1
|
Brookes SGH, Kapil V, Schran C, Michaelides A. The wetting of H2O by CO2. J Chem Phys 2024; 161:084711. [PMID: 39193944 DOI: 10.1063/5.0224230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2024] [Accepted: 07/24/2024] [Indexed: 08/29/2024] Open
Abstract
Biphasic interfaces are complex but fascinating regimes that display a number of properties distinct from those of the bulk. The CO2-H2O interface, in particular, has been the subject of a number of studies on account of its importance for the carbon life cycle as well as carbon capture and sequestration schemes. Despite this attention, there remain a number of open questions on the nature of the CO2-H2O interface, particularly concerning the interfacial tension and phase behavior of CO2 at the interface. In this paper, we seek to address these ambiguities using ab initio-quality simulations. Harnessing the benefits of machine-learned potentials and enhanced statistical sampling methods, we present an ab initio-level description of the CO2-H2O interface. Interfacial tensions are predicted from 1 to 500 bars and found to be in close agreement with experiment at pressures for which experimental data are available. Structural analyses indicate the buildup of an adsorbed, saturated CO2 film forming at a low pressure (20 bars) with properties similar to those of the bulk liquid, but preferential perpendicular alignment with respect to the interface. The CO2 monolayer buildup coincides with a reduced structuring of water molecules close to the interface. This study highlights the predictive nature of machine-learned potentials for complex macroscopic properties of biphasic interfaces, and the mechanistic insight obtained into carbon dioxide aggregation at the water interface is of high relevance for geoscience, climate research, and materials science.
Collapse
Affiliation(s)
- Samuel G H Brookes
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
- Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge CB3 0HE, United Kingdom
- Lennard-Jones Centre, University of Cambridge, Trinity Ln, Cambridge CB2 1TN, United Kingdom
| | - Venkat Kapil
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
- Lennard-Jones Centre, University of Cambridge, Trinity Ln, Cambridge CB2 1TN, United Kingdom
- Department of Physics and Astronomy, University College London, 17-19 Gordon Street, London WC1H 0AH, United Kingdom
- Thomas Young Centre and London Centre for Nanotechnology, 19 Gordon Street, London WC1H 0AH, United Kingdom
| | - Christoph Schran
- Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge CB3 0HE, United Kingdom
- Lennard-Jones Centre, University of Cambridge, Trinity Ln, Cambridge CB2 1TN, United Kingdom
| | - Angelos Michaelides
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
- Lennard-Jones Centre, University of Cambridge, Trinity Ln, Cambridge CB2 1TN, United Kingdom
| |
Collapse
|
2
|
Takaba K, Friedman AJ, Cavender CE, Behara PK, Pulido I, Henry MM, MacDermott-Opeskin H, Iacovella CR, Nagle AM, Payne AM, Shirts MR, Mobley DL, Chodera JD, Wang Y. Machine-learned molecular mechanics force fields from large-scale quantum chemical data. Chem Sci 2024; 15:12861-12878. [PMID: 39148808 PMCID: PMC11322960 DOI: 10.1039/d4sc00690a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Accepted: 06/17/2024] [Indexed: 08/17/2024] Open
Abstract
The development of reliable and extensible molecular mechanics (MM) force fields-fast, empirical models characterizing the potential energy surface of molecular systems-is indispensable for biomolecular simulation and computer-aided drug design. Here, we introduce a generalized and extensible machine-learned MM force field, espaloma-0.3, and an end-to-end differentiable framework using graph neural networks to overcome the limitations of traditional rule-based methods. Trained in a single GPU-day to fit a large and diverse quantum chemical dataset of over 1.1 M energy and force calculations, espaloma-0.3 reproduces quantum chemical energetic properties of chemical domains highly relevant to drug discovery, including small molecules, peptides, and nucleic acids. Moreover, this force field maintains the quantum chemical energy-minimized geometries of small molecules and preserves the condensed phase properties of peptides and folded proteins, self-consistently parametrizing proteins and ligands to produce stable simulations leading to highly accurate predictions of binding free energies. This methodology demonstrates significant promise as a path forward for systematically building more accurate force fields that are easily extensible to new chemical domains of interest.
Collapse
Affiliation(s)
- Kenichiro Takaba
- Computational and Systems Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center New York NY 10065 USA
- Pharmaceuticals Research Center, Advanced Drug Discovery, Asahi Kasei Pharma Corporation Shizuoka 410-2321 Japan
| | - Anika J Friedman
- Department of Chemical and Biological Engineering, University of Colorado Boulder Boulder CO 80309 USA
| | - Chapin E Cavender
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego 9500 Gilman Drive La Jolla CA 92093 USA
| | - Pavan Kumar Behara
- Center for Neurotherapeutics, Department of Pathology and Laboratory Medicine, University of California Irvine CA 92697 USA
| | - Iván Pulido
- Computational and Systems Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center New York NY 10065 USA
| | - Michael M Henry
- Computational and Systems Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center New York NY 10065 USA
| | | | - Christopher R Iacovella
- Computational and Systems Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center New York NY 10065 USA
| | - Arnav M Nagle
- Computational and Systems Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center New York NY 10065 USA
- Department of Bioengineering, University of California, Berkeley Berkeley CA 94720 USA
| | - Alexander Matthew Payne
- Computational and Systems Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center New York NY 10065 USA
- Tri-Institutional PhD Program in Chemical Biology, Memorial Sloan Kettering Cancer Center New York 10065 USA
| | - Michael R Shirts
- Department of Chemical and Biological Engineering, University of Colorado Boulder Boulder CO 80309 USA
| | - David L Mobley
- Department of Pharmaceutical Sciences, University of California Irvine California 92697 USA
| | - John D Chodera
- Computational and Systems Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center New York NY 10065 USA
| | - Yuanqing Wang
- Simons Center for Computational Physical Chemistry and Center for Data Science, New York University New York NY 10004 USA
- Computational and Systems Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center New York NY 10065 USA
| |
Collapse
|
3
|
Nicolás-Apolinar B, Ibarra-Tandi B, López-Lemus J, Luis-Jiménez DP. Influence of molecular parameters on the representativeness of interfacial properties of simple fluids. J Chem Phys 2024; 161:054711. [PMID: 39092958 DOI: 10.1063/5.0210919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Accepted: 07/16/2024] [Indexed: 08/04/2024] Open
Abstract
New parameterizations for the Lennard-Jones 12/6 potential capable of reproducing the vapor pressure and surface tension with sufficient precision, but not the liquid-vapor equilibrium densities for the case of simple fluids that include Ar, Kr, Xe, Ne, and CH4 are presented in this work. These results are compared with those derived from the family of Mie(n, 6) potentials, which adequately reproduce the coexistence curve and the vapor pressure, leaving aside the surface tension. In addition, a detailed analysis is presented on different parameterizations and methodologies, which have been developed in recent decades to estimate the interfacial properties of interest here for simple fluids, such as argon, which is a molecule that is, in principle, "simple" to study but that clearly reveals the enormous discrepancy between the results reported in the literature throughout these years. These facts undoubtedly reveal one of the fundamental problems in the context of molecular thermodynamics of fluids: reproducing different thermodynamic properties with sufficient precision from a single set of free parameters for some interaction potential. In order to show the scope of the parameterizations presented for the Lennard-Jones model, they were successfully applied to the case of binary mixtures, which included Ar-Kr, Ar-CH4, and Xe-Kr. Finally, and with the aim of showing a possible solution to the problem posed in this research, results of the same interfacial properties above mentioned for argon and methane were presented in this work by using a set of molecular interactions, called ANC2s, whose flexibility allowed to reproduce the experimental evidence with just one parameterization. The results reported in this work were generated using molecular dynamics simulations.
Collapse
Affiliation(s)
- B Nicolás-Apolinar
- Facultad de Ciencias, Universidad Autónoma del Estado de México, CP 50200 Toluca, Mexico
| | - B Ibarra-Tandi
- Facultad de Ciencias, Universidad Autónoma del Estado de México, CP 50200 Toluca, Mexico
| | - J López-Lemus
- Facultad de Ciencias, Universidad Autónoma del Estado de México, CP 50200 Toluca, Mexico
| | - D P Luis-Jiménez
- CONACYT Research Fellow-Centro de Ingeniería y Desarrollo Industrial, CP 76130 Querétaro, Mexico
| |
Collapse
|
4
|
Al-Awad AS, Batet L, Rives R, Sedano L. Stochastic computer experiments of the thermodynamic irreversibility of bulk nanobubbles in supersaturated and weak gas-liquid solutions. J Chem Phys 2024; 161:024503. [PMID: 38984961 DOI: 10.1063/5.0204665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Accepted: 06/24/2024] [Indexed: 07/11/2024] Open
Abstract
Spontaneous gas-bubble nucleation in weak gas-liquid solutions has been a challenging topic in theory, experimentation, and computer simulations. In analogy with recent advances in crystallization and droplet formation studies, the diffusive-shielding stabilization and thermodynamic irreversibility of bulk nanobubble (bNB) mechanisms are revisited and deployed to characterize nucleation processes in a stochastic framework of computer experiments using the large-scale atomic/molecular massively parallel simulator code. Theoretical bases, assumptions, and limitations underlying the irreversibility hypothesis of bNBs, and their computational counterparts, are extensively described and illustrated. In essence, it is established that the irreversibility hypothesis can be numerically investigated by converging the system volume (due to the finiteness of interatomic forces) and the initial dissolved-gas concentration in the solution (due to the single-bNB limitation). Helium nucleation in liquid Pb17Li alloy is selected as a representative case study, where it exhibits typical characteristics of noble-gas/liquid-metal systems. The proposed framework lays down the bases on which the stability of gas-bNBs in weak and supersaturated gas-liquid solutions can be inferred and explained from a novel perspective. In essence, it stochastically marches toward a unique irreversible state along out-of-equilibrium nucleation/growth trajectories. Moreover, it does not attempt to characterize the interface or any interface-related properties, neither theoretically nor computationally. It was concluded that bNBs of a few tens of He-atoms are irreversible when dissolved-He concentrations in the weak gas-liquid solution are at least ∼50 and ∼105 mol m-3 at 600 and 1000 K (and ∼80 MPa), respectively, whereas classical molecular dynamics -estimated solubilities are at least two orders of magnitude smaller.
