1
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Arya V, Chaudhuri A, Bakli C. Passive fractionating mechanism for oil spill using shear-wettability modulation. NANOSCALE 2024; 16:13885-13894. [PMID: 38853508 DOI: 10.1039/d4nr01235f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Oil spillage and organic solvent leakage have been a frequent occurrence in recent years, which pose a significant threat not only to the aquatic ecosystems but also result in substantial economic burdens. This has necessitated the search for materials capable of separating oil from water at enhanced efficiency with superior mechanical and thermal properties. In this study, we conduct a set of systematic molecular dynamics simulations to investigate the potential of two-dimensional graphene-like channels under extreme confinement to achieve efficient oil-water separation. Effective modulation of the wetting characteristics of graphene-like surfaces juxtaposed with unconventional flow behavior at the nanoscale unveils differential interaction of water and oil molecules towards the wall, thereby resulting in distinct separation zones for varying compositions of the oil-water mixture. Such separation zones have been observed to be highly correlated with mixture temperature, which provides effective separation pathways across diverse environmental conditions. Our study offers a paradigm shift in oil-water separation strategies, which not only provides deeper insights into the equilibrium and dynamic behavior of a two-phase mixture but also holds immense implications for the development of smart, wettability-based oil separation devices.
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Affiliation(s)
- Vinay Arya
- Thermofluidics and Nanotechnology for Sustainable Energy Systems Laboratory, School of Energy Science and Engineering, Indian Institute of Technology Kharagpur, Kharagpur, India 721302.
| | - Abhirup Chaudhuri
- Department of Mechanical Engineering, Indian Institute of Technology Kharagpur, Kharagpur, India 721302
| | - Chirodeep Bakli
- Thermofluidics and Nanotechnology for Sustainable Energy Systems Laboratory, School of Energy Science and Engineering, Indian Institute of Technology Kharagpur, Kharagpur, India 721302.
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2
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Dong W, Dai Z, Liu L, Zhang Z. Toward Clean 2D Materials and Devices: Recent Progress in Transfer and Cleaning Methods. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2303014. [PMID: 38049925 DOI: 10.1002/adma.202303014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2023] [Revised: 08/30/2023] [Indexed: 12/06/2023]
Abstract
Two-dimensional (2D) materials have tremendous potential to revolutionize the field of electronics and photonics. Unlocking such potential, however, is hampered by the presence of contaminants that usually impede the performance of 2D materials in devices. This perspective provides an overview of recent efforts to develop clean 2D materials and devices. It begins by discussing conventional and recently developed wet and dry transfer techniques and their effectiveness in maintaining material "cleanliness". Multi-scale methodologies for assessing the cleanliness of 2D material surfaces and interfaces are then reviewed. Finally, recent advances in passive and active cleaning strategies are presented, including the unique self-cleaning mechanism, thermal annealing, and mechanical treatment that rely on self-cleaning in essence. The crucial role of interface wetting in these methods is emphasized, and it is hoped that this understanding can inspire further extension and innovation of efficient transfer and cleaning of 2D materials for practical applications.
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Affiliation(s)
- Wenlong Dong
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication and CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhaohe Dai
- Department of Mechanics and Engineering Science, State Key Laboratory for Turbulence and Complex Systems, College of Engineering, Peking University, Beijing, 100871, China
| | - Luqi Liu
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication and CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China
| | - Zhong Zhang
- CAS Key Laboratory of Mechanical Behavior and Design of Materials, Department of Modern Mechanics, University of Science and Technology of China, Hefei, 230027, China
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3
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Ruiz-Barragan S, Forbert H, Marx D. Anisotropic pressure effects on nanoconfined water within narrow graphene slit pores. Phys Chem Chem Phys 2023; 25:28119-28129. [PMID: 37818616 DOI: 10.1039/d3cp01687k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/12/2023]
Abstract
There is an increasing interest toward disclosing and explaining confinement effects on liquids, such as water or aqueous solutions, in slit pore setups. Particularly puzzling are the changes of physical and chemical properties in the nanoconfinement regime where no bulk-like water phase exists between the two interfacial water layers such that the density profile across the slit pore becomes highly stratified, ultimately leading to bilayer and monolayer water. These changes must be quantified with respect to some meaningful reference state of water, the most natural one being bulk water at the same pressure and temperature conditions. However, bulk water is a homogeneous liquid with isotropic properties, whereas water confined in slit pores is inhomogeneous, implying anisotropic properties as described by the perpendicular and parallel components of the respective tensors. In the case of pressure, the inhomogeneous nature of the setup results in a well-defined difference between the perpendicular and parallel pressure tensor components that is uniquely determined by the interfacial tension being a thermodynamic property. For bilayer water constrained in graphene slit pores that are only about 1 nm wide, we demonstrate that there exists a thermodynamic point where the pressure tensor of the inhomogeneous fluid, nanoconfined water, is effectively isotopic and the pressure is thus scalar as in the homogeneous fluid, bulk water. This specific point of vanishing effective interfacial tension is proposed to serve as a well-defined reference state to compare the properties of nanoconfined liquids to those of the corresponding bulk liquid at the same (isotropic) pressure and temperature conditions. In future work, this idea could be applied to assess confinement effects on chemical reactivity in aqueous solutions as well as to other nanoconfined liquids in other pores such as layered minerals.
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Affiliation(s)
- Sergi Ruiz-Barragan
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany.
| | - Harald Forbert
- Center for Solvation Science ZEMOS, Ruhr - Universität Bochum, 44780 Bochum, Germany
| | - Dominik Marx
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany.
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4
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Yan C, Zhao YX, Liu YW, He L. Kinetics of Nanobubbles in Tiny-Angle Twisted Bilayer Graphene. NANO LETTERS 2023; 23:8532-8538. [PMID: 37669559 DOI: 10.1021/acs.nanolett.3c02286] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/07/2023]
Abstract
Realization of high-quality van der Waals (vdWs) heterostructures by stacking two-dimensional (2D) layers requires atomically clean interfaces. Because of strong adhesion between the constituent layers, the vdWs forces could drive trapped contaminants together into submicron-size "bubbles", which leaves large interfacial areas atomically clean. Here, we study the kinetics of nanobubbles in tiny-angle twisted bilayer graphene (TBG) and our results reveal a substantial influence of the moiré superlattice on the motion of nanoscale interfacial substances. Our experiments indicate that the bubbles will mainly move along the triangular network of domain boundaries in the tiny-angle TBG when the sizes of the bubbles are comparable to that of an AA-stacking region. When the size of the bubble is smaller than that of an AA-stacking region, the bubble becomes motionless and is fixed in the AA-stacking region, because of its large out-of-plane corrugation.
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Affiliation(s)
- Chao Yan
- Center for Advanced Quantum Studies Department of Physics, Beijing Normal University, Beijing, 100875, China
- Key Laboratory of Multiscale Spin Physics, Ministry of Education, Beijing, 100875, China
| | - Ya-Xin Zhao
- Center for Advanced Quantum Studies Department of Physics, Beijing Normal University, Beijing, 100875, China
- Key Laboratory of Multiscale Spin Physics, Ministry of Education, Beijing, 100875, China
| | - Yi-Wen Liu
- Center for Advanced Quantum Studies Department of Physics, Beijing Normal University, Beijing, 100875, China
- Key Laboratory of Multiscale Spin Physics, Ministry of Education, Beijing, 100875, China
| | - Lin He
- Center for Advanced Quantum Studies Department of Physics, Beijing Normal University, Beijing, 100875, China
- Key Laboratory of Multiscale Spin Physics, Ministry of Education, Beijing, 100875, China
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5
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Kateb M, Isacsson A. Nanoscale Elasto-Capillarity in the Graphene-Water System under Tension: Revisiting the Assumption of a Constant Wetting Angle. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:12610-12617. [PMID: 37624594 PMCID: PMC10501189 DOI: 10.1021/acs.langmuir.3c01259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 08/07/2023] [Indexed: 08/26/2023]
Abstract
Wetting highly compliant surfaces can cause them to deform. Atomically thin materials, such as graphene, can have exceptionally small bending rigidities, leading to elasto-capillary lengths of a few nanometers. Using large-scale molecular dynamics (MD), we have studied the wetting and deformation of graphene due to nanometer-sized water droplets, focusing on the wetting angle near the vesicle transition. Recent continuum theories for wetting of flexible membranes reproduce our MD results qualitatively well. However, we find that when the curvature is large at the triple-phase contact line, the wetting angle increases with decreasing tension. This is in contrast to existing macroscopic theories but can be amended by allowing for a variable wetting angle.
