium bromide (CTAB) liquid crystal template, which effectively restricts crystal growth along the -axis and promotes lateral expansion. Notably, water serves as a cosolvent for both the CTAB liquid crystal templating system and ZIF-67: this dual role not only facilitates the self-assembly of CTAB molecules into an ordered liquid crystal phase, but also modulates the coordination of Co/2-methylimidazole and the nucleation kinetics of ZIF-67, thereby synergistically promoting the oriented growth of 2D nanosheets. The resulting nanosheets exhibit high crystallinity, a well-defined hexagonal morphology with an average thickness of 44.3 nm, and a high specific surface area of 1029.3 m/g. Upon incorporation into a styrene-ethylene-butylene-styrene (SEBS) copolymer matrix, the ZIF-67 significantly enhance the polymer-filler interfacial contact area. The fabricated MMMs demonstrate a dramatic improvement in CH permeability, increasing from 24.3 to 278.4 barrer at a 30 wt % loading─an enhancement of approximately 1050%, while maintaining a CH/N selectivity of 5.15. This study suggests the significant potential of morphology-controlled two-dimensional MOFs for constructing highly efficient gas separation membranes.
Structure Control of Oblate Nanoparticles Self-Assembled by ABC Cyclic Terpolymers under Soft Confinement.
Xu G, Song T, Han Y … +1 more , Cui J
Langmuir · 2026 Jul · PMID 42383877 · Publisher ↗
The self-assembly behavior of cyclic ABC terpolymers under 3D soft confinement were studied using Monte Carlo simulation. The simulation results indicate that under neutral boundary conditions, the cyclic ABC terpolymers...
The self-assembly behavior of cyclic ABC terpolymers under 3D soft confinement were studied using Monte Carlo simulation. The simulation results indicate that under neutral boundary conditions, the cyclic ABC terpolymers self-assemble into nanoparticles with intriguing ordered inner nanostructures, i.e., each component forms hexagonally packed short cylinders arranged in the nanoparticles. It is worth noting that the overall shape of those nanostructured particles can be tuned via changing the interfacial interactions between different blocks (ε) and the interfacial interactions between the terpolymers and solvents (ε), and the nearly flat oblate nanoparticles can be obtained in the case of large ε while small ε. In addition, via changing the confinement degree, the number of short cylinders in the particles can be easily tuned, which leads to the formation of oblate nanoparticles with various internal nanostructures, and core-multi-petal oblate nanoparticles with one component forming the core and the other two components forming the petals can be obtained when the confinement degree is relatively strong. It should be noted that the core-forming component in the core-multi-petal nanoparticles can be easily tuned via introducing the selectivity of the solvents. Our simulation results indicate that the cyclic ABC terpolymers is a good candidate for the preparation of oblate nanoparticles with controllable inner nanostructures.
Tuning Brønsted/Lewis Acid Site Ratios via Ammonia Modulation for Selective Conversion of Glycerol to 1,3-Propanediol or Solketal.
Fan X, Xu M, Tang Z … +4 more , Zhang L, Liu J, Li Y, Wang F
Langmuir · 2026 Jul · PMID 42383384 · Publisher ↗
In this study, two different ferric hydroxyphosphate (FHP and FHP-B) catalysts, synthesized by the same procedure with or without the addition of aqueous ammonia have shown excellent performance in the hydrogenolysis of...
In this study, two different ferric hydroxyphosphate (FHP and FHP-B) catalysts, synthesized by the same procedure with or without the addition of aqueous ammonia have shown excellent performance in the hydrogenolysis of glycerol to 1,3-propanediol (1,3-PDO) (conversion of glycerol: 60.7%; selectivity of 1,3-PDO: 87.9%) and acetalization of glycerol to solketal (conversion of glycerol: 94.9%; solketal selectivity: 98.3%). Simultaneously converting glycerol to two high-value-added chemicals is of great significance. Meanwhile, the two catalysts are characterized by a series of instruments, and the results show that the addition of aqueous ammonia alters the concentration of Brønsted and Lewis acidic sites of the catalysts, thus allowing them to attack different hydroxyl groups on glycerol. The Brønsted acid sites (BAS) of the FHP catalyst without the addition of aqueous ammonia were more selective for the breaking of the 2°-OH bond, whereas the FHP-B catalyst, due to the presence of aqueous ammonia, converted some BAS to Lewis acid sites (LAS) during the synthesis process. A large amount of LAS was inclined to attack glycerol's 1°-OH bond, which is more favorable for the condensation reaction of glycerol and acetone. This finding innovatively provides a new strategy for the catalyst synthesis and a new perspective on reaction mechanism research.