Collapse
Affiliation(s)
- Abdulrahman S Al-Awad
- Department of Physics, Universitat Politècnica de Catalunya-BarcelonaTech (UPC), Barcelona 08028, Spain
| | - Lluis Batet
- Department of Physics, Universitat Politècnica de Catalunya-BarcelonaTech (UPC), Barcelona 08028, Spain
| | - Ronny Rives
- Department of Physics, Universitat Politècnica de Catalunya-BarcelonaTech (UPC), Barcelona 08028, Spain
| | - Luis Sedano
- Department of Physics, Universitat Politècnica de Catalunya-BarcelonaTech (UPC), Barcelona 08028, Spain
- Instituto de Ciencia de Materiales de Barcelona (ICMAB/CSIC), Bellaterra 08193, Spain
| |
Collapse
|
5
|
Wang H, Zhang H, Zhang X, Cao T, Shi J, Fan X. Structural superlubricity at the interface of penta-BN 2. Phys Chem Chem Phys 2024; 26:18871-18880. [PMID: 38946706 DOI: 10.1039/d4cp00619d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/02/2024]
Abstract
Two-dimensional (2D) materials have been widely used as lubricants due to their weak interlayer interaction and low shear resistance for interlayer sliding. Composed entirely of five-membered rings, penta-BN2 monolayer has excellent thermal and mechanical stability, higher hardness and a negative Poisson's ratio. In this work, we investigate the frictional properties at both the commensurate and incommensurate contacting interfaces of penta-BN2 by adopting the molecular dynamics (MD) simulation method. Our calculations demonstrate robust superlubricity at the incommensurate contacting interface of penta-BN2. The ultra-low friction is explained by the potential energy surface (PES) fluctuations, interlayer binding energy and out-of-plane motion amplitude of the sliding layer. In addition, our calculations show that the anisotropy of friction at the commensurate contacting interface is more obvious compared with that at the incommensurate contacting interface. Finally, the influences of the size of the Moiré pattern, normal force, temperature and sliding velocity on the friction are examined. Our results show that 2D penta-BN2 is a promising solid lubricant, enriching the family of 2D lubrication materials.
Collapse
Affiliation(s)
- Hao Wang
- State Key Laboratory of Solidification Processing, Center for Advanced Lubrication and Seal Materials, School of Material Science and Engineering, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, China.
| | - Hanyue Zhang
- Queen Mary University of London Engineering School, Northwestern Polytechnical University, 127 YouYi Western Road, Xi'an, Shaanxi, 710072, China
| | - Xinqi Zhang
- State Key Laboratory of Solidification Processing, Center for Advanced Lubrication and Seal Materials, School of Material Science and Engineering, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, China.
| | - Tengfei Cao
- State Key Laboratory of Solidification Processing, Center for Advanced Lubrication and Seal Materials, School of Material Science and Engineering, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, China.
| | - Junqi Shi
- State Key Laboratory of Solidification Processing, Center for Advanced Lubrication and Seal Materials, School of Material Science and Engineering, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, China.
| | - Xiaoli Fan
- State Key Laboratory of Solidification Processing, Center for Advanced Lubrication and Seal Materials, School of Material Science and Engineering, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, China.
| |
Collapse
|
6
|
Wang WB, Li W, Ohta R, Kambara M. Cluster-Assisted Mesoplasma Chemical Vapor Deposition for Fast Epitaxial Growth of SiGe/Si Heterostructures: A Molecular Dynamics Simulation Study. MATERIALS (BASEL, SWITZERLAND) 2024; 17:2448. [PMID: 38793514 PMCID: PMC11123204 DOI: 10.3390/ma17102448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 05/15/2024] [Accepted: 05/16/2024] [Indexed: 05/26/2024]
Abstract
Co-condensation of mixed SiGe nanoclusters and impingement of SiGe nanoclusters on a Si substrate were applied using molecular dynamics (MD) simulation in this study to mimic the fast epitaxial growth of SiGe/Si heterostructures under mesoplasma chemical vapor deposition (CVD) conditions. The condensation dynamics and properties of the SiGe nanoclusters during the simulations were investigated first, and then the impingement of transient SiGe nanoclusters on both Si smooth and trench substrate surfaces under varying conditions was studied theoretically. The results show that the mixed nanoclusters as precursors demonstrate potential for enhancing epitaxial SiGe film growth at a high growth rate, owing to their loosely bound atomic structures and high mobility on the substrate surface. By varying cluster sizes and substrate temperatures, this study also reveals that smaller clusters and higher substrate temperatures contribute to faster structural ordering and smoother surface morphologies. Furthermore, the formed layers display a consistent SiGe composition, closely aligning with nominal values, and the cluster-assisted deposition method achieves the epitaxial bridging of heterostructures during cluster impingement, highlighting its additional distinctive characteristics. The implications of this work make it clear that the mechanism of fast alloyed epitaxial film growth by cluster-assisted mesoplasma CVD is critical for extending it as a versatile platform for synthesizing various epitaxial films.
Collapse
Affiliation(s)
- Wen-bo Wang
- School of Materials Science and Engineering, Dongguan University of Technology, Dongguan 523808, China;
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - Wenfang Li
- School of Materials Science and Engineering, Dongguan University of Technology, Dongguan 523808, China;
| | - Ryoshi Ohta
- Department of Materials Engineering, The University of Tokyo, 7-3-1, Hongo, Bunkyo, Tokyo 113-8656, Japan
| | - Makoto Kambara
- Department of Materials Engineering, The University of Tokyo, 7-3-1, Hongo, Bunkyo, Tokyo 113-8656, Japan
- Department of Materials and Manufacturing Science, Osaka University, 2-1, Yamadaoka, Suita 565-0871, Japan
| |
Collapse
|
7
|
Cai S, Yu L, Huo E, Ren Y, Liu X, Chen Y. Adsorption and Diffusion Properties of Functionalized MOFs for CO 2 Capture: A Combination of Molecular Dynamics Simulation and Density Functional Theory Calculation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:6869-6877. [PMID: 38498690 DOI: 10.1021/acs.langmuir.3c03782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/20/2024]
Abstract
The capture of carbon dioxide (CO2) from fuel gases is a significant method to solve the global warming problem. Metal-organic frameworks (MOFs) are considered to be promising porous materials and have shown great potential for CO2 adsorption and separation applications. However, the adsorption and diffusion mechanisms of CO2 in functionalized MOFs from the perspective of binding energies are still not clear. Actually, the adsorption and diffusion mechanisms can be revealed more intuitively by the binding energies of CO2 with the functionalized MOFs. In this work, a combination of molecular dynamics simulation and density functional theory calculation was performed to study CO2 adsorption and diffusion mechanisms in five different functionalized isoreticular MOFs (IRMOF-1 through -5), considering the influence of functionalized linkers on the adsorption capacity of functionalized MOFs. The results show that the CO2 uptake is determined by two elements: the binding energy and porosity of MOFs. The porosity of the MOFs plays a dominant role in IRMOF-5, resulting in the lowest level of CO2 uptake. The potential of mean force (PMF) of CO2 is strongest at the CO2/functionalized MOFs interface, which is consistent with the maximum CO2 density distribution at the interface. IRMOF-3 with the functionalized linker -NH2 shows the highest CO2 uptake due to the higher porosity and binding energy. Although IRMOF-5 with the functionalized linker -OC5H11 exhibits the lowest diffusivity of CO2 and the highest binding energy, it shows the lowest CO2 uptake. Accordingly, among the five simulated functionalized MOFs, IRMOF-3 is an excellent CO2 adsorbent and IRMOF-5 can be used to separate CO2 from other gases, which will be helpful for the designing of CO2 capture devices. This work will contribute to the design and screening of materials for CO2 adsorption and separation in practical applications.
