Publications
389 results found
Kornyshev AA, Lee DJ, Wynveen A, 2017, Theory of phase segregation in DNA assemblies containing two different base pair sequence types, New Journal of Physics, Vol: 19, ISSN: 1367-2630
Spontaneous pairing ofhomologous DNAsequences –a challenging subject in molecular biophysics,often referred to as‘homology recognition’ –hasbeen observedin vitrofor several DNAsystemsa. One of these experiments involvedliquid crystalline quasi-columnar phases formed by a mixture of two kindsof oligomerof double stranded DNA. Both oligomer types wereof the same length and identical stoichiometric base-pair composition,but the base-pairs followed a different order. Phase segregation of the two DNA types was observedin the experiments, with the formation of boundariesbetween domainsrich inmolecules of one type (order) ofbase pair sequence. We formulate here a modified ‘X-Y model’for phase segregation in such assemblies, obtain approximate solutions of the model, compare analytical results toMonte Carlosimulations, and rationalize pastexperimental observations. This study,furthermore,reveals the factors that affect the degree of segregation. Such information could be usedin planning new versions of similarsegregationexperiments, neededfordeepeningour understanding offorces that might be involved, e.g., ingene-gene recognition.
David A, Fajardo OY, Kornyshev AA, et al., 2017, Electrotunable lubricity with ionic liquids: the influence of nanoscale roughness, Faraday Discuss, Vol: 199, Pages: 279-297, ISSN: 1359-6640
The properties of ionic liquids can be modified by applying an external electrostatic potential, providing a route to control their performance in nanolubrication applications. Most computational studies to date have focused on the investigation of smooth surfaces. Real surfaces are generally inhomogeneous and feature roughness of different length scales. We report here a study of the possible effects that surface roughness may have on electrotunable lubricity with ionic liquids, performed here by means of non-equilibrium molecular dynamics simulations. In order to advance our understanding of the interplay of friction and substrate structure we investigate coarse grained models of ionic liquids confined in model surfaces with nanometer roughness. The friction is shown to depend on the roughness of the substrate and the direction of shear. For the investigated systems, the friction coefficient is found to increase with roughness. These results are in contrast with previous studies, where roughness induced reduction of friction was reported, and they highlight the strong sensitivity of the friction process to the structure of the surfaces. The friction force features a maximum at a specific surface charge density. This behaviour is reminiscent of the one reported in ionic liquids confined by flat surfaces, showing the generality of this physical effect in confined ionic liquids. We find that an increase of the substrate-liquid dispersion interactions shifts the maximum to lower surface charges. This effect opens a route to control electrotunable friction phenomena by tuning both the electrostatic potential and the composition of the confining surfaces.
Goodwin ZAH, Feng G, Kornyshev AA, 2016, Mean-field theory of electrical double layer in ionic liquids with account of short-range correlations, Electrochimica Acta, Vol: 225, Pages: 190-197, ISSN: 0013-4686
We develop the theory of the electrical double layer in ionic liquids as proposed earlier by Kornyshev (2007). In the free energy function we keep the so called ‘short-range correlation terms’ which were omitted there. With some simplifying assumptions, we arrive at a modified expression for differential capacitance, which makes differential capacitance curves less sharply depending on electrode potential and having smaller values at extrema than in the previous theory. This brings the results closer to typical experimental observations, and makes it appealing to use this formalism for treatment of experimental data. Implications on Debye length and the extent of ion paring in ionic liquids are then briefly discussed.
Sikdar D, Bucher A, Zagar C, et al., 2016, Electrochemical plasmonic metamaterials: towards fast electro-tuneable reflecting nanoshutters, Faraday Discuss, Vol: 199, Pages: 585-602, ISSN: 1359-6640
Self-assembling arrays of metallic nanoparticles at liquid|liquid or liquid|solid interfaces could deliver new platforms for tuneable optical systems. Such systems can switch between very-high and very-low reflectance states upon assembly and disassembly of nanoparticles at the interface, respectively. This encourages creation of electro-variably reversible mirror/window nanoplasmonic devices. However, the response time of these systems is usually limited by the rate-of-diffusion of the nanoparticles in the liquid, towards the interface and back. A large time-constant implies slow switching of the system, challenging the practical viability of such a system. Here we introduce a smart alternative to overcome this issue. We propose obtaining fast switching via electrically-induced rotation of a two-dimensional array of metal nanocuboids tethered to an ITO substrate. By applying potential to the ITO electrode the orientation of nanocuboids can be altered, which results in conversion of a highly-reflective nanoparticle layer into a transparent layer (or vice versa) within sub-second timescales. A theoretical method is developed based on the quasi-static effective-medium approach to analyse the optical response of such arrays, which is verified against full-wave simulations. Further theoretical analysis and estimates based on the potential energy of the nanoparticles in the two orientations corroborate the idea that voltage-controlled switching between the two states of a nanoparticle assembly is a viable option.
