Langmuir最新文献

{"title":"Interaction of Poly(acrylic acid) Brushes with Multivalent Cations: An In Situ Study.","authors":"Léo Dagand,Birgit Urban,Qiong Li,Ilka M Hermes,Eva Bittrich,Petra Uhlmann,Martin Müller,Alexander S Münch","doi":"10.1021/acs.langmuir.5c01378","DOIUrl":"https://doi.org/10.1021/acs.langmuir.5c01378","url":null,"abstract":"Weak polyelectrolyte brushes represent a versatile class of responsive surface coatings. The adjustment of their charges by modifying the pH value and the salt content of the surrounding solution has a considerable effect on the elongation of the brush, the interaction between the chains, and the degree of swelling. Recent studies have extensively demonstrated the impact of singly charged cations through theoretical and experimental means. Analyses of the interaction between polyacids and multicharged cations remain underrepresented. Therefore, the influence of multivalent cations (Ca2+ and Ce3+) on the swelling behavior of poly(acrylic acid) (PAA) brushes is investigated as a function of salt concentration and pH. Swelling measurements show a behavior that differs significantly from the well-known case of monovalent cations. To elucidate this anomalous behavior, this study employs a combination of in situ spectroscopic ellipsometry, atomic force microscopy (AFM), and attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). The investigations reveal a highly intricate interaction behavior, which can be ascribed to the multivalency of the cations utilized. The FTIR measurements indicate the impact of the cations on the pKa value of the brush and the dissociation behavior. This study provides insights into the charging properties of PAA brushes, highlighting the decisive additional influence of the valency of the cations in combination with their concentration. Multivalent ions have been observed to substitute for the protons of the carboxyl groups through an entropically driven process, resulting in degrees of dissociation, α > 0.5, even at a pH of 3, where PAA brushes are expected to be fully undissociated. This phenomenon leads to an increased degree of swelling at very low salt concentrations and a reduction at increasing ionic strength. Evidence was found for different types of ion/carboxylate coordination, with bridging coordination between the carboxyl groups of PAA and the cations.","PeriodicalId":50,"journal":{"name":"Langmuir","volume":"3 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144145958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gas-Template Synthesis of Ultrathin Porous Carbon Nitrides for Photocatalytic Redox Reactions.","authors":"Guan-Lin Yin,Xin-Yu Yang,Yi-Zhou Zhu,Xue-Qing Ma,Jian-Yu Zheng","doi":"10.1021/acs.langmuir.5c01357","DOIUrl":"https://doi.org/10.1021/acs.langmuir.5c01357","url":null,"abstract":"Graphitic carbon nitride (g-C3N4) has emerged as a promising metal-free photocatalyst but is plagued by its low activity owing to a high electron-hole recombination rate and small specific surface area. A specialized gas-template method was successfully employed to synthesize an ultrathin porous carbon nitride (UPCN) photocatalyst containing nitrogen vacancies. This thermally induced exfoliation and polycondensation approach can be modulated using different gas templates. Compared with bulk g-C3N4, UPCNs feature an optimized ultrathin structure, larger surface area, weaker fluorescence intensity, lower impedance, and higher photocurrent response. These properties contribute to more exposed active sites, shorter diffusion paths for both ions and electrons, and improved carrier separation. Consequently, UPCNs exhibit considerably enhanced photocatalytic performance in both the hydrogen evolution reaction (HER) and the photooxidation of 2,6-dimethyl-1,4-dihydro-3,5-pyridinedicarboxylic ester (1,4-DHP) under visible light. Among UPCNs, TPA-UPCN (tetrapropylammonium chloride as the gas template) exhibits the highest photocatalytic activity, surpassing NH4Cl-templated carbon nitrides (2747 vs 2092 μmol·g-1·h-1) in HER. Moreover, TPA-UPCN achieves unprecedented photocatalytic oxidation efficiency for 1,4-DHP. This study provides a new approach for the preparation of UPCN materials with enhanced photocatalytic performance.","PeriodicalId":50,"journal":{"name":"Langmuir","volume":"82 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144136753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measurement and Enhancement of Coalescence-Induced Droplet Jumping in the V-Shaped Superhydrophobic Trench with a Curved Ridge.","authors":"Lingkun Han,Chuntian Liu,Shiyu Zhang,Haoyu Li,Meirong Zhao,Yinguo Huang,Yelong Zheng","doi":"10.1021/acs.langmuir.5c00903","DOIUrl":"https://doi.org/10.1021/acs.langmuir.5c00903","url":null,"abstract":"Coalescence-induced droplet jumping demonstrates significant potential for diverse applications. However, current studies on enhancing and regulating droplet jumping largely focus on specific droplet locations and enhancement structures, significantly restricting their broader applications. This study introduces a V-shaped