Collapse
Affiliation(s)
- Shouyin Cai
- College of Electrical, Energy and Power Engineering, Yangzhou University, Yangzhou 225127, P.R. China
| | - Lin Yu
- Institute of Translational Medicine, Medical College, Yangzhou University, Yangzhou 225127, P.R. China
| | - Erguang Huo
- School of Physical Science and Technology, Suzhou University of Science and Technology, Suzhou 215009, P.R. China
| | - Yunxiu Ren
- College of Electrical, Energy and Power Engineering, Yangzhou University, Yangzhou 225127, P.R. China
- College of Civil Engineering and Architecture, Shandong University of Science and Technology, Qingdao 266590, P.R. China
| | - Xiangdong Liu
- College of Electrical, Energy and Power Engineering, Yangzhou University, Yangzhou 225127, P.R. China
| | - Yongping Chen
- College of Electrical, Energy and Power Engineering, Yangzhou University, Yangzhou 225127, P.R. China
- Jiangsu Key Laboratory of Micro and Nano Heat Fluid Flow Technology and Energy Application, School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, P.R. China
| |
Collapse
|
8
|
Khabibrakhmanov A, Fedorov DV, Tkatchenko A. Universal Pairwise Interatomic van der Waals Potentials Based on Quantum Drude Oscillators. J Chem Theory Comput 2023; 19:7895-7907. [PMID: 37875419 PMCID: PMC10653113 DOI: 10.1021/acs.jctc.3c00797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 09/30/2023] [Accepted: 10/05/2023] [Indexed: 10/26/2023]
Abstract
Repulsive short-range and attractive long-range van der Waals (vdW) forces play an appreciable role in the behavior of extended molecular systems. When using empirical force fields, the most popular computational methods applied to such systems, vdW forces are typically described by Lennard-Jones-like potentials, which unfortunately have a limited predictive power. Here, we present a universal parameterization of a quantum-mechanical vdW potential, which requires only two free-atom properties─the static dipole polarizability α1 and the dipole-dipole C6 dispersion coefficient. This is achieved by deriving the functional form of the potential from the quantum Drude oscillator (QDO) model, employing scaling laws for the equilibrium distance and the binding energy, and applying the microscopic law of corresponding states. The vdW-QDO potential is shown to be accurate for vdW binding energy curves, as demonstrated by comparing to the ab initio binding curves of 21 noble-gas dimers. The functional form of the vdW-QDO potential has the correct asymptotic behavior at both zero and infinite distances. In addition, it is shown that the damped vdW-QDO potential can accurately describe vdW interactions in dimers consisting of group II elements. Finally, we demonstrate the applicability of the atom-in-molecule vdW-QDO model for predicting accurate dispersion energies for molecular systems. The present work makes an important step toward constructing universal vdW potentials, which could benefit (bio)molecular computational studies.
Collapse
Affiliation(s)
- Almaz Khabibrakhmanov
- Department of Physics and Materials
Science, University of Luxembourg, L-1511 Luxembourg
City, Luxembourg
| | - Dmitry V. Fedorov
- Department of Physics and Materials
Science, University of Luxembourg, L-1511 Luxembourg
City, Luxembourg
| | - Alexandre Tkatchenko
- Department of Physics and Materials
Science, University of Luxembourg, L-1511 Luxembourg
City, Luxembourg
| |
Collapse
|
9
|
Guo L, Pan L, Li Z. Study on the Sliding Tribological Behavior of Oleic Acid-Modified MoS 2 under Boundary Lubrication. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:14562-14572. [PMID: 37807858 DOI: 10.1021/acs.langmuir.3c01791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
The effects of MoS2 and MoS2 modified by adding oleic acid (OA) on the friction properties of lithium-based grease under boundary lubrication conditions are studied by molecular dynamics (MD) simulation and experiment. A rough wall boundary lubrication MD model with peaks and grooves is established to simulate the mechanical properties and lubrication effects of three lubrication systems on rough walls for the relative shear velocity between the two solid walls of 5 m/s at 500 MPa. The stress, wear amount, friction force, normal pressure, and friction heat of the friction surface are quantitively calculated. Simultaneously, a Retc friction and wear testing machine is used to measure the friction coefficient under different concentrations of additives and different pressures. The results show that the grease added with MoS2 can reduce friction, wear, and the temperature between friction pairs. However, under high pressure and shear, MoS2 can easily agglomerate and accumulate in the pits, reducing the lubricating effect. At the same time, since OA-modified MoS2 can reduce agglomeration, the modified MoS2 is adsorbed on the metal wall surface, forming a stable lubricant film. The main contributions of this article can be found in combining MD simulation and experimentation, establishing the connection between micronano structures and macroscopic properties, exploring the mechanism of the influence of wall roughness and particle size on the friction performance of lubricating oil, and providing a theory for predicting and developing high-performance new lubricating grease.
Collapse
Affiliation(s)
- Liming Guo
- School of Mechanical Engineering and Automation, Fuzhou University, Fuzhou, Fujian 350108, China
- Fuzhou Friction and Lubrication Industry Technology Innovation Center, Fuzhou, Fujian 350108, China
| | - Ling Pan
- School of Mechanical Engineering and Automation, Fuzhou University, Fuzhou, Fujian 350108, China
- Fuzhou Friction and Lubrication Industry Technology Innovation Center, Fuzhou, Fujian 350108, China
| | - Zhi Li
- School of Mechanical Engineering and Automation, Fuzhou University, Fuzhou, Fujian 350108, China
- Fuzhou Friction and Lubrication Industry Technology Innovation Center, Fuzhou, Fujian 350108, China
| |
Collapse
|
10
|
Liu W, Wang N, Chen J, Shen A, Liang F. Desorption properties of the R600, R134a and their mixtures in several MOF structures: A molecular dynamics study. Heliyon 2023; 9:e20774. [PMID: 37842621 PMCID: PMC10568097 DOI: 10.1016/j.heliyon.2023.e20774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Revised: 08/10/2023] [Accepted: 10/05/2023] [Indexed: 10/17/2023] Open
Abstract
The efficiency of organic Rankine cycle is expected to be enhanced via using metal organic heat carriers. Thus, it is important to investigate the properties of organic working fluid in metal organic frameworks (MOFs). In this paper, molecular dynamics method was employed to study the desorption properties of R600, R134a, and their mixtures in MOF-5, IRMOF-16, and MOF-200 structures. The results show that the desorption capacity of pure working fluids are negatively correlated with their molecular size. In mixed refrigerant systems, the desorption of the working medium is competitive, and the higher the proportion of fluorine atoms in the system, the greater the desorption heat in IRMOF-16. It is noteworthy that the behavior of the desorption heat in the other two MOFs is diametrically opposed to this result. The desorption capacity is positively correlated with the average pore size, specific surface area, and porosity of the MOF. The self-diffusion coefficient of the working medium in MOF is inversely proportional to its molecular weight, but directly proportional to its molecular size and to the pore size of MOF.
Collapse
Affiliation(s)
- Wei Liu
- State Power Investment Corporation Central Research Institute (SPICRI), Beijing, 100029, China
| | - Nan Wang
- State Power Investment Corporation Central Research Institute (SPICRI), Beijing, 100029, China
| | - Jun Chen
- State Power Investment Corporation Central Research Institute (SPICRI), Beijing, 100029, China
| | - Aijing Shen
- State Power Investment Corporation Central Research Institute (SPICRI), Beijing, 100029, China
| | - Fu Liang
- Chongqing University, School of Graduate, Chongqing, 400030, China
| |
Collapse
|
11
|
Mohammadi E, Joshi SY, Deshmukh SA. Development, Validation, and Applications of Nonbonded Interaction Parameters between Coarse-Grained Amino Acid and Water Models. Biomacromolecules 2023; 24:4078-4092. [PMID: 37603467 DOI: 10.1021/acs.biomac.3c00441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/23/2023]
Abstract
Interactions between amino acids and water play an important role in determining the stability and folding/unfolding, in aqueous solution, of many biological macromolecules, which affects their function. Thus, understanding the molecular-level interactions between water and amino acids is crucial to tune their function in aqueous solutions. Herein, we have developed nonbonded interaction parameters between the coarse-grained (CG) models of 20 amino acids and the one-site CG water model. The nonbonded parameters, represented using the 12-6 Lennard Jones (LJ) potential form, have been optimized using an artificial neural network (ANN)-assisted particle swarm optimization (PSO) (ANN-assisted PSO) method. All-atom (AA) molecular dynamics (MD) simulations of dipeptides in TIP3P water molecules were performed to calculate the Gibbs hydration free energies. The nonbonded force-field (FF) parameters between CG amino acids and the one-site CG water model were developed to accurately reproduce these energies. Furthermore, to test the transferability of these newly developed parameters, we calculated the hydration free energies of the analogues of the amino acid side chains, which showed good agreement with reported experimental data. Additionally, we show the applicability of these models by performing self-assembly simulations of peptide amphiphiles. Overall, these models are transferable and can be used to study the self-assembly of various biomaterials and biomolecules to develop a mechanistic understanding of these processes.
Collapse
Affiliation(s)
- Esmat Mohammadi
- Department of Chemical Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Soumil Y Joshi
- Department of Chemical Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Sanket A Deshmukh
- Department of Chemical Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
| |
Collapse
|
12
|
Teboul V. Dynamic phase transition induced by active molecules in a supercooled liquid. Phys Rev E 2023; 108:024605. [PMID: 37723732 DOI: 10.1103/physreve.108.024605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 07/21/2023] [Indexed: 09/20/2023]
Abstract
The purpose of this work is to use active particles to investigate the effect of facilitation on supercooled liquids. To this end we examine the behavior of a model supercooled liquid that is doped with a mixture of active particles and slowed particles. To simulate the facilitation mechanism, the activated particles are subjected to a force that follows the mobility of their most mobile neighboring molecule, while the slowed particles experience a friction force. Upon activation, we observe a fluidization of the entire medium along with a significant increase in dynamic heterogeneity. This effect is reminiscent of the fluidization observed experimentally when introducing molecular motors into soft materials. Interestingly, when the characteristic time τ_{μ}, used to define the mobility in the facilitation mechanism, matches the physical time t^{*} that characterizes the spontaneous cooperativity of the material, we observe a phase transition accompanied by structural aggregation of the active molecules. This transition is characterized by a sharp increase in fluidization and dynamic heterogeneity.