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Affiliation(s)
- Movaffaq Kateb
- Department of Physics, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
| | - Andreas Isacsson
- Department of Physics, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
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6
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Zhao Z, Jin Y, Zhou R, Sun C, Huang X. Unexpected Behavior in Thermal Conductivity of Confined Monolayer Water. J Phys Chem B 2023; 127:4090-4098. [PMID: 37105181 DOI: 10.1021/acs.jpcb.2c07506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
Monolayer water can be formed under extreme confinement and will present distinctive thermodynamic properties compared with bulk water. In this work, we perform molecular dynamics simulations to study the thermal conductivity of monolayer water confined in graphene channels, finding an unexpected way of thermal conductivity of monolayer water dependent on its number density, which has a close correlation with the structure of water. The monolayer water is in an amorphous state, and its thermal conductivity increases linearly with the area density when the water density is low at first. Then, the thermal conductivity increases as the number density of water rises, which is attributed to the formation of a crystal structure and the reduction of crystal defects as the number of water molecules increases. After reaching the zenith, the thermal conductivity decreases rapidly owing to the formation of a wrinkle structure of monolayer water with excessive water molecules, which weakens the phonon dispersion. Moreover, we further investigate the remarkable effects of the channel height on both the structure and thermal conductivity of monolayer water. In summary, this study demonstrates the close connection between the thermal conductivity of monolayer water and its structure, contributing to not only expanding the understanding of the thermodynamic property of nanoconfined water but also benefiting the engineering applications for nanofluidics.
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Affiliation(s)
- Zhixiang Zhao
- School of Urban Planning and Municipal Engineering, Xi'an Polytechnic University, Shaanxi 710048, China
| | - Yonghui Jin
- School of Urban Planning and Municipal Engineering, Xi'an Polytechnic University, Shaanxi 710048, China
| | - Runfeng Zhou
- State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Shaanxi 710049, China
| | - Chengzhen Sun
- State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Shaanxi 710049, China
| | - Xiang Huang
- School of Urban Planning and Municipal Engineering, Xi'an Polytechnic University, Shaanxi 710048, China
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7
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Das B, Ruiz-Barragan S, Marx D. Deciphering the Properties of Nanoconfined Aqueous Solutions by Vibrational Sum Frequency Generation Spectroscopy. J Phys Chem Lett 2023; 14:1208-1213. [PMID: 36716226 PMCID: PMC9923734 DOI: 10.1021/acs.jpclett.2c03409] [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: 11/09/2022] [Accepted: 12/21/2022] [Indexed: 06/18/2023]
Abstract
When confined between walls at nanometer distances, water exhibits surprisingly different properties with reference to bare interfacial water. Based on computer simulations, we demonstrate how vibrational sum frequency generation (VSFG) spectroscopy can be used-even with very mild symmetry breaking-to discriminate multilayer water in wide slit pores from both bilayer and monolayer water confined within molecularly narrow pores. Applying the technique, the VSFG lineshapes of monolayer, bilayer, and multilayer water are found to differ in characteristic ways, which is explained by their distinct density stratifications giving rise to different H-bonding patterns in the respective solvation layers.
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Affiliation(s)
- Banshi Das
- Lehrstuhl
für Theoretische Chemie, Ruhr-Universität
Bochum, 44780Bochum, Germany
| | - Sergi Ruiz-Barragan
- Lehrstuhl
für Theoretische Chemie, Ruhr-Universität
Bochum, 44780Bochum, Germany
- Departament
de Fisica, Universitat Politecnica de Catalunya, Rambla Sant Nebridi 22, 08222 Terrassa, Barcelona, Spain
| | - Dominik Marx
- Lehrstuhl
für Theoretische Chemie, Ruhr-Universität
Bochum, 44780Bochum, Germany
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8
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Majumdar J, Dasgupta S, Mandal S, Moid M, Jain M, Maiti PK. Does twist angle affect the properties of water confined inside twisted bilayer graphene? J Chem Phys 2023; 158:034501. [PMID: 36681635 DOI: 10.1063/5.0139256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Graphene nanoslit pores are used for nanofluidic devices, such as, in water desalination, ion-selective channels, ionic transistors, sensing, molecular sieving, blue energy harvesting, and protein sequencing. It is a strenuous task to prepare nanofluidic devices, because a small misalignment leads to a significant alteration in various properties of the devices. Here, we focus on the rotational misalignment between two parallel graphene sheets. Using molecular dynamics simulation, we probe the structure and dynamics of monolayer water confined inside graphene nanochannels for a range of commensurate twist angles. With SPC/E and TIP4P/2005 water models, our simulations reveal the independence of the equilibrium number density- n ∼ 13 nm-2 for SPC/E and n ∼ 11.5 nm-2 for TIP4P/2005- across twists. Based on the respective densities of the water models, the structure and dielectric constant are invariant of twist angles. The confined water structure at this density shows square ice ordering for SPC/E water only. TIP4P/2005 shows ordering at the vicinity of a critical density (n ∼ 12.5 nm-2). The average perpendicular dielectric constant of the confined water remains anomalously low (∼2 for SPC/E and ∼6 for TIP4P/2005) for the studied twist angles. We find that the friction coefficient of confined water molecules varies for small twist angles, while becoming independent for twists greater than 5.1°. Our results indicate that a small, angular misalignment will not impair the dielectric properties of monolayer water within a graphene slit-pore, but can significantly influence its dynamics.
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Affiliation(s)
- Jeet Majumdar
- Centre for Condensed Matter Theory, Department of Physics, Indian Institute of Science, Bangalore 560012, India
| | - Subhadeep Dasgupta
- Centre for Condensed Matter Theory, Department of Physics, Indian Institute of Science, Bangalore 560012, India
| | - Soham Mandal
- Centre for Condensed Matter Theory, Department of Physics, Indian Institute of Science, Bangalore 560012, India
| | - Mohd Moid
- Centre for Condensed Matter Theory, Department of Physics, Indian Institute of Science, Bangalore 560012, India
| | - Manish Jain
- Centre for Condensed Matter Theory, Department of Physics, Indian Institute of Science, Bangalore 560012, India
| | - Prabal K Maiti
- Centre for Condensed Matter Theory, Department of Physics, Indian Institute of Science, Bangalore 560012, India
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9
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Xu Z, Li H, Ma M. Accurate estimation of dynamical quantities for nonequilibrium nanoscale systems. Phys Rev E 2023; 107:014124. [PMID: 36797886 DOI: 10.1103/physreve.107.014124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 12/09/2022] [Indexed: 06/18/2023]
Abstract
Fluctuations of dynamical quantities are fundamental and inevitable. For the booming research in nanotechnology, huge relative fluctuation comes with the reduction of system size, leading to large uncertainty for the estimates of dynamical quantities. Thus, increasing statistical efficiency, i.e., reducing the number of samples required to achieve a given accuracy, is of great significance for accurate estimation. Here we propose a theory as a fundamental solution for such problem by constructing auxiliary path for each real path. The states on auxiliary paths constitute canonical ensemble and share the same macroscopic properties (NVT) with the initial states of the real path. By implementing the theory in molecular dynamics simulations, we obtain a nanoscale Couette flow field with an accuracy of 0.2μm/s with relative standard error <0.1. The required number of samples is reduced by 12 orders compared to conventional method. The predicted thermolubric behavior of water sliding on a self-assembled surface is directly validated by experiment under the same velocity. This theory only assumes the system is initially in thermal equilibrium, then driven from that equilibrium by an external perturbation. It could serve as a general approach for extracting the accurate estimate of dynamical quantities from large fluctuations to provide insights on atomic level under experimental conditions, and benefit the studies on mass transport through (biological) nanochannels and fluid film lubrication of nanometer thickness.