superhydrophobic trench with a curved ridge to enhance and control droplet coalescence jumping and directional transfer. Experimentally, a dimensionless jumping velocity (Vj* ≈ 0.69) and energy conversion efficiency (η ≈ 42.13%) were achieved, representing about 111.63% improvement in energy conversion efficiency compared to the V-shaped trench and an 879.77% increase relative to planar superhydrophobic surfaces, with a jumping angle of 66°. Numerical simulations and experiments revealed that the curved ridge enhances droplet coalescence jumping velocity and enables directional control by redirecting velocity vectors and minimizing viscous loss during coalescence. Additionally, the effects of ridge length, height, width, and opening angle on droplet coalescence jumping were analyzed via numerical simulations, offering theoretical support and technical guidance for practical applications. The coalescence jumping of droplets with unequal sizes on curved ridge structures was also studied, demonstrating that droplets with radius ratios below 0.66 can bounce off trench surfaces, confirming the structure's general applicability. This study further proposes a droplet velocity measurement method integrating target detection and trajectory fitting, achieving efficient and precise droplet velocity determination.","PeriodicalId":50,"journal":{"name":"Langmuir","volume":"63 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144136820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on the Fabrication and Performance of Mo-WO3//Co3O4-NiO Energy Storage Devices.","authors":"LiuMenghan Zheng,JiKai Yang,GuanXu Liu,JinYing Fang,GuoZheng Wang","doi":"10.1021/acs.langmuir.5c01525","DOIUrl":"https://doi.org/10.1021/acs.langmuir.5c01525","url":null,"abstract":"Lithium-ion batteries are widely used in energy storage applications. In this work, Mo-doped WO3 (Mo-WO3) thin films were prepared by a hydrothermal method, and their electrochemical storage properties were studied. Among them, the 2%Mo-WO3 thin film showed the best storage performance. Meanwhile, Co3O4-NiO codeposited thin films were prepared by electrodeposition method, and their electrochemical storage properties were also studied. The 2%Co3O4-NiO thin film showed the best storage performance. A Mo-WO3//Co3O4-NiO electrochemical storage device was constructed with the Mo-WO3 thin film as the cathode and the Co3O4-NiO thin film as the anode. This work shows that this device has an obviously improved areal capacitance (111.5 mF/cm2) and has 88% capacity retention after 500 charge and discharge cycles.","PeriodicalId":50,"journal":{"name":"Langmuir","volume":"58 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144136824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effective Separation of Acetylene/Ethylene by the Mesoporous MIL-100(Cr) MOF","authors":"Paulo G. M. Mileo, Ji Woong Yoon, Kyung Ho Cho, Ji Sun Lee, U-Hwang Lee, Guillaume Maurin, Jong-San Chang","doi":"10.1021/acs.langmuir.5c00171","DOIUrl":"https://doi.org/10.1021/acs.langmuir.5c00171","url":null,"abstract":"Acetylene plays a key role in diverse commercial chemicals and high-quality fuel applications, yet its storage poses significant challenges due to its explosive nature. In-situ plasma-assisted CH₄ coupling conversion presents a promising alternative for the safe production of C₂ chemicals, including acetylene, assuming that efficient downstream separation processes are feasible. This study focuses on the adsorptive separation of acetylene from ethylene to achieve high-purity acetylene with the use of mesoporous metal–organic frameworks (MOFs) as effective selective adsorbents. Herein, we systematically investigate the acetylene/ethylene separation performance of a series of MIL-100 (M = Al, Fe, V, Cr) MOFs. Single-component sorption data first evidenced that MIL-100(Cr) shows the highest affinity to acetylene, supported by Operando Infrared spectroscopy and Density Functional Theory calculations. These analysis revealed the crucial role played by the Cr³⁺ coordinatively unsaturated sites and the counter-anions (OH^–/F^–) bound to 1 of the 3 Cr³⁺ atoms of the oxo-trimer. Grand Canonical Monte Carlo simulations further elucidated the microscopic adsorption mechanisms for each single-component and equimolar binary acetylene/ethylene mixtures. Breakthrough experiments demonstrated that MIL-100(Cr) achieves selectivity ranging from 5 to 23, suggesting its potential for dual high-purity acetylene and ethylene production. Vacuum Pressure Swing Adsorption (VPSA) cycle tests indicated that MIL-100(Cr) achieves high acetylene recovery and moderate purity without a rinse step, while an acetylene rinse step enhances purity for fine chemical raw materials. Overall, this study paves the way toward the promotion of MIL-100(Cr) for future large-scale industrial applications in acetylene harvesting and purification.","PeriodicalId":50,"journal":{"name":"Langmuir","volume":"46 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144133529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Self-Driven Fluid Imbibition