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Ramesh R, Thimonier C, Desgranges S, Faugeras V, Coulouvrat F, Laurent J, Marrelec G, Contino-Pépin C, Urbach W, Tribet C, Taulier N. Acoustic Droplet Vaporization of Perfluorohexane Emulsions Induced by Heterogeneous Nucleation at an Ultrasonic Frequency of 1.1 MHz. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:15716-15729. [PMID: 37889478 DOI: 10.1021/acs.langmuir.3c02272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2023]
Abstract
Droplets made of liquid perfluorocarbon undergo a phase transition and transform into microbubbles when triggered by ultrasound of intensity beyond a critical threshold; this mechanism is called acoustic droplet vaporization (ADV). It has been shown that if the intensity of the signal coming from high ultrasonic harmonics are sufficiently high, superharmonic focusing is the mechanism leading to ADV for large droplets (>3 μm) and high frequencies (>1.5 MHz). In such a scenario, ADV is initiated due to a nucleus occurring at a specific location inside the droplet volume. But the question on what induces ADV in the case of nanometer-sized droplets and/or at low ultrasonic frequencies (<1.5 MHz) still remains. We investigated ADV of perfluorohexane (PFH) nano- and microdroplets at a frequency of 1.1 MHz and at conditions where there is no superharmonic focusing. Three types of droplets produced by microfluidics were studied: plain PFH droplets, PFH droplets containing many nanometer-sized water droplets, and droplets made of a PFH corona encapsulating a single micron-sized water droplet. The probability to observe a vaporization event was measured as a function of acoustic pressure. As our experiments were performed on droplet suspensions containing a population of monodisperse droplets, we developed a statistical model to extrapolate, from our experimental curves, the ADV pressure thresholds in the case where only one droplet would be insonified. We observed that the value of ADV pressure threshold decreases as the radius of a plain PFH droplet increases. This value was further reduced when a PFH droplet encapsulates a micron-sized water droplet, while the encapsulation of many nanometer-sized water droplets did not modify the threshold. These results cannot be explained by a model of homogeneous nucleation. However, we developed a heterogeneous nucleation model, where the nucleus appears at the surface in contact with PFH, that successfully predicts our experimental ADV results.
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Affiliation(s)
- R Ramesh
- CNRS, INSERM, Laboratoire d'Imagerie Biomédicale, LIB, Sorbonne Université, F-75006 Paris, France
- Laboratoire de Physique de l'École Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris Cité, F-75005 Paris, France
| | - C Thimonier
- CNRS, INSERM, Laboratoire d'Imagerie Biomédicale, LIB, Sorbonne Université, F-75006 Paris, France
- Laboratoire de Physique de l'École Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris Cité, F-75005 Paris, France
- Département de Chimie, P.A.S.T.E.U.R., École Normale Supérieure, Université PSL, Sorbonne Université, CNRS, 75005 Paris, France
| | - S Desgranges
- Équipe Systèmes Amphiphiles Bioactifs et Formulations Eco-compatibles, UPRI, Avignon Université, 84000 Avignon, France
| | - V Faugeras
- Laboratoire de Physique de l'École Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris Cité, F-75005 Paris, France
| | - F Coulouvrat
- Institut Jean le Rond d'Alembert, CNRS, Sorbonne Université, 4 Place Jussieu, 75005 Paris, France
| | - J Laurent
- Laboratoire de Physique et Mécanique des Milieux Hétérogénes, CNRS, ESPCI Paris, PSL Research University, Sorbonne Université, Université Paris Cité, 75005 Paris, France
| | - G Marrelec
- CNRS, INSERM, Laboratoire d'Imagerie Biomédicale, LIB, Sorbonne Université, F-75006 Paris, France
| | - C Contino-Pépin
- Équipe Systèmes Amphiphiles Bioactifs et Formulations Eco-compatibles, UPRI, Avignon Université, 84000 Avignon, France
| | - W Urbach
- Laboratoire de Physique de l'École Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris Cité, F-75005 Paris, France
| | - C Tribet
- PASTEUR, Département de Chimie, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France
| | - N Taulier
- CNRS, INSERM, Laboratoire d'Imagerie Biomédicale, LIB, Sorbonne Université, F-75006 Paris, France
