1
|
Kanygin Y, Nesterova I, Lomovitskiy P, Khlyupin A. Variation-Free Approach for Density Functional Theory: Data-Driven Stochastic Optimization. Ind Eng Chem Res 2022. [DOI: 10.1021/acs.iecr.2c00547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yuriy Kanygin
- Moscow Institute of Physics and Technology, Dolgoprudny, Russia, 141700
| | - Irina Nesterova
- Moscow Institute of Physics and Technology, Dolgoprudny, Russia, 141700
| | - Pavel Lomovitskiy
- Moscow Institute of Physics and Technology, Dolgoprudny, Russia, 141700
| | - Aleksey Khlyupin
- Moscow Institute of Physics and Technology, Dolgoprudny, Russia, 141700
| |
Collapse
|
2
|
Olarte-Plata JD, Brekke-Svaland G, Bresme F. The influence of surface roughness on the adhesive interactions and phase behavior of suspensions of calcite nanoparticles. NANOSCALE 2020; 12:11165-11173. [PMID: 32405631 DOI: 10.1039/d0nr00834f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We investigate the impact of nanoparticle roughness on the phase behaviour of suspensions in models of calcium carbonate nanoparticles. We use a Derjaguin approach that incorporates roughness effects and interactions between the nanoparticles modelled with a combination of DLVO forces and hydration forces, derived using experimental data and atomistic molecular dynamics simulations, respectively. Roughness effects, such as atomic steps or terraces appearing in mineral surfaces result in very different effective inter-nanoparticle potentials. Using stochastic Langevin Dynamics computer simulations and the effective interparticle interactions we demonstrate that relatively small changes in the roughness of the particles modify significantly the stability of the suspensions. We propose that the sensitivity of the phase behavior to the roughness is connected to the short length scale of the adhesive attraction arising from the ordering of water layers confined between calcite surfaces. Particles with smooth surfaces feature strong adhesive forces, and form gel fractal structures, while small surface roughness, of the order of atomic steps in mineral faces, stabilize the suspension. We believe that our work helps to rationalize the contrasting experimental results that have been obtained recently using nanoparticles or extended surfaces, which provide support for the existence of adhesive or repulsive interactions, respectively. We further use our model to analyze the synergistic effects of roughness, pH and ion concentration on the phase behavior of suspensions, connecting with recent experiments using calcium carbonate nanoparticles.
Collapse
Affiliation(s)
- Juan D Olarte-Plata
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, White City Campus, 80 Wood Lane, London W12 0BZ, UK.
| | - Gøran Brekke-Svaland
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, White City Campus, 80 Wood Lane, London W12 0BZ, UK.
| | - Fernando Bresme
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, White City Campus, 80 Wood Lane, London W12 0BZ, UK.
| |
Collapse
|
3
|
Reyes I, Palacio MM, Yarce CJ, Oñate-Garzón J, Salamanca CH. Relationship between the Ionization Degree and the Inter-Polymeric Aggregation of the Poly(maleic acid- alt-octadecene) Salts Regarding Time. Polymers (Basel) 2020; 12:polym12051036. [PMID: 32370174 PMCID: PMC7284458 DOI: 10.3390/polym12051036] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 04/17/2020] [Accepted: 04/22/2020] [Indexed: 11/23/2022] Open
Abstract
Alternating amphiphilic copolymers are macromolecular systems with a polarity duality in their structure, since they are generally formed by alternating segments corresponding to a potential electrolyte group and an alkyl (aliphatic or aromatic) group. These systems, depending on the ionization degree, as well as the time, may form different types of intra and interpolymeric aggregates in aqueous media. Therefore, this study, which in fact is the continuation of a previously reported work, is focused on establishing how the ionization degree of the sodium and potassium salts of the poly(maleic acid-alt-octadecene) affect zeta potential, pH, electrical conductivity, particle size, polydispersity index, and surface tension over time. The results showed that polymeric salts with a high ionization degree in aqueous media formed homogeneous systems with bimodal sizes and high zeta potential values, which tended to quickly become less negative, lowering the pH and slightly increasing the electrical conductivity; while systems with low ionization degree lead to the opposite, forming heterodispersed systems with several populations of particle sizes, high polydispersity, low zeta potential values, neutral and invariable pH values, and high electrical conductivity values. Consequently, these results suggest that the values of particle size, polydispersity index, zeta potential, pH, and electrical conductivity change regarding the polymeric ionization degree, as well as the time. Therefore, such variables should be considered and controlled when working with this kind of polymeric materials.