Velleman L, Sikdar D, Turek V, et al., 2016, Tuneable 2D self-assembly of plasmonic nanoparticles at liquid | liquid interfaces, Nanoscale, Vol: 8, Pages: 19229-19241, ISSN: 2040-3372
Understanding the structure and assembly of nanoparticles at liquid | liquid interfaces is paramount to their integration into devices for sensing, catalysis, electronics and optics. However, many difficulties arise when attempting to resolve the structure of such interfacial assemblies. In this article we use a combination of X-ray diffraction and optical reflectance to determine the structural arrangement and plasmon coupling between 12.8 nm diameter gold nanoparticles assembled at a water | 1,2-dichloroethane interface. The liquid | liquid interface provides a molecularly flat and defect-correcting platform for nanoparticles to self-assemble. The amount of nanoparticles assembling at the interface can be controlled via the concentration of electrolyte within either the aqueous or organic phase. At higher electrolyte concentration more nanoparticles can settle at the liquid | liquid interface resulting in a decrease in nanoparticle spacing as observed from X-ray diffraction experiments. The coupling of plasmons between the nanoparticles as they come closer together is observed by a red-shift in the optical reflectance spectra. The optical reflectance and the X-ray diffraction data are combined to introduce a new ‘plasmon ruler’. This allows extraction of structural information from simple optical spectroscopy techniques, with important implications in understanding the structure of nanoparticle films at liquid interfaces and their self-assembly.
Kolomeisky AB, Kornyshev AA, 2016, Current-generating 'double layer shoe' with a porous sole, Journal of Physics: Condensed Matter, Vol: 28, ISSN: 0953-8984
We present a principle and a simple theory of a novel reverse electroactuator, in which the electrical current is generated by pumping an electrolytic liquid into nonwetting pores of a polarized electrode. The theory establishes the relationship between the variation of external pressure and the electrical current. The effective current density is amplified by the high porosity of the electrode. The suggested principle can be implemented into the design of a shoe which will generate an AC current simply by walking. Estimates of typical parameters and operation regimes of such a device suggest that one can easily generate a peak current density of ~17 mA cm−2. This would produce some 1.7 A from each shoe at 0.65 W average power density, without hampering walking.
Friedl J, Markovits IIE, Herpich M, et al., 2016, Interface between an Au(111) Surface and an Ionic Liquid: The Influence of Water on the Double-Layer Capacitance, CHEMELECTROCHEM, Vol: 4, Pages: 216-220, ISSN: 2196-0216
Sikdar D, Kornyshev A, 2016, Theory of tailorable optical response of two-dimensional arrays of plasmonic nanoparticles at dielectric interfaces, Scientific Reports, Vol: 6, ISSN: 2045-2322
Two-dimensional arrays of plasmonic nanoparticles at interfaces are promising candidates for novel optical metamaterials. Such systems materialise from ‘top–down’ patterning or ‘bottom–up’ self-assembly of nanoparticles at liquid/liquid or liquid/solid interfaces. Here, we present a comprehensive analysis of an extended effective quasi-static four-layer-stack model for the description of plasmon-resonance-enhanced optical responses of such systems. We investigate in detail the effects of the size of nanoparticles, average interparticle separation, dielectric constants of the media constituting the interface, and the nanoparticle position relative to the interface. Interesting interplays of these different factors are explored first for normally incident light. For off-normal incidence, the strong effects of the polarisation of light are found at large incident angles, which allows to dynamically tune the reflectance spectra. All the predictions of the theory are tested against full-wave simulations, proving this simplistic model to be adequate within the quasi-static limit. The model takes seconds to calculate the system’s optical response and makes it easy to unravel the effect of each system parameter. This helps rapid rationalization of experimental data and understanding of the optical signals from these novel ‘metamaterials’, optimised for light reflection or harvesting.