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Direct Correlation of Surface Tension and Surface Composition of Ionic Liquid Mixtures-A Combined Vacuum Pendant Drop and Angle-Resolved X-ray Photoelectron Spectroscopy Study. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27238561. [PMID: 36500653 PMCID: PMC9736233 DOI: 10.3390/molecules27238561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 11/29/2022] [Accepted: 12/01/2022] [Indexed: 12/12/2022]
Abstract
We investigated the surface tension and surface composition of various mixtures of the two ionic liquids (ILs) 1-methyl-3-octyl-imidazolium hexafluorophosphate [C8C1Im][PF6] and 1,3-bis(polyethylene glycol)imidazolium iodide [(mPEG2)2Im]I in the temperature range from 230 to 370 K under ultraclean vacuum conditions. The surface tension was measured using a newly developed apparatus, and the surface composition was determined by angle-resolved X-ray photoelectron spectroscopy (ARXPS). In the pure ILs, the alkyl chains of [C8C1Im][PF6] and the PEG chains of [(mPEG2)2Im]I are enriched at the IL/vacuum interface. In the mixtures, a strong selective surface enrichment of the alkyl chains occurs, which is most pronounced at low [C8C1Im][PF6] contents. For the surface tension, strong deviations from an ideal mixing behaviour take place. By applying a simple approach based on the surface composition of the mixtures as deduced from ARXPS, we are able to predict and reproduce the experimentally measured temperature-dependent surface tension values with astonishingly high accuracy.
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Purcell SM, Lane PD, D'Andrea L, Elstone NS, Bruce DW, Slattery JM, Smoll EJ, Greaves SJ, Costen ML, Minton TK, McKendrick KG. Surface Structure of Alkyl/Fluoroalkylimidazolium Ionic-Liquid Mixtures. J Phys Chem B 2022; 126:1962-1979. [PMID: 35225614 PMCID: PMC9007465 DOI: 10.1021/acs.jpcb.1c10460] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The gas-liquid interface of ionic liquids (ILs) is critically important in many applications, for example, in supported IL phase (SILP) catalysis. Methods to investigate the interfacial structure in these systems will allow their performance to be improved in a rational way. In this study, reactive-atom scattering (RAS), surface tension measurements, and molecular dynamics (MD) simulations were used to study the vacuum interface of mixtures of partially fluorinated and normal alkyl ILs. The underlying aim was to understand whether fluorinated IL ions could be used as additives to modify the surface structure of one of the most widely used families of alkyl ILs. The series of ILs 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Cnmim][Tf2N]) with n = 4-12 were mixed with a fixed-length, semiperfluorinated analogue (1H,1H,2H,2H-perfluorooctyl)-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C8mimF13][Tf2N]), forming [Cnmim](1-x)[C8mimF13]x[Tf2N] mixtures, where x is the bulk mole fraction of the fluorinated component. The RAS-LIF method combined O-atom projectiles with laser-induced fluorescence (LIF) detection of the product OH as a measure of surface exposure of the alkyl chains. For [C8mim](1-x)[C8mimF13]x[Tf2N] mixtures, RAS-LIF OH yields are below those expected from stoichiometry. There are quantitatively consistent negative deviations from linearity of the surface tension. Both results imply that the lower-surface-tension fluoroalkyl material dominates the surface. A similar deficit is found for alkyl chain lengths n = 4, 6, 8, and 12 and for all (nonzero) x investigated by RAS-LIF. Accessible-surface-area (ASA) analyses of the MD simulations for [Cnmim](1-x)[C8mimF13]x[Tf2N] mixtures qualitatively reproduce the same primary effect of fluoro-chain predominance of the surface over most of the range of n. However, there are significant quantitative discrepancies between MD ASA predictions and experiment relating to the strength of any n-dependence of the relative alkyl coverage at fixed x, and on the x-dependence at fixed n. These discrepancies are discussed in the context of detailed examinations of the surface structures predicted in the MD simulations. Potential explanations, beyond experimental artifacts, include inadequacies in the classical force fields used in the MD simulations or the inability of simple ASA algorithms to capture dynamical factors that influence RAS-LIF yields.