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Affiliation(s)
- Zhi Xu
- Department of Mechanical Engineering, State Key Laboratory of Tribology in Advanced Equipment (SKLT), Tsinghua University, Beijing 100084, China and Center for Nano and Micro Mechanics, Tsinghua University, Beijing 100084, China
| | - Han Li
- Department of Mechanical Engineering, State Key Laboratory of Tribology in Advanced Equipment (SKLT), Tsinghua University, Beijing 100084, China and Center for Nano and Micro Mechanics, Tsinghua University, Beijing 100084, China
| | - Ming Ma
- Department of Mechanical Engineering, State Key Laboratory of Tribology in Advanced Equipment (SKLT), Tsinghua University, Beijing 100084, China and Center for Nano and Micro Mechanics, Tsinghua University, Beijing 100084, China
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10
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Kobayashi Y, Arai N, Yasuoka K. Correlation between ordering and shear thinning in confined OMCTS liquids. J Chem Phys 2022; 157:114506. [DOI: 10.1063/5.0099473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Despite the extensive research that has been conducted for decades on the behavior of confined liquids, detailed knowledge of this phenomenon, particularly in the mixed/boundary lubrication regime, remains limited. This can be attributed to several factors including the difficulty of direct experimental observations of the behavior of lubricant molecules under non-equilibrium conditions, the high computational cost of molecular simulations to reach steady state, and the low signal-to-noise ratio at extremely low shear rates corresponding to actual operating conditions. To this end, we studied the correlation between the structure formation and shear viscosity of octamethylcyclotetrasiloxane confined between two mica surfaces in a mixed/boundary lubrication regime. Three different surface separations corresponding to two-, three-, and five-layered structures were considered to analyze the effect of confinement. The orientational distributions with one specific peak for n=2 and two distributions, including a parallel orientation with the surface normal for n>2, were observed at rest. The confined liquids exhibited a distinct shear-thinning behavior independent of surface separations for a relatively low shear rate, \dot{\gamma}<10^{8} s^{-1}. However, the shear viscosities at \dot{\gamma}<10^{8} s^{-1} depended on the number of layered structures. Newtonian behavior was observed with a further increase in the shear rate. Furthermore, we found a strong correlation between the degree of molecular orientation and the shear viscosity of the confined liquids. The magnitude of the shear viscosity of the confined liquids can primarily be determined by the degree of molecular orientation, and shear-thinning originates from the vanishing of specific orientational distributions with increasing shear rate.
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Affiliation(s)
- Yusei Kobayashi
- Mechanical Engineering, Keio University Faculty of Science and Technology Department of Mechanical Engineering, Japan
| | - Noriyoshi Arai
- Keio University Faculty of Science and Technology Department of Mechanical Engineering, Japan
| | - Kenji Yasuoka
- Mechanical Engineering, Keio University - Yagami Campus, Japan
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11
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Du A, Li H, Chen X, Han Y, Zhu Z, Chu C. Recent Research Progress of Silicon‐Based Anode Materials for Lithium‐Ion Batteries. ChemistrySelect 2022. [DOI: 10.1002/slct.202201269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Aimin Du
- School of Automotive Studies Tongji University Shanghai 201804 P.R.China
| | - Hang Li
- School of Automotive Studies Tongji University Shanghai 201804 P.R.China
| | - Xinwen Chen
- School of Automotive Studies Tongji University Shanghai 201804 P.R.China
| | - Yeyang Han
- School of Automotive Studies Tongji University Shanghai 201804 P.R.China
| | - Zhongpan Zhu
- School of Automotive Studies Tongji University Shanghai 201804 P.R.China
- School of Electronic and Information Engineering Tongji University Shanghai 201804 P.R.China
| | - Chuanchuan Chu
- School of Automotive Studies Tongji University Shanghai 201804 P.R.China
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12
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Gasparotto P, Fitzner M, Cox SJ, Sosso GC, Michaelides A. How do interfaces alter the dynamics of supercooled water? NANOSCALE 2022; 14:4254-4262. [PMID: 35244128 DOI: 10.1039/d2nr00387b] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The structure of liquid water in the proximity of an interface can deviate significantly from that of bulk water, with surface-induced structural perturbations typically converging to bulk values at about ∼1 nm from the interface. While these structural changes are well established it is, in contrast, less clear how an interface perturbs the dynamics of water molecules within the liquid. Here, through an extensive set of molecular dynamics simulations of supercooled bulk and interfacial water films and nano-droplets, we observe the formation of persistent, spatially extended dynamical domains in which the average mobility varies as a function of the distance from the interface. This is in stark contrast with the dynamical heterogeneity observed in bulk water, where these domains average out spatially over time. We also find that the dynamical response of water to an interface depends critically on the nature of the interface and on the choice of interface definition. Overall these results reveal a richness in the dynamics of interfacial water that opens up the prospect of tuning the dynamical response of water through specific modifications of the interface structure or confining material.
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Affiliation(s)
- Piero Gasparotto
- Scientific Computing Division, Paul Scherrer Institute, Villigen 5232, Switzerland.
| | - Martin Fitzner
- Thomas Young Centre, London Centre for Nanotechnology and Department of Physics and Astronomy, University College London, London WC1E 6BT, UK
| | - Stephen James Cox
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.
| | - Gabriele Cesare Sosso
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
| | - Angelos Michaelides
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.
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13
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Ebrahimi M, Foroutan M. High-Performance Biomimetic Water Channel: The Constructive Interplay of Interaction Parameters and Hydrophilic Doping Levels. J Phys Chem B 2021; 125:11566-11581. [PMID: 34615355 DOI: 10.1021/acs.jpcb.1c04507] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
In this study, we introduce a superfast biomimetic water channel mimicking the hydrophobicity scales of the Aquaporin (AQP) pore lining. Molecular dynamics simulation is used to scrutinize the impact of hydrophilic doping level in the nanotube and the water-wall interaction strength on water permeability. In the designed biomimetic channel, the constructive interplay of Lennard-Jones (LJ) ε parameters and hydrophilic doping levels increased the possibility of ultrafast water transport. Moreover, a unique set of LJ parameters is discovered for each biomimetic channel with different hydrophilic doping levels, enhancing water permeation. Inside high-performance biomimetic channels, water distribution surprisingly implies a varying pore geometry that narrows down in the middle, mimicking the pattern obtained from GplF pore analysis, evoking the narrow pore induced by the aromatic/arginine selectivity filter. This exciting accordance occurred as a result of tailoring specific hydrophilic arrays within the hydrophobic channel backbone by mimicking the AQP pore interior. The main takeaway of hydrophilic doping arrays implanted within the hydrophobic nanotube is to break the large barrier in the water-wall vdW energy profile into multiple reduced ones to increase water conduction. Consequently, the "water jumping" phenomenon in the middle of the biomimetic channel occurs under specific circumstances. The biomimetic channel with the highest value of water permeability of about 13.67 ± 0.66 × 10-13 cm3·s-1 exhibits the best mechanism for artificial water channels (AWCs), serving superfast water transport considering the low entrance barrier and weak water-wall interaction.