Dudka M, Kondrat S, Kornyshev A, et al., 2016, Phase behaviour and structure of a superionic liquid in nonpolarized nanoconfinement, Journal of Physics: Condensed Matter, Vol: 28, ISSN: 0953-8984
The ion-ion interactions become exponentially screened for ions confined in ultranarrow metallic pores. To study the phase behaviour of an assembly of such ions, called a superionic liquid, we develop a statistical theory formulated on bipartite lattices, which allows an analytical solution within the Bethe-lattice approach. Our solution predicts the existence of ordered and disordered phases in which ions form a crystal-like structure and a homogeneous mixture, respectively. The transition between these two phases can potentially be first or second order, depending on the ion diameter, degree of confinement and pore ionophobicity. We supplement our analytical results by three-dimensional off-lattice Monte Carlo simulations of an ionic liquid in slit nanopores. The simulations predict formation of ionic clusters and ordered snake-like patterns, leading to characteristic close-standing peaks in the cation-cation and anion-anion radial distribution functions.
Kondrat S, Kornyshev A, Qiao R, 2016, Two tributaries of the electrical double layer Preface, JOURNAL OF PHYSICS-CONDENSED MATTER, Vol: 28, ISSN: 0953-8984
Kolomeisky AB, Kornyshev AA, 2016, Current-generating 'double layer shoe' with a porous sole, Journal of Physics: Condensed Matter, Vol: 28, ISSN: 0953-8984
We present a principle and a simple theory of a novel reverse electroactuator, in which the electrical current is generated by pumping an electrolytic liquid into nonwetting pores of a polarized electrode. The theory establishes the relationship between the variation of external pressure and the electrical current. The effective current density is amplified by the high porosity of the electrode. The suggested principle can be implemented into the design of a shoe which will generate an AC current simply by walking. Estimates of typical parameters and operation regimes of such a device suggest that one can easily generate a peak current density of ~17 mA cm−2. This would produce some 1.7 A from each shoe at 0.65 W average power density, without hampering walking.
Kolomeisky AB, Kornyshev AA, 2016, Current-generating ‘double layer shoe’ with a porous sole, Journal of Physics: Condensed Matter, Vol: 28, ISSN: 0953-8984
We present a principle and a simple theory of a novel reverse electroactuator, in which the electrical current isgenerated by pumping of an electrolytic liquid into nonwetting pores of a polarized electrode. The theoryestablishes the relationship between the variation of external pressure and the electrical current. The effectivecurrent density is amplified by high porosity of the electrode. The suggested principle can be implementedinto a design of a shoe which will be generating an AC current simply by walking. Estimates of typicalparameters and operation regimes of such device suggest that one can easily generate a peak current densityof ~17 mA/cm2. This would produce some 1.7 A from each shoe at 0.65 W average power density, withouthampering walking.
Lee DJ, Danilowicz C, Rochester CH, et al., 2016, Evidence of protein-free homology recognition in magnetic bead force-extension experiments, Proceedings of the Royal Society A: Mathematical, Physical & Engineering Sciences, Vol: 472, ISSN: 1364-5021
Earlier theoretical studies have proposed that the homology-dependent pairing of large tracts of dsDNA may be due to physical interactions between homologous regions. Such interactions could contribute to the sequence-dependent pairing of chromosome regions that may occur in the presence or the absence of double-strand breaks. Several experiments have indicated the recognition of homologous sequences in pure electrolytic solutions without proteins. Here, we report single-molecule force experiments with a designed 60 kb long dsDNA construct; one end attached to a solid surface and the other end to a magnetic bead. The 60 kb constructs contain two 10 kb long homologous tracts oriented head to head, so that their sequences match if the two tracts fold on each other. The distance between the bead and the surface is measured as a function of the force applied to the bead. At low forces, the construct molecules extend substantially less than normal, control dsDNA, indicating the existence of preferential interaction between the homologous regions. The force increase causes no abrupt but continuous unfolding of the paired homologous regions. Simple semi-phenomenological models of the unfolding mechanics are proposed, and their predictions are compared with the data.
