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Oka T, Ohta N, Hyde ST. Polar-Nonpolar Interfaces of Normal Bicontinuous Cubic Phases in Nonionic Surfactant/Water Systems Are Parallel to the Gyroid Surface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:8687-8694. [PMID: 32610905 DOI: 10.1021/acs.langmuir.0c00597] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We investigated the structures of normal (type I) bicontinuous cubic phases in hexa-, hepta-, and octaethylene glycol dodecyl ether/water mixtures by small-angle X-ray crystallography of single-crystal domains. Reconstructed electron densities showed that the hydrophilic chains with high electron density are confined to a film centered on the surface of the Gyroid (a triply periodic minimal surface), while hydrophobic chains with low electron density are distributed within the pair of interwoven labyrinths carved out by the Gyroid. Further, the local minimum within the high electron density region, due to bulk water, coincides precisely with the Gyroid. This minimum is less pronounced in mixtures with longer ethylene glycol chains, consistent with their decreased water content. Our analysis clearly shows that the polar-nonpolar interfaces are parallel to the Gyroid surface in all mixtures. The repulsive hydration or overlapping force between the pair of facing monolayers of ethylene glycol chains on either side of the Gyroid surface is the likely origin of the parallel interfaces.
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Affiliation(s)
| | - Noboru Ohta
- SPring-8/JASRI, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198, Japan
| | - Stephen T Hyde
- Department of Applied Mathematics, Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 2601, Australia
- School of Chemistry, University of Sydney, New South Wales 2006, Australia
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2
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Assaker K, Stébé MJ, Blin JL. Mesoporous silica materials from diluted and concentrated solutions of nonionic fluorinated and ionic hydrogenated surfactants mixtures. Colloids Surf A Physicochem Eng Asp 2018. [DOI: 10.1016/j.colsurfa.2017.02.056] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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3
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Gustafsson H, Holmberg K. Emulsion-based synthesis of porous silica. Adv Colloid Interface Sci 2017; 247:426-434. [PMID: 28318490 DOI: 10.1016/j.cis.2017.03.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 02/11/2017] [Accepted: 03/10/2017] [Indexed: 10/20/2022]
Abstract
We review the use of various types of emulsions as media for synthesis of porous silica particles. The use of high internal phase emulsions, i.e. emulsions with a high ratio of dispersed to continuous phase, is an approach that has attracted considerable attention. Polymerization of the continuous phase followed by removal of the dispersed phase leads to a material with an even distribution of pores if the emulsion droplets are uniform in size. Another route is to use particle stabilized emulsions as template. This will lead to either hydrophilic or hydrophobic porous silica particles depending on whether the templating emulsion is oil-in-water or water-in-oil, respectively. Use of double emulsions as templates is a way to obtain porous particles with hierarchical porosity, usually both macropores and mesopores. Templating amphiphiles, which are often polyoxyethylene-polyoxypropylene-polyoxyethylene block copolymers, are needed in order to obtain materials with highly ordered pore structure. Non-ordered mesoporous silica with small particle size and relatively large pores can be obtained by emulsifying a silica precursor together with an inert solvent in water and allowing the silica to gel within the drops. Hollow silica spheres, i.e. spherical particles with a void in the middle, can be prepared by using emulsion drops as templates around which silica polymerizes. The particles have nanometer-sized pores penetrating the shell.
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4
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Riachy P, Lopez G, Emo M, Stébé MJ, Blin JL, Ameduri B. Investigation of a novel fluorinated surfactant-based system for the design of spherical wormhole-like mesoporous silica. J Colloid Interface Sci 2017; 487:310-319. [DOI: 10.1016/j.jcis.2016.10.053] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 10/18/2016] [Accepted: 10/19/2016] [Indexed: 12/20/2022]
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5
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Blin J, Michaux F, Stébé M. Nanostuctured mesoporous materials from different silica sources using fluorinated surfactants as templates. Colloids Surf A Physicochem Eng Asp 2016. [DOI: 10.1016/j.colsurfa.2016.04.067] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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6
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Sun B, Zhou G, Zhang H. Synthesis, functionalization, and applications of morphology-controllable silica-based nanostructures: A review. PROG SOLID STATE CH 2016. [DOI: 10.1016/j.progsolidstchem.2016.01.001] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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7
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Investigation of mixed fluorinated and triblock copolymer liquid crystals: Imprint for mesostructured bimodal silica. J Colloid Interface Sci 2015; 446:170-6. [DOI: 10.1016/j.jcis.2015.01.030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Revised: 01/14/2015] [Accepted: 01/14/2015] [Indexed: 11/17/2022]
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8
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Salama IE, Jenkins CL, Davies A, Clark JN, Wilkes AR, Hall JE, Paul A. Volatile fluorinated nanoemulsions: A chemical route to controlled delivery of inhalation Anesthesia. J Colloid Interface Sci 2015; 440:78-83. [DOI: 10.1016/j.jcis.2014.10.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Revised: 10/13/2014] [Accepted: 10/16/2014] [Indexed: 10/24/2022]
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9