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Affiliation(s)
- Mina Ebrahimi
- Department of Physical Chemistry, School of Chemistry, College of Science, University of Tehran, Tehran 1417935840, Iran
| | - Masumeh Foroutan
- Department of Physical Chemistry, School of Chemistry, College of Science, University of Tehran, Tehran 1417935840, Iran
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14
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Di Giorgio C, Blundo E, Pettinari G, Felici M, Polimeni A, Bobba F. Exceptional Elasticity of Microscale Constrained MoS 2 Domes. ACS APPLIED MATERIALS & INTERFACES 2021; 13:48228-48238. [PMID: 34592817 PMCID: PMC8517950 DOI: 10.1021/acsami.1c13293] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 09/21/2021] [Indexed: 05/31/2023]
Abstract
The outstanding mechanical performances of two-dimensional (2D) materials make them appealing for the emerging fields of flextronics and straintronics. However, their manufacturing and integration in 2D crystal-based devices rely on a thorough knowledge of their hardness, elasticity, and interface mechanics. Here, we investigate the elasticity of highly strained monolayer-thick MoS2 membranes, in the shape of micrometer-sized domes, by atomic force microscopy (AFM)-based nanoindentation experiments. A dome's crushing procedure is performed to induce a local re-adhesion of the dome's membrane to the bulk substrate under the AFM tip's load. It is worth noting that no breakage, damage, or variation in size and shape are recorded in 95% of the crushed domes upon unloading. Furthermore, such a procedure paves the way to address quantitatively the extent of the van der Waals interlayer interaction and adhesion of MoS2 by studying pull-in instabilities and hysteresis of the loading-unloading cycles. The fundamental role and advantage of using a superimposed dome's constraint are also discussed.
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Affiliation(s)
- Cinzia Di Giorgio
- Department
of Physics E.R. Caianiello, University of
Salerno, 84084 Fisciano, Italy
- INFN,
Sezione di Napoli, Gruppo Collegato di Salerno, Complesso Universitario di Monte S. Angelo, 80126 Napoli, Italy
| | - Elena Blundo
- Physics
Department, Sapienza University of Rome, 00185 Rome, Italy
| | - Giorgio Pettinari
- Institute
for Photonics and Nanotechnologies (CNR-IFN), National Research Council, 00156 Rome, Italy
| | - Marco Felici
- Physics
Department, Sapienza University of Rome, 00185 Rome, Italy
| | - Antonio Polimeni
- Physics
Department, Sapienza University of Rome, 00185 Rome, Italy
| | - Fabrizio Bobba
- Department
of Physics E.R. Caianiello, University of
Salerno, 84084 Fisciano, Italy
- INFN,
Sezione di Napoli, Gruppo Collegato di Salerno, Complesso Universitario di Monte S. Angelo, 80126 Napoli, Italy
- CNR-SPIN, 84084 Fisciano, SA, Italy
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15
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Winarto, Yamamoto E, Yasuoka K. Water molecules in CNT-Si 3N 4 membrane: Properties and the separation effect for water-alcohol solution. J Chem Phys 2021; 155:104701. [PMID: 34525818 DOI: 10.1063/5.0055027] [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
Water confined in carbon nanotubes (CNTs) has been intensively studied because of its unique properties and potential for various applications and is often embedded in silicon nitride (Si3N4) membranes. However, the understanding of the influence of Si3N4 on the properties of water in CNTs lacks clarity. In this study, we performed molecular dynamics simulations to investigate the effect of the Si3N4 membrane on water molecules inside CNTs. The internal electric field generated in the CNTs by the point charges of the Si3N4 membrane changes the structure and dynamical properties of water in the nanotubes, causing it to attain a disordered structure. The Si3N4 membrane decreases the diffusivity of water in the CNTs; this is because the Coulomb potential energy (i.e., electrostatic interaction) of water decreases owing to the presence of Si3N4, whereas the Lennard-Jones potential energy (i.e., van der Waals interaction) does not change significantly. Furthermore, electrostatic interactions make the water structure more stable in the CNTs. As a result, the Si3N4 membrane enhances the separation effect of the water-methanol mixture with CNTs in the presence of an external electric field. Furthermore, the threshold of the external electric field strength to induce water-methanol separation with CNTs is reduced owing to the presence of a silicon nitride membrane.
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Affiliation(s)
- Winarto
- Department of Mechanical Engineering, Faculty of Engineering, Brawijaya University, Jl. MT Haryono 167, Malang 65145, Indonesia
| | - Eiji Yamamoto
- Department of System Design Engineering, Keio University, 3-14-1, Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
| | - Kenji Yasuoka
- Department of Mechanical Engineering, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
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16
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Chen Z, Yang J, Ma C, Zhou K, Jiao S. Continuous Water Filling in a Graphene Nanochannel: A Molecular Dynamics Study. J Phys Chem B 2021; 125:9824-9833. [PMID: 34424717 DOI: 10.1021/acs.jpcb.1c05658] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Low dimensional materials especially carbon materials hold high promise in the fields of water purification, mineral separation, energy harvesting/conversion, and so on. The fluidic devices fabricated by direct synthesis, lithography, or self-assembly of low dimensional materials provide opportunities for exploring the novel properties and applications of nanoconfined transport. Here, continuous filling of water and acetone molecules into a graphene nanochannel is investigated. A stairlike nonlinear dependence of the number of filling water molecules on interlayer distance d is found when d < 1 nm due to the existence of out-plane layered and in-plane ordered monolayer structure, while near-linear dependence is found for acetone because of the freely rotating configurations along with varying d during the filling process. The entropy, potential energy, and free energy of the confined system during the continuous filling are analyzed to understand the structural evolution of water. The energy-costs are discussed depending on the structure evolution of water during the filling, which is crucial to understanding the swelling and capillary condensation widely existing in the angstrom/nanometer-scale separation membranes.
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Affiliation(s)
- Zhe Chen
- Shanghai Key Laboratory of Mechanics in Energy Engineering, Shanghai Institute of Applied Mathematics and Mechanics, School of Mechanics and Engineering Science, Shanghai University, Yanchang Road 149, Shanghai 200444, China
| | - Jianwen Yang
- Department of Physics, Shanghai Normal University, Guilin Road 100, Shanghai 200234, China
| | - Chengpeng Ma
- Shanghai Key Laboratory of Mechanics in Energy Engineering, Shanghai Institute of Applied Mathematics and Mechanics, School of Mechanics and Engineering Science, Shanghai University, Yanchang Road 149, Shanghai 200444, China
| | - Ke Zhou
- State Key Laboratory for Strength and Vibration of Mechanical Structures, Laboratory for Multiscale Mechanics and Medical Science, School of Aerospace Engineering, Xi'an Jiaotong University, Xi'an 710049, China
| | - Shuping Jiao
- Shanghai Key Laboratory of Mechanics in Energy Engineering, Shanghai Institute of Applied Mathematics and Mechanics, School of Mechanics and Engineering Science, Shanghai University, Yanchang Road 149, Shanghai 200444, China
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17
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Hou Y, Dai Z, Zhang S, Feng S, Wang G, Liu L, Xu Z, Li Q, Zhang Z. Elastocapillary cleaning of twisted bilayer graphene interfaces. Nat Commun 2021; 12:5069. [PMID: 34417453 PMCID: PMC8379234 DOI: 10.1038/s41467-021-25302-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 07/21/2021] [Indexed: 11/18/2022] Open
Abstract
Although layered van der Waals (vdW) materials involve vast interface areas that are often subject to contamination, vdW interactions between layers may squeeze interfacial contaminants into nanopockets. More intriguingly, those nanopockets could spontaneously coalesce into larger ones, which are easier to be squeezed out the atomic channels. Such unusual phenomena have been thought of as an Ostwald ripening process that is driven by the capillarity of the confined liquid. The underlying mechanism, however, is unclear as the crucial role played by the sheet’s elasticity has not been previously appreciated. Here, we demonstrate the coalescence of separated nanopockets and propose a cleaning mechanism in which both elastic and capillary forces are at play. We elucidate this mechanism in terms of control of the nanopocket morphology and the coalescence of nanopockets via a mechanical stretch. Besides, we demonstrate that bilayer graphene interfaces excel in self-renewal phenomena. Here, the authors investigate the long-range interaction and coalescence mechanism of water and ethanol nanopockets encapsulated in twisted bilayer graphene, showing the complete recovery of moiré patterns after the motion of the contaminants.