Sikdar D, Hasan SB, Urbakh M, et al., 2016, Unravelling the optical responses of nanoplasmonic mirror-on-mirror metamaterials., Physical Chemistry Chemical Physics, Vol: 18, Pages: 20486-20498, ISSN: 1463-9084
Mirror-on-mirror platforms based on arrays of metallic nanoparticles, arranged top-down or self-assembled on a thin metallic film, have interesting optical properties. Interaction of localized surface-plasmons in nanoparticles with propagating surface-plasmons in the film underpins the exotic features of such platforms. Here, we present a comprehensive theoretical framework which emulates such a system using a five-layer-stack model and calculate its reflectance, transmittance, and absorbance spectra. The theory rests on dipolar quasi-static approximations incorporating image-forces and effective medium theory. Systematically tested against full-wave simulations, this simple approach proves to be adequate within its obvious applicability limits. It is used to study optical signals as a function of nanoparticle dimensions, interparticle separation, metal film thickness, the gap between the film and nanoparticles, and incident light characteristics. Several peculiar features are found, e.g., quenching of reflectivity in certain frequency domains or shift of the reflectivity spectra. Schemes are proposed to tailor those as functions of the mentioned parameters. Calculating the system's optical responses in seconds, as compared to much longer running simulations, this theory helps to momentarily unravel the role of each system parameter in light reflection, transmission, and absorption, facilitating thereby the design and optimisation of novel mirror-on-mirror systems.
Rochester CC, Kondrat S, Pruessner G, et al., 2016, Charging Ultra-nanoporous Electrodes with Size-asymmetric Ions Assisted by Apolar Solvent, The Journal of Physical Chemistry C, Vol: 120, Pages: 16042-16050, ISSN: 1932-7447
We develop a statistical theory of charging quasi single-file pores with cations and anions of different sizes as well as solvent molecules or voids. This is done by mapping the charging onto a one-dimensional Blume–Emery–Griffith model with variable coupling constants. The results are supported by three-dimensional Monte Carlo simulations in which many limitations of the theory are lifted. We explore the different ways of enhancing the energy storage which depend on the competitive adsorption of ions and solvent molecules into pores, the degree of ionophilicity and the voltage regimes accessed. We identify new solvent-related charging mechanisms and show that the solvent can play the role of an “ionophobic agent”, effectively controlling the pore ionophobicity. In addition, we demonstrate that the ion-size asymmetry can significantly enhance the energy stored in a nanopore.
Qiao R, He Y, Kornyshev A, et al., 2016, Dynamic charge storage in nanopores filled with ionic liquids, Publisher: AMER CHEMICAL SOC, ISSN: 0065-7727
Demetriadou A, Kornyshev A, 2016, Principles of plasmonic imaging, Deutsche Physikalische Gesellschaft (DPG) conference
Edel JB, Kornyshev AA, Kucernak AR, et al., 2016, Fundamentals and applications of self-assembled plasmonic nanoparticles at interfaces, Chemical Society Reviews, Vol: 45, Pages: 1581-1596, ISSN: 1460-4744
This tutorial review will introduce and explore fundamental and applied aspects of using electrolytic interfaces incorporating nanoscale building blocks for use in novel applications such as sensors, and tunable optics. In order to do this, it is important to be able to understand the principles behind even the simplest of immiscible interfaces such as that of the Liquid | Liquid and Solid | Liquid Qualitatively, the picture is simple however the complexity is easily compounded by the addition of electrolyte, and further compounded by addition of more complex entities such as nanoparticles. Nevertheless combining all these components surprisingly results in an elegant solution, where the nanoparticles have the ability to self assemble at the interface with a high level of control. Importantly, this opens up the door to development of new types of materials with a range of applications which have only recently been exploited. As such initially we begin with a description of the fundamentals related to liquid | Liquid and Solid | Liquid interfaces both with and without electrolyte. The discussions then shifts to a description of biasing the interface by application of an electric field. This is followed by an exploration of nanoparticle assembly and disassembly at the interface by controlling parameters such as ligand composition, charge, pH, and electric field. Finally a description of the state-of-the-art is given in terms of current applications and possible future directions. It is perhaps fair to say that these new frontiers have caused great excitement within the sensing community not only due to the simplicity of the technique but also due to the unprecedented levels of sensitivity
Cheung KCM, Chen X, Albrecht T, et al., 2016, Principles of a Single-Molecule Rectifier in Electrolytic Environment, Journal of Physical Chemistry C, Vol: 120, Pages: 3089-3106, ISSN: 1932-7455
The idea of gating the electrical current across a single-chain molecule, confined between and linking two electrodes in electrolytic solution, in order to achieve an asymmetric current–voltage plot, was first put forward and substantiated with a detailed theory by Kornyshev and Kuznetsov (ChemPhysChem, 2006), and Kornyshev, Kuznetsov, and Ulstrup (PNAS, 2006). However, not all aspects of that effect have been studied in those papers. Its experimental confirmation, published by Capozzi et al. (Nature Nanotech., 2015), enthused us to revisit that theory, extending it and exploring all the regimes of system operation. In this article we present such comprehensive analysis, which reveals a set of new features. An important finding is that the introduction of more refined models of the electric double layer (beyond linear response) results in stronger rectification effects, already for relatively dilute electrolyte concentrations. The theory equally applies to electrode systems with and without full electrochemical potential control and highlights important differences for these two scenarios, for example, with regard to the effect of electrode surface area.