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Schmitt J, Impéror-Clerc M, Michaux F, Blin JL, Stébé MJ, Pedersen JS, Meneau F. Formation of nanostructured silica materials templated with nonionic fluorinated surfactant followed by in situ SAXS. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:2007-2023. [PMID: 23305390 DOI: 10.1021/la304648j] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The formation of two-dimensional (2D)-hexagonal (p6m) silica-based hybrid materials from concentrated micellar solutions (10 wt %) of two nonionic fluorinated surfactants, R(7)(F)(EO)(8) and R(8)(F)(EO)(9), is investigated in situ using synchrotron time-resolved small angle X-ray scattering (SAXS). The two surfactants form direct micelles with different structures prior to the silica precursor addition as demonstrated by SAXS and SANS. R(8)(F)(EO)(9) gives spherical micelles and R(7)(F)(EO)(8) more complex ones, modeled here as short wormlike micelles. The in situ SAXS experiments reveal that both surfactants form well-ordered 2D-hexagonal hybrid materials after the addition of the silica precursor, in coexistence with an excess of surfactant micelles. The structures of both 2D-hexagonal phases are compared just after precipitation, and it is found that more robust and larger silica walls are formed for R(8)(F)(EO)(9) than for R(7)(F)(EO)(8). This could explain why only the material obtained with R(8)(F)(EO)(9) is stable upon washing, as observed previously. Moreover, it is proposed that in both cases, only a part of the micelles interact with the silica oligomers and undergo structural modifications before forming the 2D-hexagonal mesophase. The obtained results are finally discussed in the more general framework of the templating mechanism for nonionic surfactants.
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Affiliation(s)
- Julien Schmitt
- Laboratoire de Physique de Solides, UMR 8502, Bât. 510, Université Paris-Sud, F-91405 Orsay, France
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Stébé MJ, Emo M, Forny-Le Follotec A, Metlas-Komunjer L, Pezron I, Blin JL. Triblock siloxane copolymer surfactant: template for spherical mesoporous silica with a hexagonal pore ordering. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:1618-1626. [PMID: 23305163 DOI: 10.1021/la304315v] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Ordered mesoporous silica materials with a spherical morphology have been prepared for the first time through the cooperative templating mechanism (CTM) by using a silicone triblock copolymer as template. The behavior of the pure siloxane copolymer amphiphile in water was first investigated. A direct micellar phase (L(1)) and a hexagonal (H(1)) liquid crystal were found. The determination of the structural parameters by SAXS measurements leads us to conclude that in the hexagonal liquid crystal phase a part of the ethylene oxide group is not hydrated as observed for the micelles. Mesoporous materials were then synthesized from the cooperative templating mechanism. The recovered materials were characterized by SAXS measurements, nitrogen adsorption-desorption analysis, and transmission and scanning electron microscopy. The results clearly evidence that one can control the morphology and the nanostructuring of the resulting material by modifying the synthesis parameters. Actually, highly ordered mesoporous materials with a spherical morphology have been obtained with a siloxane copolymer/tetramethoxysilane molar ratio of 0.10 after hydrothermal treatment at 100 °C. Our study also supports the fact that the interactions between micelles and the hydrolyzed precursor are one of the key parameters governing the formation of ordered mesostructures through the cooperative templating mechanism. Indeed, we have demonstrated that when the interactions between micelles are important, only wormhole-like structures are recovered.
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Affiliation(s)
- M J Stébé
- SRSMC, UMR7565, Université de Lorraine, F-54506 Vandoeuvre-lès-Nancy cedex, France
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11
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Szymczyk K. Correlation between the Adsorption of the Fluorocarbon Surfactants at the Polymer–Solution and Solution–Air Interfaces and the Parameter of the Interfacial Interaction. Ind Eng Chem Res 2012. [DOI: 10.1021/ie3016544] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Katarzyna Szymczyk
- Department of Interfacial
Phenomena, Faculty of Chemistry, Maria Curie-Skłodowska University, Maria Curie-Skłodowska
Sq. 3, 20-031 Lublin, Poland
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12
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Szymczyk K, Jańczuk B. Surface Tension of Polytetrafluoroethylene and Polymethyl Methacrylate under the Influence of the Fluorocarbon Surfactant Film. Ind Eng Chem Res 2012. [DOI: 10.1021/ie301653h] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Katarzyna Szymczyk
- Department of Interfacial Phenomena, Faculty
of Chemistry, Maria Curie-Skłodowska University, Maria Curie-Skłodowska Sq. 3, 20-031
Lublin, Poland
| | - Bronisław Jańczuk
- Department of Interfacial Phenomena, Faculty
of Chemistry, Maria Curie-Skłodowska University, Maria Curie-Skłodowska Sq. 3, 20-031
Lublin, Poland
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13
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May A, Pasc A, Stébé MJ, Gutiérrez JM, Porras M, Blin JL. Tailored jeffamine molecular tools for ordering mesoporous silica. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:9816-9824. [PMID: 22650907 DOI: 10.1021/la301413u] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Herein, we report the formation of organized mesoporous silica materials prepared from a novel nonionic gemini surfactant, myristoyl-end-capped Jeffamine, synthesized from a polyoxyalkyleneamine (ED900). The behavior of the modified Jeffamine in water was first investigated. A direct micellar phase (L(1)) and a hexagonal (H(1)) liquid crystal were found. The structure of the micelles was investigated from the SAXS and the analysis by generalized indirect Fourier transformation, which show that the particles are globular of core-shell type. The myristoyl chains, located at the ends of the amphiphile molecule, are assembled to form the core of the micelles and, as a consequence, the molecules are folded over on themselves. Mesoporous materials were then synthesized from the self-assembly mechanism. The recovered materials were characterized by SAXS measurements, nitrogen adsorption-desorption analysis, and transmission and scanning electron microscopy. The results clearly evidence that by modifying the synthesis parameters, such as the surfactant/silica precursor molar ratio and the hydrothermal conditions, one can control the size and the nanostructuring of the resulting material. It was observed that, the lower the temperature of the hydrothermal treatment, the better the mesopore ordering.