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Affiliation(s)
- Yuan Hou
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, P.R. China.,CAS Key Laboratory of Mechanical Behavior and Design of Materials, Department of Modern Mechanics, University of Science and Technology of China, Hefei, P. R. China
| | - Zhaohe Dai
- Department of Aerospace Engineering and Engineering Mechanics, The University of Texas at Austin, Austin, TX, USA
| | - Shuai Zhang
- Applied Mechanics Laboratory, Department of Engineering Mechanics, and Center for Nano and Micro Mechanics, Tsinghua University, Beijing, P. R. China.,State Key Laboratory of Tribology, Tsinghua University, Beijing, P. R. China
| | - Shizhe Feng
- Applied Mechanics Laboratory, Department of Engineering Mechanics, and Center for Nano and Micro Mechanics, Tsinghua University, Beijing, P. R. China
| | - Guorui Wang
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, P.R. China.,CAS Key Laboratory of Mechanical Behavior and Design of Materials, Department of Modern Mechanics, University of Science and Technology of China, Hefei, P. R. China
| | - Luqi Liu
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, P.R. China.
| | - Zhiping Xu
- Applied Mechanics Laboratory, Department of Engineering Mechanics, and Center for Nano and Micro Mechanics, Tsinghua University, Beijing, P. R. China.
| | - Qunyang Li
- Applied Mechanics Laboratory, Department of Engineering Mechanics, and Center for Nano and Micro Mechanics, Tsinghua University, Beijing, P. R. China. .,State Key Laboratory of Tribology, Tsinghua University, Beijing, P. R. China.
| | - Zhong Zhang
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, P.R. China. .,CAS Key Laboratory of Mechanical Behavior and Design of Materials, Department of Modern Mechanics, University of Science and Technology of China, Hefei, P. R. China.
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18
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Robin P, Kavokine N, Bocquet L. Modeling of emergent memory and voltage spiking in ionic transport through angstrom-scale slits. Science 2021; 373:687-691. [PMID: 34353953 DOI: 10.1126/science.abf7923] [Citation(s) in RCA: 60] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 06/11/2021] [Indexed: 01/10/2023]
Abstract
Recent advances in nanofluidics have enabled the confinement of water down to a single molecular layer. Such monolayer electrolytes show promise in achieving bioinspired functionalities through molecular control of ion transport. However, the understanding of ion dynamics in these systems is still scarce. Here, we develop an analytical theory, backed up by molecular dynamics simulations, that predicts strongly nonlinear effects in ion transport across quasi-two-dimensional slits. We show that under an electric field, ions assemble into elongated clusters, whose slow dynamics result in hysteretic conduction. This phenomenon, known as the memristor effect, can be harnessed to build an elementary neuron. As a proof of concept, we carry out molecular simulations of two nanofluidic slits that reproduce the Hodgkin-Huxley model and observe spontaneous emission of voltage spikes characteristic of neuromorphic activity.
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Affiliation(s)
- Paul Robin
- Laboratoire de Physique de l'École Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, F-75005 Paris, France
| | - Nikita Kavokine
- Laboratoire de Physique de l'École Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, F-75005 Paris, France
| | - Lydéric Bocquet
- Laboratoire de Physique de l'École Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, F-75005 Paris, France.
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19
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Muñoz-Santiburcio D, Marx D. Confinement-Controlled Aqueous Chemistry within Nanometric Slit Pores. Chem Rev 2021; 121:6293-6320. [PMID: 34006106 DOI: 10.1021/acs.chemrev.0c01292] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In this Focus Review, we put the spotlight on very recent insights into the fascinating world of wet chemistry in the realm offered by nanoconfinement of water in mechanically rather rigid and chemically inert planar slit pores wherein only monolayer and bilayer water lamellae can be hosted. We review the effect of confinement on different aspects such as hydrogen bonding, ion diffusion, and charge defect migration of H+(aq) and OH-(aq) in nanoconfined water depending on slit pore width. A particular focus is put on the strongly modulated local dielectric properties as quantified in terms of anisotropic polarization fluctuations across such extremely confined water films and their putative effects on chemical reactions therein. The stunning findings disclosed only recently extend wet chemistry in particular and solvation science in general toward extreme molecular confinement conditions.
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Affiliation(s)
- Daniel Muñoz-Santiburcio
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany.,CIC nanoGUNE BRTA, Tolosa Hiribidea 76, 20018 San Sebastián, Spain
| | - Dominik Marx
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
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20
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Bampoulis P. Temperature induced dynamics of water confined between graphene and MoS 2. J Chem Phys 2021; 154:134705. [PMID: 33832247 DOI: 10.1063/5.0044123] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Water trapped between MoS2 and graphene assumes a form of ice composed of two planar hexagonal layers with a non-tetrahedral geometry. Additional water does not wet these ice layers but forms three-dimensional droplets. Here, we have investigated the temperature induced dewetting dynamics of the confined ice and water droplets. The ice crystals gradually decrease in size with increasing substrate temperature and completely vanish at about 80 °C. Further heating to 100 °C induces changes in water droplet density, size, and shape through droplet coalescence and dissolution. However, even prolonged annealing at 100 °C does not completely dry the interface. The dewetting dynamics are controlled by the graphene cover. Thicker graphene flakes allow faster water diffusion as a consequence of the reduction of graphene's conformity along the ice crystal's edges, which leaves enough space for water molecules to diffuse along the ice edges and evaporate to the environment through defects in the graphene cover.
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Affiliation(s)
- P Bampoulis
- Physics of Interfaces and Nanomaterials, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500AE Enschede, The Netherlands and II. Physikalisches Institut, Universität zu Köln, Cologne D-50937, Germany
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21
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Sanchez DA, Dai Z, Lu N. 2D Material Bubbles: Fabrication, Characterization, and Applications. TRENDS IN CHEMISTRY 2021. [DOI: 10.1016/j.trechm.2020.12.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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22
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Yan Y, Ding S, Wu X, Zhu J, Feng D, Yang X, Li F. Tuning the physical properties of ultrathin transition-metal dichalcogenides via strain engineering. RSC Adv 2020; 10:39455-39467. [PMID: 35515419 PMCID: PMC9057462 DOI: 10.1039/d0ra07288e] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 10/13/2020] [Indexed: 01/05/2023] Open
Abstract
Transition-metal dichalcogenides (TMDs) have become one of the recent frontiers and focuses in two-dimensional (2D) materials fields thanks to their superior electronic, optical, and photoelectric properties. Triggered by the growing demand for developing nano-electronic devices, strain engineering of ultrathin TMDs has become a hot topic in the scientific community. In recent years, both theoretical and experimental research on the strain engineering of ultrathin TMDs have suggested new opportunities to achieve high-performance ultrathin TMDs based devices. However, recent reviews mainly focus on the experimental progress and the related theoretical research has long been ignored. In this review, we first outline the currently employed approaches for introducing strain in ultrathin TMDs, both their characteristics and advantages are explained in detail. Subsequently, the recent research progress in the modification of lattice and electronic structure, and physical properties of ultrathin TMDs under strain are systematically reviewed from both experimental and theoretical perspectives. Despite much work being done in this filed, reducing the distance of experimental progress from the theoretical prediction remains a great challenge in realizing wide applications of ultrathin TMDs in nano-electronic devices.