Catalytic and Nitriding Competition of Nitrogen Atom on Graphene and Its Finite Rate Surface Chemistry Model.
Gao Y, Meng S, Gao B … +2 more , Yang Q, Yang F
Langmuir · 2026 Jul · PMID 42381625 · Publisher ↗
Gas-surface interactions during hypersonic atmospheric reentry remain incompletely understood, particularly with respect to the catalytic recombination and nitridation of nitrogen atoms on carbon-based thermal protection...
Gas-surface interactions during hypersonic atmospheric reentry remain incompletely understood, particularly with respect to the catalytic recombination and nitridation of nitrogen atoms on carbon-based thermal protection materials. In this study, reactive molecular dynamics (RMD) simulations were employed to investigate the temperature-dependent transition of dominant reaction pathways on graphene surfaces over the range of 900-4000 K. Below 1400 K, catalytic recombination dominates, and nitrogen atoms mainly contribute to heat transfer through Eley-Rideal (E-R) and Langmuir-Hinshelwood (L-H) pathways. At intermediate temperatures (1400-2500 K), catalytic recombination and nitridation proceed concurrently, accompanied by progressive graphene decomposition. Above 2500 K, nitridation becomes dominant and results in substantial CN formation. A finite-rate surface chemistry model developed from the RMD data yields activation energies of 27.34 kJ/mol for E-R II and 48.24 kJ/mol for L-H recombination. By identifying plausible catalytic pathways for nitrogen atoms and clarifying the competition between catalysis and nitridation, this work extends the classical C-N reaction models of Park and Zeldovich-Anderson and provides a basis for correcting their tendency to overpredict nitridation rates while underpredicting catalytic reaction rates.
AlV/CuAl Composite Derived from Al-V-Cu Precursors for Enhancing the Hydrogen Storage Properties of MgH.
Jiang M, Ge C, Ma J … +9 more , Zhang Z, Ni C, Kimura H, Hou C, Yang X, Zhang Y, Sun X, Du W, Xie X
Langmuir · 2026 Jun · PMID 42381402 · Publisher ↗
Developing catalysts is an important way to modify the hydrogen storage performances of magnesium hydride (MgH). The hydrogen storage performance of MgH was enhanced by employing a mixture of AlV/CuAl alloy as a catalyti...
Developing catalysts is an important way to modify the hydrogen storage performances of magnesium hydride (MgH). The hydrogen storage performance of MgH was enhanced by employing a mixture of AlV/CuAl alloy as a catalytic additive, which was fabricated via arc melting followed by hydrogen plasma treatment. The as-prepared AlV/CuAl was mechanically added into MgH through ball milling to form MgH- wt % AlV/CuAl composites ( = 2.5, 5, 7.5). Remarkably, the MgH-5 wt % AlV/CuAl composite demonstrated the best performance: desorbing 6.7 wt % hydrogen within 1 h at 598 K, which is 1.9 times faster than pristine MgH under same conditions. Based on kinetic analyses, the activation energy for hydrogen absorption decreased notably to 74.91 kJ/mol, while that for desorption dropped to 150.50 kJ/mol. Furthermore, the composite exhibited exceptional cycling stability, retaining 99% of its initial hydrogen absorption and desorption capacity after 20 cycles. This outstanding reversibility is attributed to the stable dispersion of AlV/CuAl particles, which effectively suppresses the coarsening and agglomeration of Mg/MgH particles. This work offers a feasible approach for designing transition metal alloy catalysts to address the kinetic constraints of metal hydride-based hydrogen storage systems.
Correction to "Lactate Monitoring using Fluorescence with Stable Boronic Acid-Functionalized Nanoparticles from Polymerization-Induced Self-Assembly (PISA)".
Balouchi MH, Liu Z, Ishizuka F … +4 more , Bear JC, Kadri H, Zetterlund PB, Aldabbagh F
Langmuir · 2026 Jun · PMID 42380107 · Publisher ↗
Abstract loading — click title to view on PubMed.