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Affiliation(s)
- Simon M Purcell
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
| | - Paul D Lane
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
| | - Lucía D'Andrea
- Department of Chemistry, University of York, Heslington, York YO10 5DD, U.K
| | - Naomi S Elstone
- Department of Chemistry, University of York, Heslington, York YO10 5DD, U.K
| | - Duncan W Bruce
- Department of Chemistry, University of York, Heslington, York YO10 5DD, U.K
| | - John M Slattery
- Department of Chemistry, University of York, Heslington, York YO10 5DD, U.K
| | - Eric J Smoll
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, United States
| | - Stuart J Greaves
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
| | - Matthew L Costen
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
| | - Timothy K Minton
- Ann and H.J. Smead Department of Aerospace Engineering Sciences, University of Colorado Boulder, Boulder, Colorado 80303, United States
| | - Kenneth G McKendrick
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
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Koyama Y, Shimono S, Abe H, Matsuishi K. Crystal polymorphs in 1-alkyl-3-methylimidazolium perfluorobutanesulfonate ionic liquids. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.113908] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Characterization of Local Structures of Confined Imidazolium Ionic Liquids in PVdF-co-HFP Matrices by High Pressure Infrared Spectroscopy. NANOMATERIALS 2020; 10:nano10101973. [PMID: 33028010 PMCID: PMC7600376 DOI: 10.3390/nano10101973] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 09/29/2020] [Accepted: 09/30/2020] [Indexed: 01/01/2023]
Abstract
The nanoscale ion ordering of ionic liquids at confined interfaces under high pressures was investigated in this study. 1-Hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([HMIM][NTf2])/poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-co-HFP) and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM][NTf2])/PVdF-co-HFP were prepared and characterized by using high-pressure infrared spectroscopy. Under ambient pressure, imidazolium C2–H and C4,5–H absorptions were blue-shifted in frequency due to the presence of PVdF-co-HFP. However, the absorption of anionic νa SO2 did not reveal any significant shifts in frequency upon dilution by PVdF-co-HFP. The experimental results suggest that PVdF-co-HFP disturbs the local structures of the imidazolium C–H groups instead of the anionic SO2 groups. The frequency shifts of C4,5–H became dramatic for the mixtures at high pressures. These results suggest that pressure-enhanced ionic liquid–polymer interactions may play an appreciable role in IL-PVdF-co-HFP systems under high pressures. The pressure-induced blue-shifts due to the PVdF-co-HFP additions were more obvious for the [HMIM][NTf2] mixtures than for [EMIM][NTf2] mixtures.