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Affiliation(s)
- Yalan Yan
- Institute for Interdisciplinary Biomass Functional Materials Studies, Jilin Engineering Normal University No. 3050 Kaixuan Road Changchun 130052 People's Republic of China
| | - Shuang Ding
- Institute for Interdisciplinary Biomass Functional Materials Studies, Jilin Engineering Normal University No. 3050 Kaixuan Road Changchun 130052 People's Republic of China
| | - Xiaonan Wu
- Department of Chemical Engineering, Chengde Petroleum College Chengde 067000 People's Republic of China
| | - Jian Zhu
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University No. 2699 Qianjin Street Changchun 130012 People's Republic of China
| | - Dengman Feng
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University No. 2699 Qianjin Street Changchun 130012 People's Republic of China
| | - Xiaodong Yang
- Institute for Interdisciplinary Biomass Functional Materials Studies, Jilin Engineering Normal University No. 3050 Kaixuan Road Changchun 130052 People's Republic of China
| | - Fangfei Li
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University No. 2699 Qianjin Street Changchun 130012 People's Republic of China
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23
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Tocci G, Bilichenko M, Joly L, Iannuzzi M. Ab initio nanofluidics: disentangling the role of the energy landscape and of density correlations on liquid/solid friction. NANOSCALE 2020; 12:10994-11000. [PMID: 32426791 DOI: 10.1039/d0nr02511a] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Despite relevance to water purification and renewable energy conversion membranes, the molecular mechanisms underlying water slip are poorly understood. We disentangle the static and dynamical origin of water slippage on graphene, hBN and MoS2 by means of large-scale ab initio molecular dynamics. Accounting for the role of the electronic structure of the interface is essential to determine that water slips five and eleven times faster on graphene compared to hBN and to MoS2, respectively. Intricate changes in the water energy landscape as well as in the density correlations of the fluid provide, respectively, the main static and dynamical origin of water slippage. Surprisingly, the timescales of the density correlations are the same on graphene and hBN, whereas they are longer on MoS2 and yield a 100% slowdown in the flow of water on this material. Our results pave the way for an in silico first principles design of materials with enhanced water slip, through the modification of properties connected not only to the structure, but also to the dynamics of the interface.
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Affiliation(s)
- Gabriele Tocci
- Department of Chemistry, Universität Zürich, 8057 Zürich, Switzerland.
| | - Maria Bilichenko
- Department of Chemistry, Universität Zürich, 8057 Zürich, Switzerland.
| | - Laurent Joly
- Univ Lyon, Univ Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, Villeurbanne, France and Institut Universitaire de France (IUF), France
| | - Marcella Iannuzzi
- Department of Chemistry, Universität Zürich, 8057 Zürich, Switzerland.
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24
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Li F, Korotkin IA, Karabasov SA. Rheology of Water Flows Confined between Multilayer Graphene Walls. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:5633-5646. [PMID: 32370511 DOI: 10.1021/acs.langmuir.0c01049] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Water confined by hydrophilic materials shows unique transport properties compared to bulk water, thereby offering new opportunities for the development of nanofluidic devices. Recent experimental and numerical studies showed that nanoconfined water undergoes liquid- to solid-phase-like transitions depending on the degree of confinement. In the case of water confined by graphene layers, the van der Waals forces are known to deform the graphene layers, whose bending leads to further nonuniform confinement effects. Despite the extensive studies of nanoconfined water under equilibrium conditions, the interplay between the confinement and rheological water properties, such as viscosity, slip length, and normal stress differences under shear flow conditions, is poorly understood. The current investigation uses a validated all-atom nonequilibrium molecular dynamics model to simultaneously analyze the continuum transport and atomistic structural properties of water in a slit between two moving graphene walls under Couette flow conditions. A range of different slit widths and velocity strain rates are considered. It is shown that under subnanometer confinement, water loses the rotational symmetry of a Newtonian fluid. Under such conditions, water transforms into ice, where the atomistic structure is completely insensitive to the applied shear force and behaves like a frozen slab sliding between the graphene walls. This leads to the shear viscosity increase, although it is not as dramatic as the normal force increase that contributes to the increased friction force reported in previous experimental studies. On the other end of the spectrum, for flows at large velocity strain rates in moderate to large slits between the graphene walls, water is in the liquid state and reveals shear thinning behavior. In this case, water exhibits a constant slip length on the wall, which is typical of liquids in the vicinity of hydrophobic surfaces.
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Affiliation(s)
- F Li
- The School of Engineering and Materials Science, Queen Mary University of London, Mile End Road, E1 4NS London, United Kingdom
| | - I A Korotkin
- The School of Engineering and Materials Science, Queen Mary University of London, Mile End Road, E1 4NS London, United Kingdom
- Mathematical Sciences, University of Southampton, University Road, SO17 1BJ Southampton, United Kingdom
| | - S A Karabasov
- The School of Engineering and Materials Science, Queen Mary University of London, Mile End Road, E1 4NS London, United Kingdom
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25
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Tendong E, Dasgupta TS, Chakrabarti J. Dynamics of water trapped in transition metal oxide-graphene nano-confinement. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:325101. [PMID: 32191936 DOI: 10.1088/1361-648x/ab814f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 03/19/2020] [Indexed: 06/10/2023]
Abstract
Motivated by practical implementation of transition-metal oxide-graphene heterostructures, we use all atom molecular dynamics simulations to study dynamics of water in a nano slit bounded by a transition metal oxide surface, namely, TiO2termination of SrTiO3, and graphene. The resultant asymmetric, strong confinement produces square ice-like crystallites of water pinned at TiO2surface and drives enhanced hydrophobicity of graphene via the proximity effect to the hydrophilic TiO2surface. This importantly brings in dynamic heterogeneity, both in translational and rotational degrees of freedom, due to coupling between the slow relaxing, strongly adsorbed water layer at the hydrophilic oxide surface, and faster relaxation of subsequent water layers. The heterogeneity is signalled in the ruggedness of the effective free energy landscapes. We discuss possible implications of our findings in drug delivery.
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Affiliation(s)
- E Tendong
- Department of Condensed Matter Physics and Material Sciences & Department of Chemical Biological and Macromoleculer Sciences, S N Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata - 700106, India
| | - T Saha Dasgupta
- Department of Condensed Matter Physics and Material Sciences & Department of Chemical Biological and Macromoleculer Sciences, S N Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata - 700106, India
| | - J Chakrabarti
- Department of Condensed Matter Physics and Material Sciences,Thematic Unit of Excellence for Material Science & Technology Research Centre, S N Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata - 700106, India
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26
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Chen M, Zhou H, Zhu R, Lu X, He H. Closest-Packing Water Monolayer Stably Intercalated in Phyllosilicate Minerals under High Pressure. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:618-627. [PMID: 31886678 DOI: 10.1021/acs.langmuir.9b03394] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The directional hydrogen-bond (HB) network and nondirectional van der Waals (vdW) interactions make up the specificity of water. Directional HBs could construct an ice-like monolayer in hydrophobic confinement even in the ambient regime. Here, we report a water monolayer dominated by vdW interactions confined in a phyllosilicate interlayer under high pressure. Surprisingly, it was in a thermodynamically stable state coupled with bulk water at the same pressure (P) and temperature (T), as revealed by the thermodynamic integration approach on the basis of molecular dynamics (MD) simulations. Both classical and ab initio MD simulations showed water O atoms were stably trapped and exhibited an ordered hexagonal closest-packing arrangement, but OH bonds of water reoriented frequently and exhibited a specific two-stage reorientation relaxation. Strikingly, hydration in the interlayer under high pressure had no relevance with surface hydrophilicity rationalized by the HB forming ability, which, however, determines wetting in the ambient regime. Intercalated water molecules were trapped by vdW interactions, which shaped the closest-packing arrangement and made hydration energetically available. The high pressure-volume term largely drives hydration, as it compensates the entropy penalty which is restricted by a relatively lower temperature. This vdW water monolayer should be ubiquitous in the high pressure but low-temperature regime.