Material Removal Mechanism of Three-Phase Flow in Sapphire Ultrasonic Polishing: Insights from the Dense Discrete Phase Model and Polishing Experiments.
Zhou M, Zhong M, Xu C … +3 more , Wan Y, Hu R, Xu W
Langmuir · 2026 Jun · PMID 42378492 · Publisher ↗
Ultrasonic vibration affects three-phase flow behavior under the hydrodynamic contact mode in sapphire ultrasonic vibration chemical mechanical polishing (UVCMP). Nevertheless, the effects of slurry dynamics on material...
Ultrasonic vibration affects three-phase flow behavior under the hydrodynamic contact mode in sapphire ultrasonic vibration chemical mechanical polishing (UVCMP). Nevertheless, the effects of slurry dynamics on material removal remain unclear due to challenges in experimental characterization. In this paper, the influences of key factors on the material removal of three-phase flow were investigated via the dense discrete phase model. The simulation results reveal that concentration and particle size present insignificant impacts on the multiphysical fields. However, the shear stress and material removal rate (MRR) increase with the concentration. While shear stress increases by 6 orders of magnitude as abrasive diameter grows from 20 to 5000 nm, the MRR only triples. As the ultrasonic amplitude and frequency rise, the multiphysical fields and shear stress are enhanced. The numerical MRR increases by 59% when the amplitude rises from 1 to 3 μm. The ultrasonic frequency is found to markedly affect the mechanical removal capability of sapphire UVCMP. The gray relational analysis reveals that frequency has the most significant effects on the simulation MRR ( = 0.8608). The influences of various factors on simulation MRR are experimentally validated. This paper establishes a theoretical foundation and provides novel insights for the optimization of sapphire UVCMP.
Polydopamine/Cerium Oxide Nanoparticle Coating on 3D-Printed Photothermal Shape-Memory Bone Scaffolds for Synergistic Antibacterial and Antitumor Applications.
Guo W, Gong Y, Xu C … +7 more , Pang Y, Peng Z, Long Y, Mai H, Wang S, Tao N, Liu J
Langmuir · 2026 Jun · PMID 42378310 · Publisher ↗
Addressing complex bone defects associated with infection and tumors requires advanced surface and biointerface engineering of biomaterials. This study presents a surface functionalization strategy for constructing a mul...
Addressing complex bone defects associated with infection and tumors requires advanced surface and biointerface engineering of biomaterials. This study presents a surface functionalization strategy for constructing a multifunctional coating on a 3D-printed shape-memory polymer composite (PLA/PEG/MoS) substrate. Utilizing a polydopamine (PD)-mediated deposition process, cerium oxide nanoparticles (CeO NPs) were uniformly immobilized onto the scaffold surface to create a tailored, functionally active coating. This coating markedly altered the surface physicochemical properties, reducing the water contact angle from approximately 81° to 48°, and enhanced interfacial biomineralization and the osteoblastic response of MC3T3-E1 cells. Moreover, the designed substrate-coating architecture integrated bulk photothermal responsiveness with surface-mediated nanoparticle activity, enabling a synergistic therapeutic mode at the biointerface. Under near-infrared (NIR) irradiation, the photothermal heat generated by the MoS-incorporated scaffold triggered shape-memory recovery for adaptive defect fitting while simultaneously amplifying the antibacterial and antitumor efficacy of the PD/CeO coating. As a result, the multifunctional scaffold achieved antibacterial rates of 92% against and 94% against , together with a 92% ablation rate of human osteosarcoma (HOS) cells. Overall, this work demonstrates a potential functional-coating strategy for engineering a multifunctional biointerface on 3D-printed bone scaffolds, integrating surface bioactivity, NIR-triggered shape-memory behavior, and synergistic photothermal/nanoparticle therapy. These findings provide a promising design for functional coatings and surface-engineered biomaterials in the treatment of complex bone defects.
Asymmetric Interfacial Dynamics during Oblique Impact of Two Unequal-Sized Nanodroplets on Superhydrophobic Surfaces.
Liao M, Wang B, Liu Q … +2 more , Hong W, Xie F
Langmuir · 2026 Jun · PMID 42377262 · Publisher ↗
Molecular-level understanding of droplet rebound on nonwetting surfaces is important for controlling liquid transport and removal. In this work, molecular dynamics simulations are used to investigate the oblique impact o...