Kondrat S, Kornyshev AA, 2016, Pressing a spring: what does it take to maximize the energy storage in nanoporous supercapacitors?, Nanoscale Horizons, Vol: 1, Pages: 45-52, ISSN: 2055-6756
We discuss the nonlinear effects and efficiency of charge storage in supercapacitors with nanoporous electrodes and ionic liquids, and demonstrate that to maximize the stored energy, it may be beneficial to create ‘obstacles’ or ‘difficulties’ in charging. This can be achieved by making thermodynamically unfavourable conditions for ions inside nanopores, or more favourable outside. We show by means of Monte Carlo simulations that such ‘ionophobic’ pores store energy more efficiently and can provide equivalent or even better energy capacity. Since the recent analysis predicts much faster charging of ionophobic nanopores, we conclude that such pores offer a better option for simultaneous energy/power optimization.
Fajardo OY, Bresme F, Kornyshev AA, et al., 2015, Electrotunable friction with ionic liquid lubricants: How important is the molecular structure of the ions?, Journal of Physical Chemistry Letters, Vol: 6, Pages: 3998-4004, ISSN: 1948-7185
Using nonequilibrium molecular dynamics simulations and a coarse-grained model of ionic liquids, we have investigated the impact that the shape and the intramolecular charge distribution of the ions have on the electrotunable friction with ionic liquid nanoscale films. We show that the electric field induces significant structural changes in the film, leading to dramatic modifications of the friction force. Comparison of the present work with previous studies using different models of ionic liquids indicate that the phenomenology presented here applies to a wide range of ionic liquids. In particular, the electric-field-induced shift of the slippage plane from the solid–liquid interface to the interior of the film and the nonmonotonic variation of the friction force are common features of ionic lubricants under strong confinement. We also demonstrate that the molecular structure of the ions plays an important role in determining the electrostriction and electroswelling of the confined film, hence showing the importance of ion-specific effects in electrotunable friction.
Rochester CC, Pruessner G, Kornyshev AA, 2015, Statistical mechanics of 'Unwanted Electroactuation' in nanoporous supercapacitors, Electrochimica Acta, Vol: 174, Pages: 978-984, ISSN: 0013-4686
Nanoporous electrodes have the potential to increase the surface electrode interfacial area and the stored energy density of a supercapacitor. However, structural deformation of the electrode can become apparent when the size of the pore is comparable to the size of a charging ion. After many cycles this could cause wear and degradation. We present a theoretical study of this ‘Unwanted Electroactuation’ in a carbon electrode wetted with an ionic liquid. We incorporate changes of the carbon-carbon bond length due to electrochemical doping of the pore walls and steric effects related to counterion insertion into the pore via a modified Ising model of charge storage. When considering the total electrode deformation these effects either complement or compete with each other, depending on the polarisation of the electrode. Our model shows qualitative agreement with the features of the experimentally observed expansion caused by variation of electrode potential.