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Affiliation(s)
- Meng Chen
- CAS Key Laboratory of Mineralogy and Metallogeny/Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Institutions of Earth Science , Chinese Academy of Sciences (CAS) , Guangzhou 510640 , China
| | - Huijun Zhou
- CAS Key Laboratory of Mineralogy and Metallogeny/Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Institutions of Earth Science , Chinese Academy of Sciences (CAS) , Guangzhou 510640 , China
- University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Runliang Zhu
- CAS Key Laboratory of Mineralogy and Metallogeny/Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Institutions of Earth Science , Chinese Academy of Sciences (CAS) , Guangzhou 510640 , China
| | - Xiancai Lu
- State Key Laboratory for Mineral Deposits Research, School of Earth Sciences and Engineering , Nanjing University , Nanjing 210093 , China
| | - Hongping He
- CAS Key Laboratory of Mineralogy and Metallogeny/Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Institutions of Earth Science , Chinese Academy of Sciences (CAS) , Guangzhou 510640 , China
- University of Chinese Academy of Sciences , Beijing 100049 , China
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27
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Díez Fernández A, Charchar P, Cherstvy AG, Metzler R, Finnis MW. The diffusion of doxorubicin drug molecules in silica nanoslits is non-Gaussian, intermittent and anticorrelated. Phys Chem Chem Phys 2020; 22:27955-27965. [DOI: 10.1039/d0cp03849k] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The motion of the confined doxorubicin drug molecule exhibits an interesting combination of anomalous diffusion features.
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Affiliation(s)
- Amanda Díez Fernández
- Department of Physics and Department of Materials
- Imperial College London
- London SW7 2AZ
- UK
| | | | - Andrey G. Cherstvy
- Institute for Physics & Astronomy
- University of Potsdam
- 14476 Potsdam-Golm
- Germany
| | - Ralf Metzler
- Institute for Physics & Astronomy
- University of Potsdam
- 14476 Potsdam-Golm
- Germany
| | - Michael W. Finnis
- Department of Physics and Department of Materials
- Imperial College London
- London SW7 2AZ
- UK
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28
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Abstract
Water diffusion in nanopores has attracted considerable attention in the past decades. Recently the coupling between the vibration of pore walls and movement of confined water has been recognized to largely enhance diffusion. However, its impact on water diffusion in graphene oxide membranes remains to be discussed. Here we explore how water diffusion couples with the thermal fluctuation of graphene nanochannels by molecular dynamics simulations. Our finding demonstrates an approximately linear dependence of diffusion enhancement on temperature; i.e., the wiggling nanopore enhances diffusion at low temperature and inhibits diffusion at high temperature. This mechanism is further extended to be applicable for another two typical layered materials, hBN and MoS2. These results offer opportunities to tune surface diffusion by thermal operation or mechanical activation, advancing the application of two-dimensional materials in membrane separations.
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29
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Dai Z, Liu L, Zhang Z. Strain Engineering of 2D Materials: Issues and Opportunities at the Interface. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1805417. [PMID: 30650204 DOI: 10.1002/adma.201805417] [Citation(s) in RCA: 205] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2018] [Revised: 10/04/2018] [Indexed: 05/23/2023]
Abstract
Triggered by the growing needs of developing semiconductor devices at ever-decreasing scales, strain engineering of 2D materials has recently seen a surge of interest. The goal of this principle is to exploit mechanical strain to tune the electronic and photonic performance of 2D materials and to ultimately achieve high-performance 2D-material-based devices. Although strain engineering has been well studied for traditional semiconductor materials and is now routinely used in their manufacturing, recent experiments on strain engineering of 2D materials have shown new opportunities for fundamental physics and exciting applications, along with new challenges, due to the atomic nature of 2D materials. Here, recent advances in the application of mechanical strain into 2D materials are reviewed. These developments are categorized by the deformation modes of the 2D material-substrate system: in-plane mode and out-of-plane mode. Recent state-of-the-art characterization of the interface mechanics for these 2D material-substrate systems is also summarized. These advances highlight how the strain or strain-coupled applications of 2D materials rely on the interfacial properties, essentially shear and adhesion, and finally offer direct guidelines for deterministic design of mechanical strains into 2D materials for ultrathin semiconductor applications.
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Affiliation(s)
- Zhaohe Dai
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, P. R. China
| | - Luqi Liu
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, P. R. China
| | - Zhong Zhang
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, P. R. China
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30
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Brandenburg JG, Zen A, Alfè D, Michaelides A. Interaction between water and carbon nanostructures: How good are current density functional approximations? J Chem Phys 2019; 151:164702. [DOI: 10.1063/1.5121370] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Affiliation(s)
- Jan Gerit Brandenburg
- Interdisciplinary Center for Scientific Computing, University of Heidelberg, Im Neuenheimer Feld 205A, 69120 Heidelberg, Germany
| | - Andrea Zen
- Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT, United Kingdom
- Thomas Young Centre and London Centre for Nanotechnology, 17-19 Gordon Street, London WC1H 0AH, United Kingdom
| | - Dario Alfè
- Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT, United Kingdom
- Thomas Young Centre and London Centre for Nanotechnology, 17-19 Gordon Street, London WC1H 0AH, United Kingdom
- Dipartimento di Fisica Ettore Pancini, Università di Napoli Federico II, Monte S. Angelo, I-80126 Napoli, Italy
| | - Angelos Michaelides
- Thomas Young Centre and London Centre for Nanotechnology, 17-19 Gordon Street, London WC1H 0AH, United Kingdom
- Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom
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Ho TA, Criscenti LJ, Greathouse JA. Revealing Transition States during the Hydration of Clay Minerals. J Phys Chem Lett 2019; 10:3704-3709. [PMID: 31244275 DOI: 10.1021/acs.jpclett.9b01565] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
A molecular-scale understanding of the transition between hydration states in clay minerals remains a challenging problem because of the very fast stepwise swelling process observed from X-ray diffraction (XRD) experiments. XRD profile modeling assumes the coexistence of multiple hydration states in a clay sample to fit the experimental XRD pattern obtained under humid conditions. While XRD profile modeling provides a macroscopic understanding of the heterogeneous hydration structure of clay minerals, a microscopic model of the transition between hydration states is still missing. Here, for the first time, we use molecular dynamics simulation to investigate the transition states between a dry interlayer, one-layer hydrate, and two-layer hydrate. We find that the hydrogen bonds that form across the interlayer at the clay particle edge make an important contribution to the energy barrier to interlayer hydration, especially for initial hydration.
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Affiliation(s)
- Tuan A Ho
- Geochemistry Department , Sandia National Laboratories , Albuquerque , New Mexico 87185 , United States
| | - Louise J Criscenti
- Geochemistry Department , Sandia National Laboratories , Albuquerque , New Mexico 87185 , United States
| | - Jeffery A Greathouse
- Geochemistry Department , Sandia National Laboratories , Albuquerque , New Mexico 87185 , United States
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32
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Abstract
Liquid-phase exfoliation (LPE) is the best-known method for the synthesis of two-dimensional (2D) nanosheets. Compared to enthalpy, entropy is hardly considered to be a factor in choosing energy-efficient solvents and has not even been verified to be negligible. In this Letter, we explore the entropy contribution in LPE by performing molecular dynamics (MD) simulation of the structural flexibility effect in graphene, hexagonal boron nitride (hBN), and molybdenum disulfide (MoS2). Our results show that surface vibration favors the exfoliation of graphene and hBN and destabilizes the reaggregation of nanosheets in water at 300 K, whereas the opposite is found for MoS2. The entropy change is found to be 41%, 48%, and 4% of the enthalpy gain for graphene, hBN, and MoS2 in LPE, respectively, and 64%, 32%, and 56% in reaggregation, which amounts to a step advancement for solvent screening in LPE of 2D materials.