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Heller BS, Paap U, Maier F, Steinrück HP. Pronounced surface enrichment of fluorinated ionic liquids in binary mixtures with methoxy-functionalized ionic liquids. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.112783] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Warmińska D, Cichowska-Kopczyńska I. Thermodynamic study of binary mixtures of toluene with ionic liquids, 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide, 1-hexyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide and 1-butylpyridinium bis(trifluoromethylsulfonyl)imide. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.112754] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Heller BSJ, Lexow M, Greco F, Shin S, Partl G, Maier F, Steinrück HP. Temperature-Dependent Surface Enrichment Effects in Binary Mixtures of Fluorinated and Non-Fluorinated Ionic Liquids. Chemistry 2020; 26:1117-1126. [PMID: 31633251 PMCID: PMC7027538 DOI: 10.1002/chem.201904438] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Indexed: 11/05/2022]
Abstract
Using angle-resolved X-ray photoelectron spectroscopy (ARXPS), we investigate the topmost nanometers of various binary ionic liquid (IL) mixtures at different temperatures in the liquid state. The mixtures consist of ILs with the same [PF6 ]- anion but two different cations, namely 3-methyl-1-(3,3,4,4,4-pentafluorobutyl)imidazolium hexafluorophosphate, [PFBMIm][PF6 ], and 1-butyl-3-methylimidazolium hexafluorophosphate, [C4 C1 Im][PF6 ], with 10, 25, 50 and 75 mol % content of [PFBMIm][PF6 ]. We observe a preferential enrichment of the fluorinated chain in the topmost layer, relative to the bulk composition, which is most pronounced for the lowest content of [PFBMIm][PF6 ]. Upon cooling the mixtures stepwise from 95 °C until surface charging effects in XPS indicate solidification, we observe a pronounced increase in surface enrichment of the fluorinated chain with decreasing temperature in the liquid state. In contrast to the mixtures with lower [PFBMIm][PF6 ] contents, cooling the 75 mol % mixture additionally shows an abrupt decrease of the fluorinated chain signal before complete solidification occurs, which is assigned to partial precipitation effects.
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Affiliation(s)
- Bettina S J Heller
- Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058, Erlangen, Germany
| | - Matthias Lexow
- Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058, Erlangen, Germany
| | - Francesco Greco
- Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058, Erlangen, Germany
| | - Sunghwan Shin
- Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058, Erlangen, Germany
| | - Gabriel Partl
- Institut für Allgemeine, Anorganische und Theoretische Chemie, Leopold-Franzens-Universität Innsbruck, Innrain 80-82, 6020, Innsbruck, Austria
| | - Florian Maier
- Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058, Erlangen, Germany
| | - Hans-Peter Steinrück
- Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058, Erlangen, Germany
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Prikhod’ko SA, Shabalin AY, Shmakov MM, Bardin VV, Adonin NY. Ionic liquids with fluorine-containing anions as a new class of functional materials: features of the synthesis, physicochemical properties, and use. Russ Chem Bull 2020. [DOI: 10.1007/s11172-020-2719-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Systematic study of the influence of the molecular structure of fluorinated ionic liquids on the solubilization of atmospheric gases using a soft-SAFT based approach. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2019.111645] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Martins MAR, Carvalho PJ, Alves D, Dariva C, Costa MC, Ferreira RAS, André PS, Morgado P, Pinho SP, Filipe EJM, Coutinho JAP. Surface crystallization of ionic liquid crystals. Phys Chem Chem Phys 2019; 21:17792-17800. [PMID: 31372606 DOI: 10.1039/c9cp03947c] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The evidence for surface crystallization in ionic liquids is scarce. The existing reports seem to be contradictory as for its driving forces, since in the two compounds investigated in the literature, the contribution of coloumbic and van der Waals forces is very different. In this work 1-dodecyl-3-methylimidazolium tetrafluoroborate was studied and its surface crystallization characterized by surface tension, ellipsometry and optical microscopy. The results obtained seem to reconcile previous observations, and it was further shown, using the same techniques, that this phenomenon is prevalent in other ionic liquids. MD simulation results illustrate the different possibilities of organization, providing reasonable models to rationalize the experimental observations.