of Salt Solutions into Mesoporous Films","authors":"Laura Czerwenka, Annette Andrieu-Brunsen","doi":"10.1021/acs.langmuir.5c00650","DOIUrl":"https://doi.org/10.1021/acs.langmuir.5c00650","url":null,"abstract":"Fluid water imbibition into nanoscale porous materials is important in nature and technology and has been shown to follow the Lucas–Washburn behavior. Looking at drop imbibition into nanoscale porous films, the imbibition reaches a steady state governed by capillary imbibition and evaporation, which is reflected in a constant imbibition length. This imbibition length in a steady state depends on the porous structure as well as on the material’s wettability and the fluid evaporation rate, for example. As the presence of salts affects these parameters, the imbibition length is expected to be influenced by the solutes present in the drop. Here, we show the influence of salt presence, salt concentration, and ion type on the fluid imbibition of an aqueous salt solution into mesoporous silica films. We observe that salts affect the Lucas–Washburn imbibition occurring directly after drop positioning on mesoporous films. Interestingly, the presence of salts also causes a continuous increase of the characteristic imbibition length at longer time scales, preventing the formation of a steady state after the initial Lucas–Washburn-like imbibition. We identified a self-amplified fluid pumping mechanism using mesoporous silica films. We attribute this continuous fluid pumping and, thus, the continuous increase of the imbibition length to the increasing osmotic pressure within mesoporous materials upon constant fluid flow and fluid evaporation. Understanding aqueous salt solution imbibition into mesoporous films is an important aspect, e.g., in the context of material exchange between drops through mesoporous films.","PeriodicalId":50,"journal":{"name":"Langmuir","volume":"32 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144133535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Formation and Stabilization of Bulk Nanobubbles Triggered by Ultrasonic Irradiation under Different Conditions","authors":"Nan Guan, Yao Wang, Xingya Wang, Xiaoqing Cai, Chen Hou, Jun Hu, Lijuan Zhang","doi":"10.1021/acs.langmuir.5c00327","DOIUrl":"https://doi.org/10.1021/acs.langmuir.5c00327","url":null,"abstract":"The generation and stabilization of nanobubbles (NBs) are crucial concerns, considering their great potential for applications in various fields. Nonetheless, research on the stabilization of bulk nanobubbles (BNBs) generation across various systems under ultrasonic irradiation is relatively few. For example, how dissolved gases and different conditions affect the evolution of BNBs in the acoustic field remains unclear. Therefore, this study focused on generating and stabilizing BNBs over time under various conditions including ultrasonic frequency, power, and dissolved gases in both open and closed systems. First, for a given solution, the concentration of BNBs would increase with higher ultrasonic power and lower ultrasonic frequency. Furthermore, a considerably elevated concentration of BNBs was obtained in closed systems relative to open systems, which may be attributed to a closed system providing a more stable environment for nucleation growth, thus facilitating the generation and stabilization of BNBs. More surprisingly, by changing dissolved gas saturation, we found that in gas-saturated water, the concentration of BNBs becomes higher than in the other two saturations: supersaturated and undersaturated water. A detailed study also found that the concentration of formed BNBs differs based on the positions of vessel, and more BNBs will be formed at the bottom or upper side of the vessel, indicating bubbles easily nucleate near the vessel wall and at the gas–liquid interface. This study provides essential insights into the principles of the generation and stabilization of NBs under ultrasonic fields, potentially expanding application ranges and improving the efficiency of ultrasonic irradiation.","PeriodicalId":50,"journal":{"name":"Langmuir","volume":"238 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144130341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Controlled Electrospraying of Sericin Nanoparticles for Enhancing the Functional Surface Properties of Polyester Fabrics.","authors":"Lisha Zhu,Yue Zhu,Rongxing Li,Lei Liang,Yuxin Li,Juan P Hinestroza,Wangyang Lu,Juming Yao,Wenbin Jiang","doi":"10.1021/acs.langmuir.5c01555","DOIUrl":"https://doi.org/10.1021/acs.langmuir.5c01555","url":null,"abstract":"Sericin, a hydrophilic and moisturizing natural protein, is typically discarded during silk degumming, leading to resource waste and environmental pollution. This study introduces a novel surface engineering strategy by applying electrospraying to deposit sericin nanoparticles onto polyester fabrics─marking the first use of this technique to functionalize synthetic textiles with natural biopolymers. This method enables precise control over nanoparticle size and uniform deposition, offering a sustainable and