Collapse
Affiliation(s)
- Victor Teboul
- Laboratoire de Photonique d'Angers EA 4464, Université d'Angers, Physics Department, 2 Bd Lavoisier, 49045 Angers, France
| |
Collapse
|
13
|
Seehamart K, Busayaporn W, Chanajaree R. Molecular adsorption and self-diffusion of NO 2, SO 2, and their binary mixture in MIL-47(V) material. RSC Adv 2023; 13:19207-19219. [PMID: 37362329 PMCID: PMC10289206 DOI: 10.1039/d3ra02724d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 06/18/2023] [Indexed: 06/28/2023] Open
Abstract
The loading dependence of self-diffusion coefficients (Ds) of NO2, SO2, and their equimolar binary mixture in MIL-47(V) have been investigated by using classical molecular dynamics (MD) simulations. The Ds of NO2 are found to be two orders of magnitude greater than SO2 at low loadings and temperatures, and its Ds decreases monotonically with loading. The Ds of SO2 exhibit two diffusion patterns, indicating the specific interaction between the gas molecules and the MIL-47(V) lattice. The maximum activation energy (Ea) in the pure component and in the mixture for SO2 are 16.43 and 18.35 kJ mol-1, and for NO2 are 2.69 and 1.89 kJ mol-1, respectively. It is shown that SO2 requires more amount of energy than NO2 to increase the diffusion rate. The radial distribution functions (RDFs) of gas-gas and gas-lattice indicate that the Oh of MIL-47(V) are preferential adsorption site for both NO2 and SO2 molecules. However, the presence of the hydrogen bonding (HB) interaction between the O of SO2 and the H of MIL-47(V) and also their binding angle (θ(OHC)) of 120° with the linkers of lattice indicate a stronger binding interaction between the SO2 and the MIL-47(V), but it does not occur with NO2. The jump-diffusion of SO2 between adsorption sites within the lattice has been confirmed by the 2D density distribution plots. Moreover, the extraordinarily high Sdiff for NO2/SO2 of 623.4 shows that NO2 can diffuse through the MIL-47(V) significantly faster than SO2, especially at low loading and temperature.
Collapse
Affiliation(s)
- Kompichit Seehamart
- Department of Applied Physics, Faculty of Engineering, Rajamangala University of Technology Isan Khon Kaen Campus Khon Kaen 40000 Thailand
| | - Wutthikrai Busayaporn
- Synchrotron Light Research Institute (Public Organization) Nakhon Ratchasima 30000 Thailand
| | - Rungroj Chanajaree
- Metallurgy and Materials Science Research Institfute (MMRI), Chulalongkorn University Bangkok 10330 Thailand
| |
Collapse
|
14
|
Song J, Liu L, Cai S. Water desalination through FAU zeolite studied by using molecular dynamics simulations. J Mol Liq 2023. [DOI: 10.1016/j.molliq.2023.121683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
|
15
|
You J, Zheng Z, Cheng X, Li H, Fu C, Luo L, Wei G, Shen S, Yan X, Zhang J. Insight into Oxygen Transport in Solid and High-Surface-Area Carbon Supports of Proton Exchange Membrane Fuel Cells. ACS APPLIED MATERIALS & INTERFACES 2023; 15:21457-21466. [PMID: 37070714 DOI: 10.1021/acsami.3c01631] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Understanding the oxygen transport mechanism through an ionomer film that covered the catalyst surface is essential for reducing local oxygen transport resistance and improving the low Pt-loading proton exchange membrane fuel cell performance. Besides the ionomer material, the carbon supports, upon which ionomers and catalyst particles are dispersed, also play a crucial role in local oxygen transport. Increasing attention has been paid to the effects of carbon supports on local transport, but the detailed mechanism is still unclear. Herein, the local oxygen transports based on conventional solid carbon (SC) and high-surface-area carbon (HSC) supports are investigated by molecular dynamics simulations. It is found that oxygen diffuses through the ionomer film that covered the SC supports via "effective diffusion" and "ineffective diffusion". The former denotes the process by which oxygen diffuses directly from the ionomer surface to the Pt upper surface through small and concentrated regions. In contrast, ineffective diffusion suffers more restrictions by both carbon- and Pt-dense layers, and thus, the oxygen pathways are long and tortuous. The HSC supports exhibit larger transport resistance relative to SC supports due to the existence of micropores. Also, the major transport resistance originates from the carbon-dense layer as it inhibits oxygen from diffusing downward and migrating toward the pore opening, while the oxygen transport inside the pore is facile along the pore's inner surface, which leads to a specific and short diffusion pathway. This work provides insight into oxygen transport behavior with SC and HSC supports, which is the basis for the development of high-performance electrodes with low local transport resistance.
Collapse
Affiliation(s)
- Jiabin You
- Institute of Fuel Cells, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Zhifeng Zheng
- Institute of Fuel Cells, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xiaojing Cheng
- Institute of Fuel Cells, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Huiyuan Li
- Institute of Fuel Cells, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Cehuang Fu
- Institute of Fuel Cells, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Liuxuan Luo
- Institute of Fuel Cells, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Guanghua Wei
- SJTU-Paris Tech Elite Institute of Technology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Shuiyun Shen
- Institute of Fuel Cells, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xiaohui Yan
- Institute of Fuel Cells, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Junliang Zhang
- Institute of Fuel Cells, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
- MOE Key Laboratory of Power & Machinery Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| |
Collapse
|
16
|
Shi J, Zhou X, Jia P, Cai K. Ion Separation Together with Water Purification via a New Type of Nanotube: A Molecular Dynamics Study. Int J Mol Sci 2023; 24:ijms24076677. [PMID: 37047650 PMCID: PMC10094855 DOI: 10.3390/ijms24076677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 02/20/2023] [Accepted: 02/24/2023] [Indexed: 04/14/2023] Open
Abstract
We propose a CNT-based concentric twin tube (CTT) as nanochannels for both water purification and ion separation at the nanoscale. In the model, a source reservoir dealing with the solution connects three containers via the CTT that has three subchannels for mass transfer. Before entering the three subchannels, the solution in the separating zone will form three layers (the aqua cations, water, and the aqua anions, respectively) by applying a charged capacitor with the two electrodes parallel to the flow direction of the solution. Under an electric field with moderate intensity, the three subchannels in the CTT have stable configurations for mass transfer. Since the water and the two types of aqua ions are collected by three different containers, the present model can realize both ion separation and water purification. The mass transfer in the subchannels will be sped up by an external pressure exerted on the solution in the source reservoir. The physical properties of the model, e.g., water purification speed, are analyzed with respect to the effects of the electric field, the size of CTT, and the concentration of solute, such as NaCl.
Collapse
Affiliation(s)
- Jiao Shi
- Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas, Ministry of Education, Northwest A&F University, Yangling 712100, China
- College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling 712100, China
| | - Xin Zhou
- College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling 712100, China
| | - Pan Jia
- School of Science, Harbin Institute of Technology, Shenzhen 518055, China
| | - Kun Cai
- School of Science, Harbin Institute of Technology, Shenzhen 518055, China
| |
Collapse
|
17
|
Loos SAM, Arabha S, Rajabpour A, Hassanali A, Roldán É. Nonreciprocal forces enable cold-to-hot heat transfer between nanoparticles. Sci Rep 2023; 13:4517. [PMID: 36934145 PMCID: PMC10024720 DOI: 10.1038/s41598-023-31583-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 03/14/2023] [Indexed: 03/20/2023] Open
Abstract
We study the heat transfer between two nanoparticles held at different temperatures that interact through nonreciprocal forces, by combining molecular dynamics simulations with stochastic thermodynamics. Our simulations reveal that it is possible to construct nano refrigerators that generate a net heat transfer from a cold to a hot reservoir at the expense of power exerted by the nonreciprocal forces. Applying concepts from stochastic thermodynamics to a minimal underdamped Langevin model, we derive exact analytical expressions predictions for the fluctuations of work, heat, and efficiency, which reproduce thermodynamic quantities extracted from the molecular dynamics simulations. The theory only involves a single unknown parameter, namely an effective friction coefficient, which we estimate fitting the results of the molecular dynamics simulation to our theoretical predictions. Using this framework, we also establish design principles which identify the minimal amount of entropy production that is needed to achieve a certain amount of uncertainty in the power fluctuations of our nano refrigerator. Taken together, our results shed light on how the direction and fluctuations of heat flows in natural and artificial nano machines can be accurately quantified and controlled by using nonreciprocal forces.
Collapse
Affiliation(s)
- Sarah A M Loos
- Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge, CB3 0WA, UK.