Molecular-level understanding of droplet rebound on nonwetting surfaces is important for controlling liquid transport and removal. In this work, molecular dynamics simulations are used to investigate the oblique impact of two unequal-sized nanodroplets on a superhydrophobic Pt surface. The effects of Weber number and inclination angle on impact morphology, spreading, rebound, and energy dissipation are systematically examined. With increasing Weber number, the impact outcome evolves from regular deposition to regular bouncing, hole bouncing, and breakup-dominated states. Increasing the inclination angle enhances tangential momentum and impact asymmetry, thereby promoting perforation and fragmentation while reducing the maximum spreading factor. An inclination-corrected scaling relation, sin, better describes the spreading behavior than conventional inclination-independent correlations. Rebound analysis shows that the inclination angle regulates horizontal displacement, restitution coefficient, takeoff velocity, and contact time by altering momentum partition and asymmetric recoil. Energy analysis further indicates that although viscous dissipation increases with Weber number, its proportion relative to the initial kinetic energy decreases. More importantly, the coupling between oblique impact and droplet-size asymmetry activates a rolling-assisted rebound mode, providing an additional route for energy redistribution. These results reveal how dynamic and geometric asymmetries govern nanodroplet mobility on superhydrophobic surfaces.
Anion-Induced Surface Curvature for Modulating Electronic Structures to Enhance Aqueous-Phase C-C Coupling toward Biofuel Precursors.
Zang Z, Zheng F, Yu Y … +2 more , Xu L, Liu G
Langmuir · 2026 Jun · PMID 42376913 · Publisher ↗
The direct synthesis of bioaviation fuel precursors from furfural (FF) aqueous solutions represents a promising and more sustainable approach. Herein, we report MgAlSnO mixed oxides derived from MgAlSn-LDH intercalated w...
The direct synthesis of bioaviation fuel precursors from furfural (FF) aqueous solutions represents a promising and more sustainable approach. Herein, we report MgAlSnO mixed oxides derived from MgAlSn-LDH intercalated with various interlayer anions, exhibiting favorable activity for the aqueous C-C coupling of FF and methyl isobutyl ketone (MIBK). MgAlSnO-CA demonstrates optimal resistance to water poisoning, achieving 96% conversion of FF in high-water-content systems ( = 7). Furthermore, the excellent catalytic activity of MgAlSnO-CA in various aqueous-phase C-C couplings of biomass-derived molecules confirms broad applicability. In situ DRIFTS studies and contact angle measurements reveal that water dissociation enables the catalyst to exhibit superior resistance to water poisoning. Poisoning experiments confirmed that the acidic sites on the catalyst served as the active sites for water dissociation. DFT calculations reveal that the charge density of Sn influences the strength of the p-p orbital, which plays a decisive role in determining the water dissociation rate and water-poisoning resistance. This study provides guidance for the direct resource utilization of FF aqueous solutions and suggests a novel strategy to mitigate the water poisoning of metal oxides.
Impact Dynamics and Heat Exchange of Cold Droplet on Supercooled Macrotextured Nonwettable Surfaces.
Chowdhury NN, Yang Y, Shiri S
Langmuir · 2026 Jun · PMID 42376902 · Publisher ↗
When a water droplet impacts a supercooled surface, it may freeze upon contact and adhere to it. Superhydrophobic surfaces, which repel water, are often used in anti-icing applications due to their ability to reduce ice...
When a water droplet impacts a supercooled surface, it may freeze upon contact and adhere to it. Superhydrophobic surfaces, which repel water, are often used in anti-icing applications due to their ability to reduce ice adhesion by minimizing the contact time and contact area between the droplet and the substrate. However, they can often be ineffective, as ice nucleation may still occur when either the droplet, the surface, or both are supercooled. Here, we demonstrate that adding macrotextures to nonwettable substrates significantly influences droplet surface interactions and alters the freezing dynamics, enabling a shift from full droplet adhesion to partial or even complete rebound, even under supercooled conditions, which is favorable for ice nucleation. By capturing impact dynamics from both side and top views using high-speed imaging, we show that increasing the number of spokes reduces the fraction of the droplet adhering to the surface by shortening both contact time and contact area. In addition to impact dynamics, our results reveal that the thermal properties of the surface material play a key role in determining the dominant heat transfer mechanism, ranging from finite to effectively infinite heat exchange scenarios. A comparison between theoretical models for these two regimes and experimental observations highlights how thermal conductivity influences droplet freezing behavior. Moreover, heat transfer between the droplet and the surface, estimated through contact area measurements, decreases significantly as the number of spokes increases. These findings provide mechanistic insights into how both the macrotexture design and thermal properties of nonwettable surfaces can be optimized to mitigate ice accretion by modulating contact time, interfacial area, and freezing dynamics.