Collapse
Affiliation(s)
- Isabella Reyes
- Laboratorio de Diseño y Formulación de Productos Químicos y Derivados, Departamento de Ciencias Farmacéuticas, Facultad de Ciencias Naturales, Universidad ICESI, Calle 18 No. 122-135, Cali 760035, Colombia; (I.R.); (M.M.P.); (C.J.Y.)
| | - Maria M. Palacio
- Laboratorio de Diseño y Formulación de Productos Químicos y Derivados, Departamento de Ciencias Farmacéuticas, Facultad de Ciencias Naturales, Universidad ICESI, Calle 18 No. 122-135, Cali 760035, Colombia; (I.R.); (M.M.P.); (C.J.Y.)
| | - Cristhian J. Yarce
- Laboratorio de Diseño y Formulación de Productos Químicos y Derivados, Departamento de Ciencias Farmacéuticas, Facultad de Ciencias Naturales, Universidad ICESI, Calle 18 No. 122-135, Cali 760035, Colombia; (I.R.); (M.M.P.); (C.J.Y.)
| | - Jose Oñate-Garzón
- Grupo de Investigación en Química y Biotecnología (QUIBIO), Facultad de Ciencias Básicas, Universidad Santiago de Cali, calle 5 No. 62-00, Cali 760035, Colombia;
| | - Constain H. Salamanca
- Laboratorio de Diseño y Formulación de Productos Químicos y Derivados, Departamento de Ciencias Farmacéuticas, Facultad de Ciencias Naturales, Universidad ICESI, Calle 18 No. 122-135, Cali 760035, Colombia; (I.R.); (M.M.P.); (C.J.Y.)
- Correspondence:
| |
Collapse
|
4
|
Sauer E, Gross J. Prediction of Adsorption Isotherms and Selectivities: Comparison between Classical Density Functional Theory Based on the Perturbed-Chain Statistical Associating Fluid Theory Equation of State and Ideal Adsorbed Solution Theory. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:11690-11701. [PMID: 31403314 DOI: 10.1021/acs.langmuir.9b02378] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
This study gives an assessment of the predictive capability of classical density functional theory (DFT) for adsorption processes of pure substances and mixtures of spherical and nonspherical molecular species. A Helmholtz energy functional based on the perturbed-chain statistical associating fluid theory (PC-SAFT) is applied to calculate isotherms and selectivities of multicomponent adsorption. In order to unambiguously assess the accuracy of the DFT model, we conduct molecular simulations. Monte Carlo (MC) simulations are performed in the grand canonical ensemble using the transition matrix. Two types of systems are studied: a model system, where fluid-fluid and solid-fluid interactions are defined as (single-site) Lennard-Jones interactions, and a more realistic methane-n-butane mixture in a graphite-like pore. Differences between a slit-shaped and a cylindrical pore geometry are examined for the model system. Adsorption isotherms and selectivities obtained from DFT calculations and MC simulations are found in very good agreement, particularly at high pressures. Capillary condensation observed along adsorption isotherms containing n-butane was accurately predicted, both, in equilibrium pressure and in density-increase. Comparisons with results from the ideal adsorbed solution theory are presented, confirming powerful predictions of the DFT approach.
Collapse
Affiliation(s)
- Elmar Sauer
- Institute of Thermodynamics and Thermal Process Engineering , University of Stuttgart , Pfaffenwaldring 9 , 70569 Stuttgart , Germany
| | - Joachim Gross
- Institute of Thermodynamics and Thermal Process Engineering , University of Stuttgart , Pfaffenwaldring 9 , 70569 Stuttgart , Germany
| |
Collapse
|
5
|
Anomalous Interfacial Structuring of a Non-Halogenated Ionic Liquid: Effect of Substrate and Temperature. COLLOIDS AND INTERFACES 2018. [DOI: 10.3390/colloids2040060] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
We investigate the interfacial properties of the non-halogenated ionic liquid (IL), trihexyl(tetradecyl)phosphonium bis(mandelato)borate, [P6,6,6,14][BMB], in proximity to solid surfaces, by means of surface force measurement. The system consists of sharp atomic force microscopy (AFM) tips interacting with solid surfaces of mica, silica, and gold. We find that the force response has a monotonic form, from which a characteristic steric decay length can be extracted. The decay length is comparable with the size of the ions, suggesting that a layer is formed on the surface, but that it is diffuse. The long alkyl chains of the cation, the large size of the anion, as well as crowding of the cations at the surface of negatively charged mica, are all factors which are likely to oppose the interfacial stratification which has, hitherto, been considered a characteristic of ionic liquids. The variation in the decay length also reveals differences in the layer composition at different surfaces, which can be related to their surface charge. This, in turn, allows the conclusion that silica has a low surface charge in this aprotic ionic liquid. Furthermore, the effect of temperature has been investigated. Elevating the temperature to 40 °C causes negligible changes in the interaction. At 80 °C and 120 °C, we observe a layering artefact which precludes further analysis, and we present the underlying instrumental origin of this rather universal artefact.