- ICTP - International Centre for Theoretical Physics, Strada Costiera, 11, 34151, Trieste, Italy.
| | - Saeed Arabha
- Department of Mechanical Engineering, Lassonde School of Engineering, York University, Toronto, Canada
- Advanced Simulation and Computing Laboratory (ASCL), Imam Khomeini International University, Qazvin, Iran
| | - Ali Rajabpour
- Advanced Simulation and Computing Laboratory (ASCL), Imam Khomeini International University, Qazvin, Iran
- School of Nano Science, Institute for Research in Fundamental Sciences (IPM), Tehran, Iran
| | - Ali Hassanali
- ICTP - International Centre for Theoretical Physics, Strada Costiera, 11, 34151, Trieste, Italy
| | - Édgar Roldán
- ICTP - International Centre for Theoretical Physics, Strada Costiera, 11, 34151, Trieste, Italy
| |
Collapse
|
18
|
Oliveira MP, Hünenberger PH. Influence of the Lennard-Jones Combination Rules on the Simulated Properties of Organic Liquids at Optimal Force-Field Parametrization. J Chem Theory Comput 2023; 19:2048-2063. [PMID: 36920838 PMCID: PMC10100539 DOI: 10.1021/acs.jctc.2c01170] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
Abstract
We recently introduced the CombiFF scheme [Oliveira et al., J. Chem. Theory Comput. 2020, 16, 7525], an approach for the automated refinement of force-field parameters against experimental condensed-phase data for large compound families. Using this scheme, once the time-consuming task of target-data selection and curation has been performed, the force-field optimization itself is both straightforward and fast. As a result, CombiFF provides an ideal framework for evaluating the influence of functional-form decisions on the accuracy of a force field at an optimal level of parametrization. We already used this approach to assess the effect of using an all-atom representation compared to united-atom representations in the force field [Oliveira et al., J. Chem. Theory Comput. 2022, 18, 6757]. Here, CombiFF is applied to assess the effect of three Lennard-Jones combination rules, geometric-mean (GM), Lorentz-Berthelot (LB), or Waldman-Hagler (WH), on the simulated properties of organic liquids. The comparison is performed in terms of the experimental liquid density ρliq, vaporization enthalpy ΔHvap, surface-tension coefficient γ, static relative dielectric permittivity ϵ, and self-diffusion coefficient D. The calibrations of the three force-field variants are carried out independently against 2044 experimental values for ρliq, and ΔHvap concerning 1516 compounds. The resulting root-mean-square deviations from experiment are 30.0, 26.9, and 36.7 kg m-3 for ρliq and 2.8, 2.8, and 2.9 kJ mol-1 for ΔHvap, when applying the GM, LB, and WH combination rules, respectively. In terms of these (and the other) properties, the three combination rules perform comparatively well, with the GM and LB results being more similar to each other and slightly more accurate compared to experiment. In contrast, the use of distinct combination rules for the parameter calibration and property calculation leads to much larger errors.
Collapse
Affiliation(s)
- Marina P Oliveira
- Laboratorium für Physikalische Chemie, ETH Zürich, CH-8093 Zürich, Switzerland
| | | |
Collapse
|
19
|
A revised Lennard-Jones potential for bubble nucleation study of argon based on the molecular dynamics simulation method. J Mol Liq 2023. [DOI: 10.1016/j.molliq.2022.121094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
20
|
Shi L, Hu C, Yi C, Bai M, Lyu J, Gao L. A study of how solid–liquid interactions affect flow resistance and heat transfer at different temperatures based on molecular dynamics simulations. Phys Chem Chem Phys 2023; 25:813-821. [DOI: 10.1039/d2cp03905b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The heat transfer performance is improved as surface temperature increases, but the rise of surface temperature increases the flow resistance when solid–liquid interaction is weak but decreases the flow resistance when solid–liquid interaction is strong.
Collapse
Affiliation(s)
- Lin Shi
- Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education, School of Energy and Power Engineering, Dalian University of Technology, Dalian 116024, China
| | - Chengzhi Hu
- Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education, School of Energy and Power Engineering, Dalian University of Technology, Dalian 116024, China
| | - Changli Yi
- Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education, School of Energy and Power Engineering, Dalian University of Technology, Dalian 116024, China
| | - Minli Bai
- Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education, School of Energy and Power Engineering, Dalian University of Technology, Dalian 116024, China
| | - Jizu Lyu
- Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education, School of Energy and Power Engineering, Dalian University of Technology, Dalian 116024, China
| | - Linsong Gao
- Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education, School of Energy and Power Engineering, Dalian University of Technology, Dalian 116024, China
| |
Collapse
|
21
|
You J, Cheng X, Li H, Yin J, Yan X, Wei G, Shen S, Zhang J. Innovative Insight into O 2/N 2 Permeation Behavior through an Ionomer Film in Cathode Catalyst Layers of Polymer Electrolyte Membrane Fuel Cells. J Phys Chem Lett 2022; 13:11444-11453. [PMID: 36468972 DOI: 10.1021/acs.jpclett.2c03210] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
It is crucial to clarify the permeation behavior of O2 through the ionomer film for enhancing local O2 transport in cathodes of fuel cells. However, all existing studies mainly deal with pure O2 rather than air. Herein, the permeation behavior of the O2/N2 mixture through the ionomer film has been well explored in view of molecular bond length variations by molecular dynamics simulations. The bond lengths for O2 and N2 are shortened under a low hydration level when permeating through a dense layer with small free voids while no obvious change occurs at higher hydration. In the bulk ionomer region, O2 molecules residing in water domains are energetically unstable because the bond lengths deviate far from the equilibrium length; thus, O2 diffuses through the interfacial or hydrophobic regions. N2 molecules show similar properties with O2. This study provides a novel perspective on the permeation behavior of O2 and N2 through the ionomer film, which definitely benefits enhancing local O2 transport.
Collapse
Affiliation(s)
- Jiabin You
- Institute of Fuel Cells, School of Mechanical Engineering, Shanghai Jiao Tong University, 200240Shanghai, China
| | - Xiaojing Cheng
- Institute of Fuel Cells, School of Mechanical Engineering, Shanghai Jiao Tong University, 200240Shanghai, China
| | - Huiyuan Li
- Institute of Fuel Cells, School of Mechanical Engineering, Shanghai Jiao Tong University, 200240Shanghai, China
| | - Jiewei Yin
- Institute of Fuel Cells, School of Mechanical Engineering, Shanghai Jiao Tong University, 200240Shanghai, China
| | - Xiaohui Yan
- Institute of Fuel Cells, School of Mechanical Engineering, Shanghai Jiao Tong University, 200240Shanghai, China
| | - Guanghua Wei
- SJTU-Paris Tech Elite Institute of Technology, Shanghai Jiao Tong University, 200240Shanghai, China
| | - Shuiyun Shen
- Institute of Fuel Cells, School of Mechanical Engineering, Shanghai Jiao Tong University, 200240Shanghai, China
| | - Junliang Zhang
- Institute of Fuel Cells, School of Mechanical Engineering, Shanghai Jiao Tong University, 200240Shanghai, China
- MOE Key Laboratory of Power & Machinery Engineering, Shanghai Jiao Tong University, 200240Shanghai, China
| |
Collapse
|
22
|
Molecular dynamics study on the interfacial characteristics in the process of sub/supercritical evaporation. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.120693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
23
|
Mechanism of Hexane Displaced by Supercritical Carbon Dioxide: Insights from Molecular Simulations. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27238340. [PMID: 36500433 PMCID: PMC9736652 DOI: 10.3390/molecules27238340] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 11/21/2022] [Accepted: 11/23/2022] [Indexed: 12/02/2022]
Abstract
Supercritical carbon dioxide (sCO2) has great potential for displacing shale oil as a result of its high solubility and low surface tension and viscosity, but the underlying mechanisms have remained unclear up to now. By conducting equilibrium molecular dynamics (EMD) simulations, we found that the displacing process could be divided into three steps: the CO2 molecules were firstly injected in the central region of shale slit, then tended to adsorb on the SiO2-OH wall surface and mix with hexane, resulting in loose hexane layer on the shale surface, and finally displaced hexane from the wall due to strong interactions between CO2 and wall. In that process, the displacing velocity and efficiency of hexane exhibit parabolic and increased trends with pressure, respectively. To gain deep insights into this phenomenon, we further performed non-equilibrium molecular dynamics (NEMD) simulations and found that both the Onsager coefficients of CO2 and hexane were correlated to increase with pressure, until the diffusion rate of hexane being suppressed by the highly dense distribution of CO2 molecules at 12 MPa. The rapid transportation of CO2 molecules in the binary components (CO2 and hexane) actually promoted the hexane diffusion, which facilitated hexane flowing out of the nanochannel and subsequently enhanced oil recovery efficiency. The displacing process could occur effectively at pressures higher than 7.5 MPa, after which the interaction energies of the CO2-wall were stronger than that of the hexane-wall. Taking displacing velocity and efficiency and hexane diffusion rate into consideration, the optimal injection pressure was found at 10.5 MPa in this work. This study provides detailed insights into CO2 displacing shale oil and is in favor of deepening the understanding of shale oil exploitation and utilization.
Collapse
|
24
|
Yen TH, Chen YL. Analysis of Gas Nanoclusters in Water Using All-Atom Molecular Dynamics. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:13195-13205. [PMID: 36255233 DOI: 10.1021/acs.langmuir.2c02042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The Young-Laplace equation suggests that nanosized gas clusters would dissolve under the effects of perturbation. The fact that nanobubbles are observed raises questions as to the mechanism underlying their stability. In the current study, we used all-atom molecular dynamics simulations to investigate the gas-water interfacial properties of gas clusters. We employed the instantaneous coarse-graining method to define the fluctuating boundaries and analyze the deformation of gas clusters. Fourier transform analysis of the cluster morphology revealed that the radius and morphology deformation variations exhibit power law relationships with the vibrational frequency, indicating that the surface energy dissipated through morphology variations. Increasing pressure in the liquid region was found to alter the network of water molecules at the interface, whereas increasing pressure in the gas region did not exhibit this effect. The overall gas concentration was oversaturated and proportional to the gas density inside the clusters. However, the result of comparison with Henry's law reveals that the gas pressure at the interface reduced by the interfacial effects is much lower than that inside the gas region, thus reducing the demanding degree of oversaturation. Originating from the interfacial charge allocation, the magnitude of the electrostatic stress is greater than that of the gas pressure inside the cluster. However, the magnitude of the reversed tension induced by electrostatic stress is far below the value of interfacial tension. The potential of mean force (PMF) profiles revealed that a barrier potential at the interface hindered gas particles from escaping the cluster. Several effects contribute to stabilizing the gas clusters in water, including high-frequency morphological deformation, electrostatic stress, reduced interfacial tension, and gas oversaturation conditions. Our results suggest that gas clusters can exist in water under gas oversaturation conditions in the absence of hydrophobic contaminants or pinning charges at interfaces.