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Vieira NS, Bastos JC, Hermida-Merino C, Pastoriza-Gallego MJ, Rebelo LP, Piñeiro MM, Araújo JM, Pereiro AB. Aggregation and phase equilibria of fluorinated ionic liquids. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2019.04.086] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Esperança JMSS, Tariq M, Pereiro AB, Araújo JMM, Seddon KR, Rebelo LPN. Anomalous and Not-So-Common Behavior in Common Ionic Liquids and Ionic Liquid-Containing Systems. Front Chem 2019; 7:450. [PMID: 31281812 PMCID: PMC6596442 DOI: 10.3389/fchem.2019.00450] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 06/05/2019] [Indexed: 11/27/2022] Open
Abstract
This work highlights unexpected, not so well known responses of ionic liquids and ionic liquid-containing systems, which are reported in a collective manner, as a short review. Examples include: (i) Minima in the temperature dependence of the isobaric thermal expansion coefficient of some ILs; (ii) Viscosity Minima in binary mixtures of IL + Molecular solvents; (iii) Anomalies in the surface tension within a family of ILs; (iv) The constancy among IL substitution of Cp/Vm at and around room temperature; (v) ILs as glass forming liquids; (vi) Alternate odd-even side alkyl chain length effects; (vii) Absolute negative pressures in ILs and IL-containing systems; (viii) Reversed-charged ionic liquid pairs; (ix) LCST immiscibility behavior in IL + solvent systems.
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Affiliation(s)
- José M S S Esperança
- LAQV/REQUIMTE, Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, Caparica, Portugal
| | - Mohammad Tariq
- LAQV/REQUIMTE, Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, Caparica, Portugal
| | - Ana B Pereiro
- LAQV/REQUIMTE, Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, Caparica, Portugal
| | - João M M Araújo
- LAQV/REQUIMTE, Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, Caparica, Portugal
| | - Kenneth R Seddon
- QUILL Research Centre, the Queen's University of Belfast, Belfast, United Kingdom
| | - Luis Paulo N Rebelo
- LAQV/REQUIMTE, Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, Caparica, Portugal
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Lexow M, Heller BSJ, Partl G, Bhuin RG, Maier F, Steinrück HP. Cation Exchange at the Interfaces of Ultrathin Films of Fluorous Ionic Liquids on Ag(111). LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:398-405. [PMID: 30540199 PMCID: PMC6377181 DOI: 10.1021/acs.langmuir.8b03517] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
In the context of applications with thin ionic liquid (IL) films on solid supports, we studied the ion distribution within mixed thin IL films by angle-resolved X-ray photoelectron spectroscopy. After the deposition of 1-methyl-3-octylimidazolium hexafluorophosphate, [C8C1Im][PF6], on top of a wetting layer (WL) of 3-methyl-1-(3,3,4,4,4-pentafluorobutyl)imidazolium hexafluorophosphate, [PFBMIm][PF6], on Ag(111) at room temperature (RT), we find a preferential enrichment of the [PFBMIm]+ cation at the IL/vacuum interface. In a similar deposition experiment at 82 K, this cation exchange at the IL/solid interface does not occur. Upon heating the film from 82 K to RT, we observe the replacement of [C8C1Im]+ by [PFBMIm]+ at the IL/vacuum interface between ∼160 and ∼220 K. No further changes in the surface composition were observed between 220 K and RT. Upon further heating the mixed IL film, we find the complete desorption of [PFBMIm][PF6] from the mixed film below 410 K, leaving a WL of pure [C8C1Im][PF6] on Ag(111), which desorbs until 455 K.
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Affiliation(s)
- Matthias Lexow
- Lehrstuhl
für Physikalische Chemie 2, Friedrich-Alexander-Universität
Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen, Germany
- M.L.: E-mail,
| | - Bettina S. J. Heller
- Lehrstuhl
für Physikalische Chemie 2, Friedrich-Alexander-Universität
Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen, Germany
| | - Gabriel Partl
- Institut
für Allgemeine, Anorganische und Theoretische Chemie, Leopold-Franzens-Universität Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Radha G. Bhuin
- Lehrstuhl
für Physikalische Chemie 2, Friedrich-Alexander-Universität
Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen, Germany
| | - Florian Maier
- Lehrstuhl
für Physikalische Chemie 2, Friedrich-Alexander-Universität
Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen, Germany
| | - Hans-Peter Steinrück
- Lehrstuhl
für Physikalische Chemie 2, Friedrich-Alexander-Universität
Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen, Germany
- H.-P.S.: E-mail,
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Ferreira ML, Araújo JMM, Pereiro AB, Vega LF. Insights into the influence of the molecular structures of fluorinated ionic liquids on their thermophysical properties. A soft-SAFT based approach. Phys Chem Chem Phys 2019; 21:6362-6380. [DOI: 10.1039/c8cp07522k] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Development of predictive models for FILs.