Collapse
|
6
|
Goodwin ZA, Feng G, Kornyshev AA. Mean-Field Theory of Electrical Double Layer In Ionic Liquids with Account of Short-Range Correlations. Electrochim Acta 2017. [DOI: 10.1016/j.electacta.2016.12.092] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
7
|
|
8
|
Sheehan A, Jurado LA, Ramakrishna SN, Arcifa A, Rossi A, Spencer ND, Espinosa-Marzal RM. Layering of ionic liquids on rough surfaces. NANOSCALE 2016; 8:4094-4106. [PMID: 26821595 DOI: 10.1039/c5nr07805a] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Understanding the behavior of ionic liquids (ILs) either confined between rough surfaces or in rough nanoscale pores is of great relevance to extend studies performed on ideally flat surfaces to real applications. In this work we have performed an extensive investigation of the structural forces between two surfaces with well-defined roughness (<9 nm RMS) in 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide by atomic force microscopy. Statistical studies of the measured layer thicknesses, layering force, and layering frequency reveal the ordered structure of the rough IL-solid interface. Our work shows that the equilibrium structure of the interfacial IL strongly depends on the topography of the contact.
Collapse
Affiliation(s)
- Alexis Sheehan
- University of Illinois at Urbana-Champaign, Urbana 61801, Illinois, USA.
| | - L Andres Jurado
- University of Illinois at Urbana-Champaign, Urbana 61801, Illinois, USA.
| | | | | | - Antonella Rossi
- ETH Zurich, 8093 Zurich, Switzerland and Università degli Studi di Cagliari, 09042, Italy
| | | | | |
Collapse
|
9
|
Balzer C, Braxmeier S, Neimark AV, Reichenauer G. Deformation of Microporous Carbon during Adsorption of Nitrogen, Argon, Carbon Dioxide, and Water Studied by in Situ Dilatometry. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:12512-12519. [PMID: 26506409 DOI: 10.1021/acs.langmuir.5b03184] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Adsorption-induced deformation of a monolithic, synthetic carbon of clearly distinguishable micro- and mesoporosity was analyzed by in situ dilatometry with N2 (77 K), Ar (77 K), CO2 (273 K), and H2O (298 K). A characteristic nonmonotonic shape of the strain isotherm showing contraction of the sample at initial micropore adsorption followed by expansion toward completion of micropore filling was found for all adsorbates. However, the extent of contraction and expansion varied significantly with the adsorbate type. The deformation differences observed were compared with the density ratio of the adsorbates within the micropores and the respective unconfined fluids. In particular, CO2 caused the least contraction of the sample, while in parallel adsorbed CO2 molecules were predicted to be considerably compacted inside carbon micropores compared to bulk liquid CO2. On the contrary, the packing of H2O molecules within carbon micropores is less dense than in the bulk liquid and adsorption of H2O produced the most pronounced contraction. N2 and Ar, both exhibiting essentially the same densities in adsorbed and bulk liquid phase, induced very similar deformation of the sample. These findings support theoretical predictions, which correlate adsorption-induced deformation and packing of molecules adsorbed in micropores. Additionally for the first time, we demonstrated with the N2 strain isotherm the existence of two nonmonotonic stages of subsequent contraction and expansion in the regions of micropore and mesopore filling. This characteristic behavior is expected for any micro- and mesoporous material.