Collapse
Affiliation(s)
- Tsu-Hsu Yen
- Department of Marine Science, R.O.C. Naval Academy, Zuoying, Kaohsiung, Taiwan, R.O.C.813
| | - Yeng-Long Chen
- Institute of Physics, Academia Sinica, Taipei, Taiwan, R.O.C.11529
- Department of Chemical Engineering, National Tsing-Hua University, Hsinchu, Taiwan, R.O.C30013
- Physics Division, National Center for Theoretical Sciences, Taipei, Taiwan, R.O.C10617
| |
Collapse
|
25
|
Song J, Liu L, Hong Y. High interfacial resistances of CH4 and CO2 transport through Metal-Organic framework 5 (MOF-5). Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.121895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
|
26
|
Cai S, Li X, Yu L, Zhang L, Huo E. Thermodynamic and mass transport properties of R1234ze(E) and R32 mixtures at the liquid-vapor interface: A molecular dynamics study. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.120112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
27
|
Nucleate boiling of thin liquid films on nanostructured surfaces with hybrid wettability using molecular dynamics simulation. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.120272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
28
|
Li D, Zheng Y, Zhang H, Ye H. Self-Bending Behavior and Varying Bending Stiffness of Black Phosphorus/Molybdenum Disulfide (BP/MoS 2) Heterostructure. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:3635. [PMID: 36296824 PMCID: PMC9607561 DOI: 10.3390/nano12203635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 10/09/2022] [Accepted: 10/12/2022] [Indexed: 06/16/2023]
Abstract
Vertically-stacked black phosphorus/molybdenum disulfide (BP/MoS2) heterostructures have broad prospects in flexible electronics. Bending is a common and highly concerned deformation for these flexible devices. However, the discrepancy in structures and properties among the components of 2D heterostructures often induces complex bending deformations. Here, the bending behaviors of BP, MoS2 and BP/MoS2 are investigated based on a molecular dynamics simulation. Compared with the constant bending stiffness of individual BP and MoS2, that of BP/MoS2 varies with the bending angle. Notably, a self-bending configuration induced by the lattice mismatch and size difference is found in BP/MoS2. The corresponding self-bending amplitude depends on the degree of size difference of each component and the "soft/hard" competition between them. Moreover, the size difference leads to a weakened bending stiffness, which is ascribed to the reduction in interlayer interaction. A prediction formula is proposed to evaluate the bending stiffness of BP/MoS2 with the size difference. This finding reveals novel ways for regulating the bending properties of 2D heterostructures, including the bending angle, characteristic size and stacking order. It offers an effective strategy for designing flexible devices with tunable bending performance.
Collapse
|
29
|
Jing B, Liu Y, Liu C. Molecular dynamics simulations of R32/R134a boiling on nanostructured surfaces. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.119711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
30
|
Mocci F, de Villiers Engelbrecht L, Olla C, Cappai A, Casula MF, Melis C, Stagi L, Laaksonen A, Carbonaro CM. Carbon Nanodots from an In Silico Perspective. Chem Rev 2022; 122:13709-13799. [PMID: 35948072 PMCID: PMC9413235 DOI: 10.1021/acs.chemrev.1c00864] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Carbon nanodots (CNDs) are the latest and most shining rising stars among photoluminescent (PL) nanomaterials. These carbon-based surface-passivated nanostructures compete with other related PL materials, including traditional semiconductor quantum dots and organic dyes, with a long list of benefits and emerging applications. Advantages of CNDs include tunable inherent optical properties and high photostability, rich possibilities for surface functionalization and doping, dispersibility, low toxicity, and viable synthesis (top-down and bottom-up) from organic materials. CNDs can be applied to biomedicine including imaging and sensing, drug-delivery, photodynamic therapy, photocatalysis but also to energy harvesting in solar cells and as LEDs. More applications are reported continuously, making this already a research field of its own. Understanding of the properties of CNDs requires one to go to the levels of electrons, atoms, molecules, and nanostructures at different scales using modern molecular modeling and to correlate it tightly with experiments. This review highlights different in silico techniques and studies, from quantum chemistry to the mesoscale, with particular reference to carbon nanodots, carbonaceous nanoparticles whose structural and photophysical properties are not fully elucidated. The role of experimental investigation is also presented. Hereby, we hope to encourage the reader to investigate CNDs and to apply virtual chemistry to obtain further insights needed to customize these amazing systems for novel prospective applications.
Collapse
Affiliation(s)
- Francesca Mocci
- Department
of Chemical and Geological Sciences, University
of Cagliari, I-09042 Monserrato, Italy,
| | | | - Chiara Olla
- Department
of Physics, University of Cagliari, I-09042 Monserrato, Italy
| | - Antonio Cappai
- Department
of Physics, University of Cagliari, I-09042 Monserrato, Italy
| | - Maria Francesca Casula
- Department
of Mechanical, Chemical and Materials Engineering, University of Cagliari, Via Marengo 2, IT 09123 Cagliari, Italy
| | - Claudio Melis
- Department
of Physics, University of Cagliari, I-09042 Monserrato, Italy
| | - Luigi Stagi
- Department
of Chemistry and Pharmacy, Laboratory of Materials Science and Nanotechnology, University of Sassari, Via Vienna 2, 07100 Sassari, Italy
| | - Aatto Laaksonen
- Department
of Chemical and Geological Sciences, University
of Cagliari, I-09042 Monserrato, Italy,Department
of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden,State Key
Laboratory of Materials-Oriented and Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China,Centre
of Advanced Research in Bionanoconjugates and Biopolymers, PetruPoni Institute of Macromolecular Chemistry, Aleea Grigore Ghica-Voda 41A, 700487 Iasi, Romania,Division
of Energy Science, Energy Engineering, Luleå
University of Technology, Luleå 97187, Sweden,
| | | |
Collapse
|
31
|
Qiang W, Lan Z, Du B, Ren W, Xu W, Wen R, Ma X. Enrichment Effects Induced by Non-uniform Wettability Surfaces in the Presence of Non-condensable Gas: A Molecular Dynamics Simulation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:10192-10201. [PMID: 35959936 DOI: 10.1021/acs.langmuir.2c01264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
For vapor condensation, the control of heterogeneous nucleation and spatial distribution of nuclei are crucial for regulating droplet dynamics and improving condensation efficiency. However, due to the complex characteristics of multicomponent, multiphase, and multiscale, the underlying mechanism of mixed vapor condensation remains unclear, especially at the nucleation stage. In this paper, we focus on the enrichment effects of non-uniform wettability surfaces by molecular dynamics simulation, which could intensify the droplet nucleation and growth processes in a water-air mixed system. The results clarify the inhibitory effect of non-condensable gas on droplet nucleation and prove that only 1% of non-condensable gas could reduce one half of the condensation performance from a molecular perspective. Furthermore, non-uniform surfaces are designed to promote the efficient enrichment of vapor molecules on nucleation sites, and the synergistic effect of hydrophilic and hydrophobic regions is proposed. In addition, the non-uniform wettability surfaces are characterized by varying the proportion and dispersion of hydrophilic regions. The results reveal that an optimal proportion of hydrophilic region (R = 5/6) could furnish the non-uniform surface with the best transfer performance. Moreover, the enhancement of condensation performance can also be achieved through the dispersed arrangement of hydrophilic regions. The results provide guidance for the optimized design of functionalized surfaces with enhanced mixed vapor condensation.
Collapse
Affiliation(s)
- Weili Qiang
- State Key Laboratory of Fine Chemicals, Liaoning Key Laboratory of Clean Utilization of Chemical Resources, Institute of Chemical Engineering, Dalian University of Technology, Dalian 116024, PR China
| | - Zhong Lan
- State Key Laboratory of Fine Chemicals, Liaoning Key Laboratory of Clean Utilization of Chemical Resources, Institute of Chemical Engineering, Dalian University of Technology, Dalian 116024, PR China
| | - Bingang Du
- State Key Laboratory of Fine Chemicals, Liaoning Key Laboratory of Clean Utilization of Chemical Resources, Institute of Chemical Engineering, Dalian University of Technology, Dalian 116024, PR China
| | - Wenzhi Ren
- State Key Laboratory of Fine Chemicals, Liaoning Key Laboratory of Clean Utilization of Chemical Resources, Institute of Chemical Engineering, Dalian University of Technology, Dalian 116024, PR China
| | - Wei Xu
- State Key Laboratory of Fine Chemicals, Liaoning Key Laboratory of Clean Utilization of Chemical Resources, Institute of Chemical Engineering, Dalian University of Technology, Dalian 116024, PR China
| | - Rongfu Wen
- State Key Laboratory of Fine Chemicals, Liaoning Key Laboratory of Clean Utilization of Chemical Resources, Institute of Chemical Engineering, Dalian University of Technology, Dalian 116024, PR China
| | - Xuehu Ma
- State Key Laboratory of Fine Chemicals, Liaoning Key Laboratory of Clean Utilization of Chemical Resources, Institute of Chemical Engineering, Dalian University of Technology, Dalian 116024, PR China
| |
Collapse
|
32
|
Mercier F, Delhaye G, Teboul V. Activation induced fluidization of a confined viscous liquid. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.119545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
33
|
|
34
|
Liu T, Rahman MH, Menezes PL, Martini A. Effect of Ion Pair on Contact Angle for Phosphonium Ionic Liquids. J Phys Chem B 2022; 126:4354-4363. [PMID: 35666944 DOI: 10.1021/acs.jpcb.2c01989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The wettability of ionic liquids (ILs) is relevant to their use in various applications. However, a mechanistic understanding of how the cation-anion pair affects wettability is still evolving. Here, focusing on phosphonium ILs, wettability was characterized in terms of contact angle using experiments and classical molecular dynamics simulations. Both experiments and simulations showed that the contact angle was affected by the anion and increased as benzoate < salicylate < saccharinate. Further, the simulations showed that the contact angle decreased with increasing cation alkyl chain length for these anions paired with five different tetra-alkyl-phosphonium cations. The trends were explained in terms of adhesive and cohesive energies in the simulations and then correlated to the atomic scale differences between the anions and the cations.