Surface Potential and Surface Dipole Moment of Water and Polar-Quadrupolar Liquids.
Slavchov RI, Peychev B, Dimitrova IM
Langmuir · 2026 Jun · PMID 42376756 · Publisher ↗
Nearby interfaces, polar-quadrupolar molecules are orientated by image forces. This produces a macroscopic normal dipole moment and is the reason for the surface potential of liquids like water. The theory of the effect...
Nearby interfaces, polar-quadrupolar molecules are orientated by image forces. This produces a macroscopic normal dipole moment and is the reason for the surface potential of liquids like water. The theory of the effect requires higher-order multipole expansion of both the image interactions and the macroscopic equations of electrostatics. The quadrupolar Coulomb law predicts the formation of a dipolar double layer (DDL) at the surface, with an adsorbed layer of dipoles orientated by image forces and oppositely polarized diffuse layer formed as a response to the field of the adsorbed dipoles. We relate the surface dipolar potential to the molecular properties (dipole and quadrupole moments and molecular polarizability), the medium properties (dielectric permittivity and macroscopic quadrupolarizability), and structural characteristics of the surface layer (distance between equimolecular and dielectric surfaces, thickness of the adsorbed layer, and cavity size). The thickness of the DDL is set by the quadrupolar length of the fluid, a quantity analogous to the Debye length. Molecules on the gas-phase side of the Gibbs equimolecular surface have a large contribution to the adsorbed dipole, especially for water. The surface layer is thick enough to produce a diffuse dipole layer also on the gas-phase side of the surface, i.e., three layers of dipoles exist, in agreement with recent simulations data. The calculated unperturbed surface polarization of the adsorbed layer for water agrees with estimates from point of zero dipole of alcohol monolayers. The calculated surface potential of water (between -15 and -85 mV, depending on the assumptions; oxygen toward the gas phase) agrees with existing experimental estimates.
Particle Size-Driven Transition from Multilayer Aggregates to Ordered Monolayers at Gas Marble Interfaces.
Yasui T, Nishikawa A, Noguchi S … +6 more , Mitamura K, Martín-González J, Vogel N, Hirai T, Nakamura Y, Fujii S
Langmuir · 2026 Jun · PMID 42374980 · Publisher ↗
Gas marbles (GMs) are a family of particle-stabilized soft dispersed systems with a soap bubble-like air-in-water-in-air structure. Here, we investigate the effect of the stabilizing particle size on the resulting struct...
Gas marbles (GMs) are a family of particle-stabilized soft dispersed systems with a soap bubble-like air-in-water-in-air structure. Here, we investigate the effect of the stabilizing particle size on the resulting structure and properties of GMs. We synthesize a series of polystyrene particles with diameters between 2 and 1050 μm by dispersion polymerization and seeded dispersion polymerization. We surface-modify these particles with a poly[2-(diethylamino)ethyl methacrylate] polymeric steric stabilizer to enable interfacial adsorption to the air/water interface. This set of particles enables us to form GMs and isolate the effect of particle size on the GM formation and stabilization efficiency. We find that particles with sizes ≥80 μm adsorb as a particle monolayer to the surface of the GM, while smaller particles adsorb as ill-defined, multilayered aggregates. These results indicate that the force balance between particle-particle interaction and gravity is an important parameter to control the surface structure of the GMs. Furthermore, the degree of hexagonal ordering increases monotonically with particle size, reflecting enhanced packing regularity for larger particles. The assembly structure and size of the particles also correlate with the mechanical integrity of the GMs against fall impact. The mechanical resistance is governed by the gap between the inner liquid of the GM and the supporting substrate, as well as by the associated potential energy, both of which depend on particle size. In summary, our study systematically explores structure-property-performance relationships connecting the stabilizing particle size with the interfacial structure and the resultant mechanical stability of the macroscopic GM.
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