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Brandenburg JG, Zen A, Fitzner M, Ramberger B, Kresse G, Tsatsoulis T, Grüneis A, Michaelides A, Alfè D. Physisorption of Water on Graphene: Subchemical Accuracy from Many-Body Electronic Structure Methods. J Phys Chem Lett 2019; 10:358-368. [PMID: 30615460 DOI: 10.1021/acs.jpclett.8b03679] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Wet carbon interfaces are ubiquitous in the natural world and exhibit anomalous properties, which could be exploited by emerging technologies. However, progress is limited by lack of understanding at the molecular level. Remarkably, even for the most fundamental system (a single water molecule interacting with graphene), there is no consensus on the nature of the interaction. We tackle this by performing an extensive set of complementary state-of-the-art computer simulations on some of the world's largest supercomputers. From this effort a consensus on the water-graphene interaction strength has been obtained. Our results have significant impact for the physical understanding, as they indicate that the interaction is weaker than predicted previously. They also pave the way for more accurate and reliable studies of liquid water at carbon interfaces.
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Affiliation(s)
- Jan Gerit Brandenburg
- Department of Physics and Astronomy , University College London , Gower Street , London WC1E 6BT , United Kingdom
- Thomas Young Centre and London Centre for Nanotechnology , 17-19 Gordon Street , London WC1H 0AH , United Kingdom
| | - Andrea Zen
- Department of Physics and Astronomy , University College London , Gower Street , London WC1E 6BT , United Kingdom
- Thomas Young Centre and London Centre for Nanotechnology , 17-19 Gordon Street , London WC1H 0AH , United Kingdom
| | - Martin Fitzner
- Department of Physics and Astronomy , University College London , Gower Street , London WC1E 6BT , United Kingdom
- Thomas Young Centre and London Centre for Nanotechnology , 17-19 Gordon Street , London WC1H 0AH , United Kingdom
| | - Benjamin Ramberger
- University of Vienna , Faculty of Physics and Center for Computational Materials Sciences , Sensengasse 8/12 , 1090 Wien , Austria
| | - Georg Kresse
- University of Vienna , Faculty of Physics and Center for Computational Materials Sciences , Sensengasse 8/12 , 1090 Wien , Austria
| | - Theodoros Tsatsoulis
- Institute for Theoretical Physics , Vienna University of Technology , Wiedner Hauptstrasse 8-10 , 1040 Vienna , Austria
- Max Planck Institute for Solid State Research , Heisenbergstrasse 1 , 70569 Stuttgart , Germany
| | - Andreas Grüneis
- Institute for Theoretical Physics , Vienna University of Technology , Wiedner Hauptstrasse 8-10 , 1040 Vienna , Austria
- Max Planck Institute for Solid State Research , Heisenbergstrasse 1 , 70569 Stuttgart , Germany
| | - Angelos Michaelides
- Department of Physics and Astronomy , University College London , Gower Street , London WC1E 6BT , United Kingdom
- Thomas Young Centre and London Centre for Nanotechnology , 17-19 Gordon Street , London WC1H 0AH , United Kingdom
| | - Dario Alfè
- Thomas Young Centre and London Centre for Nanotechnology , 17-19 Gordon Street , London WC1H 0AH , United Kingdom
- Department of Earth Sciences , University College London , Gower Street , London WC1E 6BT , United Kingdom
- Dipartimento di Fisica Ettore Pancini , Università di Napoli Federico II , Monte S. Angelo, I-80126 Napoli , Italy
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Ruiz-Barragan S, Muñoz-Santiburcio D, Marx D. Nanoconfined Water within Graphene Slit Pores Adopts Distinct Confinement-Dependent Regimes. J Phys Chem Lett 2019; 10:329-334. [PMID: 30571135 DOI: 10.1021/acs.jpclett.8b03530] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
In view of the increasing importance of nanoconfined aqueous solutions for various technological applications, it has become necessary to understand how strong confinement affects the properties of water at the level of molecular and even electronic structure. By performing extensive ab initio simulations of two-dimensionally nanoconfined water lamellae between graphene sheets subject to different interlayer spacings, we find new regimes at interlayer distances of 10 Å and less where water can be described neither to behave like interfacial water nor to be bulklike at the level of its H-bonding characteristics and electronic structure properties. It is expected that this finding will offer new opportunities to tune both diffusive and reactive processes taking place in aqueous environments that are strongly confined by chemically inert hard walls.
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Affiliation(s)
- Sergi Ruiz-Barragan
- Lehrstuhl für Theoretische Chemie , Ruhr-Universität Bochum , 44780 Bochum , Germany
| | - Daniel Muñoz-Santiburcio
- Lehrstuhl für Theoretische Chemie , Ruhr-Universität Bochum , 44780 Bochum , Germany
- CIC nanoGUNE , Tolosa Hiribidea 76 , E-20018 San Sebastián , Spain
| | - Dominik Marx
- Lehrstuhl für Theoretische Chemie , Ruhr-Universität Bochum , 44780 Bochum , Germany
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Nanda R, Bowers GM, Loganathan N, Burton SD, Kirkpatrick RJ. Temperature dependent structure and dynamics in smectite interlayers: 23Na MAS NMR spectroscopy of Na-hectorite. RSC Adv 2019; 9:12755-12765. [PMID: 35515846 PMCID: PMC9063695 DOI: 10.1039/c9ra01056d] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Accepted: 04/11/2019] [Indexed: 11/25/2022] Open
Abstract
23Na MAS NMR spectroscopy of the smectite mineral hectorite acquired at temperatures from −120 °C to 40 °C in combination with the results from computational molecular dynamics (MD) simulations show the presence of complex dynamical processes in the interlayer galleries that depend significantly on their hydration state. The results indicate that site exchange occurs within individual interlayers that contain coexisting 1 and 2 water layer hydrates in different places. We suggest that the observed dynamical averaging may be due to motion of water volumes comparable to the dripplons recently proposed to occur in hydrated graphene interlayers (Yoshida et al. Nat. Commun., 2018, 9, 1496). Such motion would cause rippling of the T-O-T structure of the clay layers at frequencies greater than ∼25 kHz. For samples exposed to 0% relative humidity (R.H.), the 23Na spectra show the presence of two Na+ sites (probably 6 and 9 coordinated by basal oxygen atoms) that do not undergo dynamical averaging at any temperature from −120 °C to 40 °C. For samples exposed to R.H.s from 29% to 100% the spectra show the presence of three hydrated Na+ sites that undergo dynamical averaging beginning at −60 °C. These sites have different numbers of H2O molecules coordinating the Na+, and diffusion calculations indicate that they probably occur within the same individual interlayer. The average hydration state of Na+ increases with increasing R.H. and water content of the clay. 23Na MAS NMR spectroscopy of the smectite mineral hectorite acquired at temperature from −120 °C to 40 °C shows the presence of complex dynamical processes in the interlayer galleries that depend significantly on their hydration state.![]()
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Affiliation(s)
- Raju Nanda
- Department of Chemistry
- Michigan State University
- East Lansing
- USA
- Department of Chemistry
| | - Geoffrey M. Bowers
- Department of Chemistry and Biochemistry
- St. Mary's College of Maryland
- St. Mary's City
- USA
| | | | - Sarah D. Burton
- William R. Wiley Environmental and Molecular Sciences Laboratory
- Pacific Northwest National Laboratory
- Richland
- USA
| | - R. James Kirkpatrick
- Department of Chemistry
- Michigan State University
- East Lansing
- USA
- Department of Earth and Environmental Sciences
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