scalable approach for enhancing interfacial properties. Through Response Surface Methodology (RSM) and Box-Behnken Design (BBD), we optimized key electrospraying parameters (polymer concentration, voltage, and needle size), achieving a minimum particle diameter of 36 nm. The sericin nanoparticle coating significantly improved the surface properties of polyester fabrics: reducing the water contact angle from 140° to 88°, shortening wetting time from 26 to 11 min, and increasing moisture regain from 0.21 to 0.91%. UV protection was also enhanced, with the Ultraviolet Protection Factor (UPF) rising from 94.77 to 123.18. Importantly, the sericin coating demonstrated excellent wash durability, retaining over 85% of its UV-blocking performance after 20 cycles. This work advances surface and interface science by pioneering the use of electrospraying for biobased coatings on synthetic substrates, offering a precise, eco-friendly solution for sustainable sericin waste valorization while achieving durable and multifunctional surface modifications. Our findings contribute to the development of advanced interfacial materials and sustainable textile manufacturing.","PeriodicalId":50,"journal":{"name":"Langmuir","volume":"1 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144122272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis of Three-Dimensional β-In2S3 Nanoflowers with a Tunable Surface Area for Boosted Photocatalytic Degradation of Tetracycline and Rhodamine B.","authors":"Thi Thom Nguyen,Jaspal Singh,Van Anh Nguyen,Thi Linh Giang Hoang,Phuong Nguyen-Tri","doi":"10.1021/acs.langmuir.5c01251","DOIUrl":"https://doi.org/10.1021/acs.langmuir.5c01251","url":null,"abstract":"Three-dimensional (3D) β-In2S3 nanoflowers with a tunable surface area were successfully synthesized by a simple hydrothermal method. Their growth mechanism, observed through transmission electron microscopy (TEM) and scanning electron microscopy (SEM), revealed the formation of In2S3 flowers by the assembly of 2D In2S3 nanosheets. This unique 3D structure enhances optical absorption and tailors the band gap, as evidenced by UV-vis DRS and photoluminescence (PL) analyses. XRD and Raman spectroscopy confirm the β-phase of the synthesized In2S3 nanoflowers. The tunable surface area of the samples was confirmed by Brunauer-Emmett-Teller (BET) analysis. As a result, the prepared material exhibits an enhanced degradation efficiency to tetracycline (TC) and Rhodamine B (RhB), reaching up to 85.4 and 99.4% after 240 and 60 min under irradiation by low-power household LED (60 W), respectively, which has not been reported yet. Radical trapping experiments indicated that O2•- was the primary reactive species responsible for the photocatalytic degradation of RhB and TC molecules in the β-In2S3 system. The excellent photocatalytic properties and high structural stability of β-In2S3 make it a promising material for degrading antibiotics and persistent textile pollutants.","PeriodicalId":50,"journal":{"name":"Langmuir","volume":"43 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144122345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Construction of Low-Energy Prepared Highly Stable Surfactant Emulsion by Optimizing Composition Configuration","authors":"Fang Wang, Cheng Ma, Jianbin Huang","doi":"10.1021/acs.langmuir.5c01936","DOIUrl":"https://doi.org/10.1021/acs.langmuir.5c01936","url":null,"abstract":"Emulsion systems that are independent of preparation conditions and time are ideal models for fundamental emulsion research. However, special strategies are required to form these emulsions, particularly with commonly used oils and emulsifiers that have proven to be more difficult. In this study, an efficient approach to preparing a low-energy emulsion with outstanding stability is reported. This approach is derived from a comprehensive study of the component composition in the residual emulsified fractions in water-separation emulsions. The outstandingly stable emulsion exhibits a highly stacked droplet structure, which can restrict the droplet movement within the disperse medium, accompanied by a stable oil–water interface layer, which can hinder the molecular exchange between droplets and resist droplet destruction under extreme conditions, thereby preventing the demulsification caused by sedimentation, coalescence, and Ostwald ripening. These peculiarities enable the emulsion to remain stable over long periods and at elevated temperatures, even exhibiting a spontaneous tendency to recover to the emulsion after centrifugal phase splitting. This approach lends itself to generalization in the context of multiple surfactants or oil phases, thus establishing a foundation for the study of various emulsifiers and functional emulsions. Moreover, the low-energy-input preparation can reduce energy consumption in the emulsion production, aligning with the principles of green development.","PeriodicalId":50,"journal":{"name":"Langmuir","volume":"59 3 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144122513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}