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Affiliation(s)
- Margarida L. Ferreira
- LAQV
- REQUIMTE
- Departamento de Química
- Faculdade de Ciências e Tecnologia
- Universidade Nova de Lisboa
| | - João M. M. Araújo
- LAQV
- REQUIMTE
- Departamento de Química
- Faculdade de Ciências e Tecnologia
- Universidade Nova de Lisboa
| | - Ana B. Pereiro
- LAQV
- REQUIMTE
- Departamento de Química
- Faculdade de Ciências e Tecnologia
- Universidade Nova de Lisboa
| | - Lourdes F. Vega
- Gas Research Center
- Catalysis and Separation Center (CeCas) and Chemical Engineering Department
- Khalifa University
- Abu Dhabi
- United Arab Emirates
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Griffin LR, Browning KL, Clarke SM, Smith AM, Perkin S, Skoda MWA, Norman SE. Direct measurements of ionic liquid layering at a single mica-liquid interface and in nano-films between two mica-liquid interfaces. Phys Chem Chem Phys 2018; 19:297-304. [PMID: 27905590 DOI: 10.1039/c6cp05757h] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The layering of ionic liquids close to flat, charged interfaces has been identified previously through theoretical and some experimental measurements. Here we present evidence for oscillations in ion density ('layering') in a long chain ionic liquid (1-decyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide) near the interface with mica using two complementary approaches. Neutron reflection at the ionic liquid-mica interface is used to detect structure at a single interface, and surface force balance (SFB) measurements carried out with the same ionic liquid reveal oscillatory density in the liquid confined between two mica sheets. Our findings imply the interfacial structure is not induced by confinement alone. Structural forces between two mica surfaces extend to approximately twice the distance of the density oscillations measured at a single interface and have similar period in both cases.
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Affiliation(s)
- Lucy R Griffin
- BP Institute and Department of Chemistry, University of Cambridge, Cambridge, UK.
| | - Kathryn L Browning
- BP Institute and Department of Chemistry, University of Cambridge, Cambridge, UK.
| | - Stuart M Clarke
- BP Institute and Department of Chemistry, University of Cambridge, Cambridge, UK.
| | - Alexander M Smith
- Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, UK
| | - Susan Perkin
- Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, UK
| | - M W A Skoda
- ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Campus, Didcot OX11 0QX, UK
| | - Sarah E Norman
- ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Campus, Didcot OX11 0QX, UK
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19
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Rauber D, Heib F, Schmitt M, Hempelmann R. Trioctylphosphonium room temperature ionic liquids with perfluorinated groups – Physical properties and surface behavior in comparison with the nonfluorinated analogues. Colloids Surf A Physicochem Eng Asp 2018. [DOI: 10.1016/j.colsurfa.2017.10.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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20
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Bastos JC, Carvalho SF, Welton T, Canongia Lopes JN, Rebelo LPN, Shimizu K, Araújo JMM, Pereiro AB. Design of task-specific fluorinated ionic liquids: nanosegregation versus hydrogen-bonding ability in aqueous solutions. Chem Commun (Camb) 2018; 54:3524-3527. [DOI: 10.1039/c8cc00361k] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Fluorinated ionic liquids rich-nanosegregated behaviour reduces the impact of the addition of water upon the ionic liquids's H-bond acceptance ability.