edel, turek, cecchini, et al., 2015, METHOD OF DETECTING AN ANALYTE IN A SAMPLE USING RAMAN SPECTROSCOPY, INFRA RED SPECTROSCOPY AND/OR FLUORESCENCE SPECTROSCOPY
The invention relates to a method of detecting the presence of an analyte associated with a nanoparticle layer formed at a liquid-liquid interface. The method comprises removing a portion of one of the liquid phases; and detecting the presence of the analyte by Raman spectroscopy, Infra Red spectroscopy and/or fluorescence spectroscopy. The invention further relates to a kit for use in the method, comprising a sample vessel for receiving in use, a first and second liquid phase; wherein said phases are immiscible and wherein one or both of the first or the second liquid phase comprise nanoparticles, and instructions to allow analysis of an analyte in a sample according to the claimed method
Lee DJO, Wynveen A, Albrecht T, et al., 2015, Which way up? Recognition of homologous DNA segments in parallel and antiparallel alignments, Journal of Chemical Physics, Vol: 142, ISSN: 1089-7690
Homologous gene shuffling between DNA molecules promotes genetic diversity and is an important pathway for DNA repair. For this to occur, homologous genes need to find and recognize each other. However, despite its central role in homologous recombination, the mechanism of homology recognition has remained an unsolved puzzle of molecular biology. While specific proteins are known to play a role at later stages of recombination, an initial coarse grained recognition step has, however, been proposed. This relies on the sequence dependence of the DNA structural parameters, such as twist and rise, mediated by intermolecular interactions, in particular, electrostatic ones. In this proposed mechanism, sequences that have the same base pair text, or are homologous, have lower interaction energy than those sequences with uncorrelated base pair texts. The difference between the two energies is termed the “recognition energy.” Here, we probe how the recognition energy changes when one DNA fragment slides past another, and consider, for the first time, homologous sequences in antiparallel alignment. This dependence on sliding is termed the “recognition well.” We find there is a recognition well for anti-parallel, homologous DNA tracts, but only a very shallow one, so that their interaction will differ little from the interaction between two nonhomologous tracts. This fact may be utilized in single molecule experiments specially targeted to test the theory. As well as this, we test previous theoretical approximations in calculating the recognition well for parallel molecules against MC simulations and consider more rigorously the optimization of the orientations of the fragments about their long axes upon calculating these recognition energies. The more rigorous treatment affects the recognition energy a little, when the molecules are considered rigid. When torsional flexibility of the DNA molecules is introduced, we find excellent agreement between the
Demetriadou A, Kornyshev AA, 2015, Principles of nanoparticle imaging using surface plasmons, NEW JOURNAL OF PHYSICS, Vol: 17, ISSN: 1367-2630
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- Citations: 34
Fajardo OY, Bresme F, Kornyshev AA, et al., 2015, Electrotunable Lubricity with Ionic Liquid Nanoscale Films, Scientific Reports, Vol: 5, ISSN: 2045-2322
He Y, Huang J, Sumpter BG, et al., 2015, Dynamic Charge Storage in Ionic Liquids-Filled Nanopores: Insight from a Computational Cyclic Voltammetry Study, JOURNAL OF PHYSICAL CHEMISTRY LETTERS, Vol: 6, Pages: 22-30, ISSN: 1948-7185
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- Citations: 48
Baumberg J, Nielsen M, Bozhevolnyi S, et al., 2015, Surface plasmon enhanced spectroscopies and time and space resolved methods: general discussion, FARADAY DISCUSSIONS, Vol: 178, Pages: 253-279, ISSN: 1359-6640
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Baumberg J, Noginov M, Aizpurua J, et al., 2015, Quantum plasmonics, gain and spasers: general discussion, FARADAY DISCUSSIONS, Vol: 178, Pages: 325-334, ISSN: 1359-6640
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Feng G, Jiang X, Qiao R, et al., 2014, Water in ionic liquids at electrified interfaces: the anatomy of electrosorption, ACS Nano, Vol: 8, Pages: 11685-11694, ISSN: 1936-0851
Complete removal of water from room-temperature ionic liquids is nearly impossible. For the electrochemical applications of ionic liquids, how water is distributed in the electrical double layers when the bulk liquids are not perfectly dry can potentially determine whether key advantages of ionic liquids, such as a wide electrochemical window, can be harnessed in practical systems. In this paper, we study the adsorption of water on electrode surfaces in contact with humid, imidazolium-based ionic liquids using molecular dynamics simulations. The results revealed that water molecules tend to accumulate within sub-nanometer distance from charged electrodes. At low amount of water in the bulk, the distributions of ions and of electrostatic potential in the double layer are affected weakly by the presence of water, but the spatial distribution of water molecules is strongly dependent on both. The preferential positions of water molecules in double layers are determined by the balance of several factors: the tendency to follow the positions of the maximal absolute value of the electrical field, the association with their ionic surroundings, and the propensity to settle at positions where more free space is available. The balance between these factors changes with charging the electrode, but the adsorption of water generally increases with voltage. The ion specificity of water electrosorption is manifested in the stronger presence of water near positive electrodes (where anions are the counterions) than near negative electrodes (where cations are counterions). These predictions await experimental verification.
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