Collapse
Affiliation(s)
- Christian Balzer
- Bavarian Center for Applied Energy Research, Am Galgenberg 87, 97074 Wuerzburg, Germany
| | - Stephan Braxmeier
- Bavarian Center for Applied Energy Research, Am Galgenberg 87, 97074 Wuerzburg, Germany
| | - Alexander V Neimark
- Department of Chemical and Biochemical Engineering, Rutgers, The State University of New Jersey , 98 Brett Road, Piscataway, New Jersey 08854, United States
| | - Gudrun Reichenauer
- Bavarian Center for Applied Energy Research, Am Galgenberg 87, 97074 Wuerzburg, Germany
| |
Collapse
|
10
|
Krott LB, Bordin JR, Barraz NM, Barbosa MC. Effects of confinement on anomalies and phase transitions of core-softened fluids. J Chem Phys 2015; 142:134502. [PMID: 25854248 DOI: 10.1063/1.4916563] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Leandro B. Krott
- Instituto de Física, Universidade Federal do Rio Grande do Sul, Caixa Postal 15051, CEP 91501-970, Porto Alegre, RS, Brazil
| | - José Rafael Bordin
- Campus Caçapava do Sul, Universidade Federal do Pampa, Av. Pedro Anunciação, s/n, CEP 96570-000, Caçapava do Sul, RS, Brazil
| | - Ney M. Barraz
- Campus Cerro Largo, Universidade Federal da Fronteira Sul, Av. Jacob Reinaldo Haupenthal, 1580. CEP 97900-000, Cerro Largo, RS, Brazil
| | - Marcia C. Barbosa
- Instituto de Física, Universidade Federal do Rio Grande do Sul, Caixa Postal 15051, CEP 91501-970, Porto Alegre, RS, Brazil
| |
Collapse
|
11
|
Ordibeheshti Z, Aavazpour A, Sadeghi E, Hekmatzadeh S, Firouzi Z. Solvation force in hard ellipsoid fluids with HNW interaction. Mol Phys 2014. [DOI: 10.1080/00268976.2014.882520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
12
|
Patrykiejew A, Sokołowski S, Sokołowska Z, Ilnytskyi J. Fluid of Janus molecules between two walls: The solvation force. J Chem Phys 2013; 139:224711. [DOI: 10.1063/1.4840715] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
|
13
|
Landers J, Gor GY, Neimark AV. Density functional theory methods for characterization of porous materials. Colloids Surf A Physicochem Eng Asp 2013. [DOI: 10.1016/j.colsurfa.2013.01.007] [Citation(s) in RCA: 768] [Impact Index Per Article: 69.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
14
|
Jeromenok J, Weber J. Restricted access: on the nature of adsorption/desorption hysteresis in amorphous, microporous polymeric materials. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:12982-12989. [PMID: 24079886 DOI: 10.1021/la402630s] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The phenomenon of low-pressure adsorption/desorption hysteresis, which is commonly observed in microporous polymers, is investigated by detailed gas adsorption studies. Diffusional limitations by pore blocking effects, which arise as a consequence of the micropore morphology and connectivity, are discussed as the origin of the hysteresis rather than swelling effects, which have been suggested previously. Micropores with narrow openings, which cannot be filled easily, are expected to be present next to open pores. Those pores are termed restricted-access pores and are only filled in the course of the adsorption process as a consequence of the increasing solvation pressure exhibited from already filled micropores. As a consequence of the results presented here, it is suggested to use the desorption branch in addition to the adsorption branch for the extraction of the porosity characteristics, such as specific surface area, pore volume, and pore size distribution. The magnitude of the low-pressure hysteresis might hence give an idea of the micropore connectivity, which is important information for potential applications.
Collapse
Affiliation(s)
- Jekaterina Jeromenok
- Department of Colloid Chemistry, Max Planck Institute of Colloids and Interfaces , Science Park Golm, D-14424 Potsdam, Germany
| | | |
Collapse
|
15
|
Li S, Han KS, Feng G, Hagaman EW, Vlcek L, Cummings PT. Dynamic and structural properties of room-temperature ionic liquids near silica and carbon surfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:9744-9749. [PMID: 23845079 DOI: 10.1021/la401172z] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The dynamic and structural properties of a room-temperature ionic liquid (RTIL) 1-butyl-3-methyl-imidazolium(trifluoromethanesulfonimide) ([C4mim][Tf2N]) confined in silica and carbon mesopores were investigated by molecular dynamics (MD) simulations and nuclear magnetic resonance (NMR) experiments. The complex interfacial microstructures of confined [C4mim][Tf2N] are attributed to the distinctive surface features of the silica mesopore. The temperature-dependent diffusion coefficients of [C4mim][Tf2N] confined in the silica or carbon mesopore exhibit divergent behavior. The loading fraction (f = 1.0, 0.5, and 0.25) has a large effect on the magnitude of the diffusion coefficient in the silica pore and displays weaker temperature dependence as the loading fraction decreases. The diffusion coefficients of mesoporous carbon-confined [C4mim][Tf2N] are relatively insensitive to the loading faction and exhibit a temperature dependence that is similar to the bulk dependence at all loading levels. Such phenomena can be attributed to the unique surface heterogeneity, dissimilar interfacial microstructures, and interaction potential profile of RTILs near silica and carbon walls.
Collapse
Affiliation(s)
- Song Li
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee 37235, United States
| | | | | | | | | | | |
Collapse
|