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Affiliation(s)
- Joana C. Bastos
- LAQV
- REQUIMTE
- Departamento de Química
- Faculdade de Ciências e Tecnologia
- Universidade Nova de Lisboa
| | - Sara F. Carvalho
- LAQV
- REQUIMTE
- Departamento de Química
- Faculdade de Ciências e Tecnologia
- Universidade Nova de Lisboa
| | - Tom Welton
- Department of Chemistry
- Imperial College London
- London
- UK
| | - José N. Canongia Lopes
- Centro de Química Estrutural
- Instituto Superior Técnico
- Universidade de Lisboa
- 1049-001 Lisboa
- Portugal
| | - Luís Paulo N. Rebelo
- LAQV
- REQUIMTE
- Departamento de Química
- Faculdade de Ciências e Tecnologia
- Universidade Nova de Lisboa
| | - Karina Shimizu
- Centro de Química Estrutural
- Instituto Superior Técnico
- Universidade de Lisboa
- 1049-001 Lisboa
- Portugal
| | - João M. M. Araújo
- LAQV
- REQUIMTE
- Departamento de Química
- Faculdade de Ciências e Tecnologia
- Universidade Nova de Lisboa
| | - Ana B. Pereiro
- LAQV
- REQUIMTE
- Departamento de Química
- Faculdade de Ciências e Tecnologia
- Universidade Nova de Lisboa
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21
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Smoll EJ, Tesa-Serrate MA, Purcell SM, D'Andrea L, Bruce DW, Slattery JM, Costen ML, Minton TK, McKendrick KG. Determining the composition of the vacuum-liquid interface in ionic-liquid mixtures. Faraday Discuss 2018; 206:497-522. [PMID: 28944811 DOI: 10.1039/c7fd00175d] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The vacuum-liquid interfaces of a number of ionic-liquid mixtures have been investigated using the combination of reactive-atom scattering with laser-induced fluorescence detection (RAS-LIF), selected surface tension measurements, and molecular dynamics (MD) simulations. The mixtures are based on the widespread 1-alkyl-3-methylimidazolium ([Cnmim]+) cation, including mixed cations which differ in chain length or chemical functionality with a common anion; and different anions for a common cation. RAS-LIF results imply that the surface compositions exhibit a general form of non-stoichiometric behaviour that mimics the well-known Henry's and Raoult's laws at low and high mole fraction, respectively. The extended Langmuir model provides a moderately good single-parameter fit, but higher-order terms are required for an accurate description. The quantitative relationship between RAS-LIF and surface tension, which probes the surface composition only indirectly, is explored for mixtures of [C2mim]+ and [C12mim]+ with a common bis(trifluoromethylsulfonyl)imide ([NTf2]-) anion. Extended Langmuir model fits to surface tension data are broadly consistent with those to RAS-LIF; however, several other common approaches to extracting surface compositions from measured surface tensions result in much larger discrepancies. MD simulations suggest that RAS-LIF faithfully reports on the alkyl-chain exposure at the surface, which is only subtly modified by composition-dependent structural reorganisation.
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Affiliation(s)
- E J Smoll
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, USA.
| | - M A Tesa-Serrate
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK.
| | - S M Purcell
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK.
| | - L D'Andrea
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK
| | - D W Bruce
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK
| | - J M Slattery
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK
| | - M L Costen
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK.
| | - T K Minton
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, USA.
| | - K G McKendrick
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK.