Collapse
Affiliation(s)
- Ting Liu
- Department of Mechanical Engineering, University of California Merced, 5200 Lake Road, Merced, California 95343, United States
| | - Md Hafizur Rahman
- Department of Mechanical Engineering, University of Nevada Reno, 1664 North Virginia Street, Reno, Nevada 89557, United States
| | - Pradeep L Menezes
- Department of Mechanical Engineering, University of Nevada Reno, 1664 North Virginia Street, Reno, Nevada 89557, United States
| | - Ashlie Martini
- Department of Mechanical Engineering, University of California Merced, 5200 Lake Road, Merced, California 95343, United States
| |
Collapse
|
35
|
Töpfer K, Upadhyay M, Meuwly M. Quantitative molecular simulations. Phys Chem Chem Phys 2022; 24:12767-12786. [PMID: 35593769 PMCID: PMC9158373 DOI: 10.1039/d2cp01211a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Accepted: 04/30/2022] [Indexed: 11/21/2022]
Abstract
All-atom simulations can provide molecular-level insights into the dynamics of gas-phase, condensed-phase and surface processes. One important requirement is a sufficiently realistic and detailed description of the underlying intermolecular interactions. The present perspective provides an overview of the present status of quantitative atomistic simulations from colleagues' and our own efforts for gas- and solution-phase processes and for the dynamics on surfaces. Particular attention is paid to direct comparison with experiment. An outlook discusses present challenges and future extensions to bring such dynamics simulations even closer to reality.
Collapse
Affiliation(s)
- Kai Töpfer
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056 Basel, Switzerland.
| | - Meenu Upadhyay
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056 Basel, Switzerland.
| | - Markus Meuwly
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056 Basel, Switzerland.
| |
Collapse
|
36
|
Adaptive intermolecular interaction parameters for accurate Mixture Density Functional Theory calculations. Chem Eng Sci 2022. [DOI: 10.1016/j.ces.2022.117628] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
37
|
Wang G, Wang Z, Cao W, Liu Y, Zheng B, Deng Y. Identifying promising covalent organic frameworks for HCHO/O2 + N2 adsorption from indoor air pollution using high-throughput computational screening. COMPUT THEOR CHEM 2022. [DOI: 10.1016/j.comptc.2022.113655] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
|
38
|
Wang WB, Ohta R, Kambara M. Study on liquid-like SiGe cluster growth during co-condensation from supersaturated vapor mixtures by molecular dynamics simulation. Phys Chem Chem Phys 2022; 24:7442-7450. [PMID: 35274111 DOI: 10.1039/d1cp05589e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Based on the co-condensation processes in the Si-Ge system upon cooling, as determined by molecular dynamics (MD) simulation, we explored the mixed cluster growth dynamics and structural properties leading to the synthesis of liquid-like SiGe nanoclusters. The results indicated that the cluster size quickly increased to large clusters by the coalescence of transient small clusters in the growth stage during co-condensation. The transient clusters at different temperatures were verified to have slightly Si-rich compositions and liquid-like structures. The coalescence of such nanoclusters at high temperatures led to spherical clusters with homogeneous intermixing. However, irregularly shaped clusters with attached mixed parts were obtained owing to incomplete coalescence at low temperatures. Ge atoms tended to move to the cluster surface to exploit their energetically favorable state during the restructuring process, leading to slightly Ge-rich components on the cluster surface. The degree of intermixing for SiGe nanoclusters was related to cluster size. Generally, small clusters appeared to be more segregated during restructuring.
Collapse
Affiliation(s)
- Wen-Bo Wang
- Department of Materials Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo 113-0033, Japan.
| | - Ryoshi Ohta
- Department of Materials Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo 113-0033, Japan.
| | - Makoto Kambara
- Department of Materials Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo 113-0033, Japan.
| |
Collapse
|
39
|
Ogrin P, Urbic T. Isothermal-isobaric algorithm to study the effects of rotational degrees of freedom-Benz water model. J Mol Liq 2022; 349:118152. [PMID: 37727581 PMCID: PMC10508877 DOI: 10.1016/j.molliq.2021.118152] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have developed isothermal-isobaric algorithm for non-equilibrium Monte Carlo simulations. As first we have shown that the new method correctly predict density by comparing it to the density determined in canonical Monte Carlo simulations through the virial pressure. The new method was then used to study the effect of translational and rotational degrees of freedom on the structural and thermodynamic properties of the simple Mercedes-Benz water model. By holding one of the temperatures constant and varying the other one, we investigated how the position of the density maxima changes. We have observed that upon increase of rotational temperature the fluid become more Lennard-Jones like and the density maxima disappears.
Collapse
Affiliation(s)
- Peter Ogrin
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Vecna Pot 113, SI-1000 Ljubljana, Slovenia
| | - Tomaz Urbic
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Vecna Pot 113, SI-1000 Ljubljana, Slovenia
| |
Collapse
|
40
|
Munguía-Valadez J, Chávez-Rojo MA, Sambriski EJ, Moreno-Razo JA. The generalized continuous multiple step (GCMS) potential: model systems and benchmarks. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:184002. [PMID: 35090143 DOI: 10.1088/1361-648x/ac4fe8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 01/28/2022] [Indexed: 06/14/2023]
Abstract
The generalized continuous multiple step (GCMS) potential is presented in this work. Its flexible form allows forrepulsiveand/orattractivecontributions to be encoded through adjustable energy and length scales. The GCMS interaction provides a continuous representation of square-well, square-shoulder potentials and their variants for implementation in computer simulations. A continuous and differentiable energy representation is required to derive forces in conventional simulation algorithms. Molecular dynamics simulations are of particular interest when considering the dynamic properties of a system. The GCMS potential can mimic other interactions with a judicious choice of parameters due to the versatile sigmoid form. In this study, our benchmarks for the GCMS representation include triangular, Yukawa, Franzese, and Lennard-Jones potentials. Comparisons made with published data on volumetric phase diagrams, liquid structure, and diffusivity from model systems are in excellent agreement.
Collapse
Affiliation(s)
- Jorge Munguía-Valadez
- Departamento de Física, Universidad Autónoma Metropolitana-Iztapalapa, Avenida San Rafael Atlixco No. 186, Colonia Vicentina, Delegación Iztapalapa, Mexico City 09340 Mexico
| | - Marco Antonio Chávez-Rojo
- Facultad de Ciencias Químicas, Universidad Autónoma de Chihuahua, Circuito Universitario s/n, Campus II, Chihuahua, Chihuahua 31125, Mexico
| | - Edward John Sambriski
- Department of Chemistry, Delaware Valley University, 700 East Butler Avenue, Doylestown, PA 18901 United States of America
| | - José Antonio Moreno-Razo
- Departamento de Física, Universidad Autónoma Metropolitana-Iztapalapa, Avenida San Rafael Atlixco No. 186, Colonia Vicentina, Delegación Iztapalapa, Mexico City 09340 Mexico
| |
Collapse
|
41
|
Zhou W, Zhang Y, Wei J. Molecular Dynamics Study on the Combined Effects of the Nanostructure and Wettability of Solid Surfaces on Bubble Nucleation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:1223-1230. [PMID: 34995464 DOI: 10.1021/acs.langmuir.1c02992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
In this paper, molecular dynamics (MD) simulations are conducted to investigate the bubble nucleation process of liquid argon on surfaces with a nanostructure of different wettabilities. To account for the combined effects of the nanostructure and surface wettability on bubble nucleation, the variation of the bubble volume, the nucleation starting time, as well as the heat flux between the solid surface and fluid are examined. It is found that the position of bubble nucleation depends on the pillar wettability. Bubble nucleation occurs in the bulk of fluid when the pillar is hydrophilic, while it occurs on the pillar surface when the pillar is hydrophobic. Under an integrated influence of the free-energy barrier of nucleation and heat transfer, the nucleation occurs later as the wettability of the pillar gets weaker over surfaces with the hydrophilic pillar, while it occurs earlier as the wettability of the pillar gets weaker over surfaces with the hydrophobic pillar. Moreover, the peak heat flux decreases with the decrease of the pillar wettability over surfaces with the hydrophilic pillar, while it increases with the decrease of the pillar wettability over surfaces with the hydrophobic pillar, which can be explained from the perspective of the heat transfer efficiency and the timing of phase change occurrence. Finally, a new surface with mixed-wettable pillars is proposed, which is verified to be conducive to both bubble nucleation and heat transfer.
Collapse
Affiliation(s)
- Wenjing Zhou
- School of Chemical Engineering and Technology, Xi'an Jiaotong University, Xi'an 710049, P. R. China
| | - Yonghai Zhang
- School of Chemical Engineering and Technology, Xi'an Jiaotong University, Xi'an 710049, P. R. China
| | - Jinjia Wei
- School of Chemical Engineering and Technology, Xi'an Jiaotong University, Xi'an 710049, P. R. China
- State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an 710049, P. R. China
| |
Collapse
|
42
|
Chen W, Nagayama G. Quasi-Casimir coupling can induce thermal resonance of adsorbed liquid layers in a nanogap. Phys Chem Chem Phys 2022; 24:11758-11769. [DOI: 10.1039/d2cp01094a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In a vacuum nanogap, phonon heat transfer can be induced by quasi-Casimir coupling in the absence of electromagnetic fields. However, it is unknown whether phonons can be transmitted across a...
Collapse
|
43
|
Deng X, Zhang Q, Zhang Z, Li Q, Liu X. Adsorption and diffusion behavior of CO2/H2 mixture in calcite slit pores: A molecular simulation study. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2021.118306] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
44
|
Rabani R, Saidi MH, Joly L, Merabia S, Rajabpour A. Enhanced local viscosity around colloidal nanoparticles probed by equilibrium molecular dynamics simulations. J Chem Phys 2021; 155:174701. [PMID: 34742212 DOI: 10.1063/5.0065050] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Nanofluids-dispersions of nanometer-sized particles in a liquid medium-have been proposed for a wide variety of thermal management applications. It is known that a solid-like nanolayer of liquid of typical thicknesses of 0.5-1 nm surrounding the colloidal nanoparticles can act as a thermal bridge between the nanoparticle and the bulk liquid. Yet, its effect on the nanofluid viscosity has not been elucidated so far. In this article, we compute the local viscosity of the nanolayer using equilibrium molecular dynamics based on the Green-Kubo formula. We first assess the validity of the method to predict the viscosity locally. We apply this methodology to the calculation of the local viscosity in the immediate vicinity of a metallic nanoparticle for a wide range of solid-liquid interaction strength, where a nanolayer of thickness 1 nm is observed as a result of the interaction with the nanoparticle. The viscosity of the nanolayer, which is found to be higher than its corresponding bulk value, is directly dependent on the solid-liquid interaction strength. We discuss the origin of this viscosity enhancement and show that the liquid density increment alone cannot explain the values of the viscosity observed. Rather, we suggest that the solid-like structure of the distribution of the liquid atoms in the vicinity of the nanoparticle contributes to the nanolayer viscosity enhancement. Finally, we observe a failure of the Stokes-Einstein relation between viscosity and diffusion close to the wall, depending on the liquid-solid interaction strength, which we rationalize in terms of the hydrodynamic slip.
Collapse
Affiliation(s)
- Reza Rabani
- Center of Excellence in Energy Conversion (CEEC), School of Mechanical Engineering, Sharif University of Technology, Tehran 11155-9567, Iran
| | - Mohammad Hassan Saidi
- Center of Excellence in Energy Conversion (CEEC), School of Mechanical Engineering, Sharif University of Technology, Tehran 11155-9567, Iran
| | - Laurent Joly
- Univ Lyon, Univ Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622 Villeurbanne, France
| | - Samy Merabia
- Univ Lyon, Univ Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622 Villeurbanne, France
| | - Ali Rajabpour
- Advanced Simulation and Computing Laboratory (ASCL), Mechanical Engineering Department, Imam Khomeini International University, Qazvin, Iran
| |
Collapse
|
45
|
Wen B, Sun C, Luo Z, Lu X, Wang H, Bai B. A hydrogen bond-modulated soft nanoscale water channel for ion transport through liquid-liquid interfaces. SOFT MATTER 2021; 17:9736-9744. [PMID: 34643637 DOI: 10.1039/d1sm00899d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Ion transport through interfaces is of ubiquitous importance in many fields such as electrochemistry, emulsion stabilization, phase transfer catalysis, liquid-liquid extraction and enhanced oil recovery. However, the knowledge of interfacial structures that significantly affect ion transport through liquid-liquid interfaces is still lacking due to the difficulty of observing nanoscale interfaces. We studied here the evolution of interfacial structures during ion transport through the decane-water interface under different ionic concentrations and external forces using molecular dynamics simulations. The roles of hydrogen bonds in ion transport through interfaces are revealed. We identified a soft nanoscale channel during ion transport through liquid-liquid interfaces and the decane phase under specific external force. The stability of the water channel and the ion transport velocity both increase with ionic concentration due to the layered ordering structures of the water near the channel surface. We observed that the stability and connectivity of the water channel in the decane phase are remarkably improved both by the high increase of the number of hydrogen bonds in the water channel with increasing ionic concentration, and by the conformational change in water molecules near the water channel surface. Our discovery of a soft nanoscale water channel by molecular simulations implies that there is a potential stable passage for ion transport through liquid-liquid interfaces.
Collapse
Affiliation(s)
- Boyao Wen
- State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China.
| | - Chengzhen Sun
- State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China.
| | - Zhengyuan Luo
- State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China.
| | - Xi Lu
- Petroleum Exploration and Production Research Institute of Sinopec, Beijing, 100083, China
| | - Haibo Wang
- Petroleum Exploration and Production Research Institute of Sinopec, Beijing, 100083, China
| | - Bofeng Bai
- State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China.
| |
Collapse
|
46
|
|
47
|
Gelation of waxy crude oil system with ethylene-vinyl acetate on solid surface: A molecular dynamics study. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.115816] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
48
|
Entrance resistance of water transport into carbon nanotubes: Insights from molecular dynamics simulations. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.115739] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
49
|
Wu L, Shao W, Cao Q, Cui Z. Atomistic Insight into the Effects of Depositional Nanoparticle on Nanoscale Liquid Film Evaporation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:5202-5212. [PMID: 33881886 DOI: 10.1021/acs.langmuir.1c00149] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Nanoscale liquid film evaporation plays an essential role in many engineering applications. This study carries out molecular dynamics simulations on the effects of the depositional nanoparticle's wettability and volume in base fluid on the evaporation process to understand how the depositional nanoparticle affects the evaporation heat transfer. Increasing the nanoparticle's wettability can enhance the evaporation heat transfer process, and the enhancement effect of the hydrophobic surface is more remarkable than that of the hydrophilic surface. This because the increasing wettability causes more significant solid-liquid interaction. However, the potential energy of argon atoms at the liquid-vapor interface is almost unaffected by wettability. Moreover, when the depositional nanoparticle locates below the free liquid film, increasing the nanoparticle volume has a better heat transfer performance. As the volume increases, the heat transfer through the nanoparticle becomes more obvious, which effectively enhances the heat transfer at the solid-liquid interface and the liquid-vapor interface. The latent heat of phase change at the liquid-vapor interface is almost unchanged so that the evaporation can be enhanced. This research provides an understanding of the effects of depositional nanoparticles on nanoscale evaporation, which can impact several engineering applications, including devices' cooling and fluid transport.
Collapse
Affiliation(s)
- Ling Wu
- School of Energy and Power Engineering, Shandong University, Jinan 250061, Shandong Province China
| | - Wei Shao
- Institute of Thermal Science and Technology, Shandong University, Jinan 250061, Shandong Province China
| | - Qun Cao
- Shandong Institute of Advanced Technology, Jinan 250100, Shandong Province China
| | - Zheng Cui
- Institute of Thermal Science and Technology, Shandong University, Jinan 250061, Shandong Province China
- Shandong Institute of Advanced Technology, Jinan 250100, Shandong Province China
| |
Collapse
|
50
|
Banerjee T, Samanta A. Chemical computational approaches for optimization of effective surfactants in enhanced oil recovery. PHYSICAL SCIENCES REVIEWS 2021. [DOI: 10.1515/psr-2020-0098] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Abstract
The surfactant flooding becomes an attractive method among several Enhanced Oil Recovery (EOR) processes to improve the recovery of residual oil left behind in the reservoir after secondary oil recovery process. The designing of a new effective surfactant is a comparatively complex and often time consuming process as well as cost-effective due to its dependency on the crude oil and reservoir properties. An alternative chemical computational approach is focused in this article to optimize the performance of effective surfactant system for EOR. The molecular dynamics (MD), dissipative particle dynamics (DPD) and density functional theory (DFT) simulations are mostly used chemical computational approaches to study the behaviour in multiple phase systems like surfactant/oil/brine. This article highlighted a review on the impact of surfactant head group structure on oil/water interfacial property like interfacial tensions, interface formation energy, interfacial thickness by MD simulation. The effect of entropy in micelle formation has also discussed through MD simulation. The polarity, dipole moment, charge distribution and molecular structure optimization have been illustrated by DFT. A relatively new coarse-grained method, DPD is also emphasized the phase behaviour of surfactant/oil/brine as well as polymer-surfactant complex system.
Collapse
Affiliation(s)
- Tandrima Banerjee
- Department of Chemical Sciences , Indian Institute of Science Education and Research (IISER) Kolkata , West Bengal 741246 , India
| | - Abhijit Samanta
- School of Engineering and Applied Sciences , The Neotia University , Sarisha , West Bengal 743368 , India
| |
Collapse
|