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22
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Derivation of the Butler equation from the requirement of the minimum Gibbs energy of a solution phase, taking into account its surface area. Colloids Surf A Physicochem Eng Asp 2017. [DOI: 10.1016/j.colsurfa.2017.09.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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23
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Pereiro AB, Llovell F, Araújo JMM, Santos ASS, Rebelo LPN, Piñeiro MM, Vega LF. Thermophysical Characterization of Ionic Liquids Based on the Perfluorobutanesulfonate Anion: Experimental and Soft-SAFT Modeling Results. Chemphyschem 2017; 18:2012-2023. [PMID: 28474438 DOI: 10.1002/cphc.201700327] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 05/01/2017] [Indexed: 11/08/2022]
Abstract
Fluorinated ionic liquids (FILs) exhibit complex molecular behavior, where three different nanodomains (polar, hydrogenated nonpolar, and fluorinated nonpolar) have been identified by molecular simulations. Given the high number of possible anion/cation combinations, a theoretical tool able to describe the thermophysical properties of these compounds in a systematic, rapid, and accurate manner is highly desirable. We present here a combined experimental-theoretical methodology to obtain the phase, interface, and transport properties of the 1-alkyl-3-methylimidazolium perfluorobutanesulfonate ([Cn C1 Im][C4 F9 SO3 ]) family. In addition to providing new experimental data, an extended version of the Statistical Associating Fluid Theory (soft-SAFT) is used to describe the physicochemical behavior of the [Cn C1 Im][C4 F9 SO3 ] family. A mesoscopic molecular model is built based on the analysis of the chemical structures of these FILs, and supported by quantum chemical calculations to study the charge distribution of the anion, where only the basic physical features are considered. The resulting molecular parameters are related to the molecular weight, providing the basis for thermophysical predictions of similar compounds. The theory is also able to predict the minimum in the surface tension versus the length of the hydrogenated alkyl chain, experimentally found at n=8. The viscosity parameters are also in agreement with the free-volume calculations obtained from experiments.
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Affiliation(s)
- Ana B Pereiro
- LAQV, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516, Caparica, Portugal.,Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, ITQB NOVA, Avenida da República, 2780-157, Oeiras, Portugal
| | - Fèlix Llovell
- Departament d'Enginyeria Química i Ciència de Materials, IQS School of Engineering, Universitat Ramon Llull, Via Augusta, 390, 08017, Barcelona, Spain
| | - João M M Araújo
- LAQV, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516, Caparica, Portugal.,Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, ITQB NOVA, Avenida da República, 2780-157, Oeiras, Portugal
| | - Andreia S S Santos
- LAQV, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516, Caparica, Portugal.,Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, ITQB NOVA, Avenida da República, 2780-157, Oeiras, Portugal
| | - Luís Paulo N Rebelo
- LAQV, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516, Caparica, Portugal.,Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, ITQB NOVA, Avenida da República, 2780-157, Oeiras, Portugal
| | - Manuel M Piñeiro
- Departamento de Física Aplicada, Facultade de Ciencias, Universidade de Vigo, E36310, Vigo, Spain
| | - Lourdes F Vega
- Alya Technology & Innovation, CPE, C/ Tres Creus 236, 08203, Sabadell, Barcelona, Spain.,Gas Research Center and Chemical Engineering Department, Khalifa University of Science and Technology, The Petroleum Institute, P.O. Box 2533, Abu Dhabi, United Arab Emirates
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24
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Rauber D, Zhang P, Huch V, Kraus T, Hempelmann R. Lamellar structures in fluorinated phosphonium ionic liquids: the roles of fluorination and chain length. Phys Chem Chem Phys 2017; 19:27251-27258. [DOI: 10.1039/c7cp04814a] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
We report a new lamellar superstructure and non-Newtonian shear thinning behavior in fluorinated phosphonium dicyanamide ILs.
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Affiliation(s)
| | - Peng Zhang
- INM-Leibniz Institute for New Materials
- 66123 Saarbrücken
- Germany
| | | | - Tobias Kraus
- INM-Leibniz Institute for New Materials
- 66123 Saarbrücken
- Germany
- Colloid and Interface Chemistry
- Saarland University
| | - Rolf Hempelmann
- Saarland University
- 66123 Saarbrücken
- Germany
- Transfercentre Sustainable Electrochemistry
- Saarland University and KIST Europe
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