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Affiliation(s)
- A May
- Université de Lorraine, SRSMC, UMR7565, F-54506 Vandoeuvre-lès-Nancy cedex, France
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Blin J, Du N, Stébé M. Alcohols solubilization in a nonionic fluorinated surfactant based system: Effect on the mesoporous silica characteristics. J Colloid Interface Sci 2012; 373:34-45. [DOI: 10.1016/j.jcis.2011.08.082] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Revised: 08/29/2011] [Accepted: 08/30/2011] [Indexed: 11/17/2022]
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Michaux F, Blin JL, Teixeira J, Stébé MJ. Structural Investigation of Nonionic Fluorinated Micelles by SANS in Relation to Mesoporous Silica Materials. J Phys Chem B 2011; 116:261-8. [DOI: 10.1021/jp209853r] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Florentin Michaux
- Equipe Physico-chimie des Colloïdes, UMR SRSMC N° 7565, Université Nancy-1/CNRS Faculté des Sciences, BP 70239, F-54506 Vandoeuvre-les-Nancy cedex, France
| | - Jean-Luc Blin
- Equipe Physico-chimie des Colloïdes, UMR SRSMC N° 7565, Université Nancy-1/CNRS Faculté des Sciences, BP 70239, F-54506 Vandoeuvre-les-Nancy cedex, France
| | - José Teixeira
- Laboratoire Léon Brillouin (CEA/CNRS), CEA-Saclay, 91191 Gif-sur-Yvette Cedex, France
| | - Marie José Stébé
- Equipe Physico-chimie des Colloïdes, UMR SRSMC N° 7565, Université Nancy-1/CNRS Faculté des Sciences, BP 70239, F-54506 Vandoeuvre-les-Nancy cedex, France
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16
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May A, Stébé MJ, Gutiérrez JM, Blin JL. Coexistence of two kinds of fluorinated hydrogenated micelles as building blocks for the design of bimodal mesoporous silica with two ordered mesopore networks. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:14000-14004. [PMID: 22043901 DOI: 10.1021/la203753q] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A simple and effective route has been developed for the synthesis of bimodal (3.6 and 9.4 nm) mesoporous silica materials that have two ordered interconnected pore networks. Mesostructures have been prepared through the self-assembly mechanism by using a mixture of polyoxyethylene fluoroalkyl ether and triblock copolymer as building blocks. The investigation of the R(F)(8)(EO)(9)/P123/water phase diagram shows that in the considered surfactant range of concentrations the system is micellar (L(1)). DLS measurements indicate that this micellar phase is composed of two types of micelles; the size of the first one at around 7.6 nm corresponds unambiguously to the pure fluorinated micelles. The second type of micelles at higher diameter consists of fluorinated micelles that have accommodated a weak fraction of P123 molecules. Thus, in this study the bimodal mesoporous silica is really templated by two kinds of micelles.
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Affiliation(s)
- A May
- Chemical Engineering Department, Chemistry Faculty, Universitat de Barcelona, Martí i Franquès 1-11, 08028 Barcelona, Catalonia, Spain
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17
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Steiner E, Bouguet-Bonnet S, Blin JL, Canet D. Water behavior in mesoporous materials as studied by NMR relaxometry. J Phys Chem A 2011; 115:9941-6. [PMID: 21793571 DOI: 10.1021/jp205456g] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Water in mesoporous materials possessing a two-dimensional hexagonal structure has been studied by the variation of its NMR longitudinal relaxation time T(1) as a function of the static magnetic field value, or equivalently of the NMR measurement frequency. This technique, dubbed relaxometry, has been applied from 5 kHz (measurement frequency) up to 400 MHz with various instruments including a variable-field spectrometer operating between 8 and 90 MHz. Moreover, the range 0-5 kHz could be investigated by transverse relaxation, T(2) denoting the corresponding relaxation time, and relaxation in the rotating frame, T(1ρ) denoting the corresponding relaxation time. Measurements of proton relaxation rates (inverse of relaxation times) have been performed with H(2)O and HOD (residual protons of heavy water) at water volumes of 80%, 60%, and 40% relative to the porous volume. Comparison between H(2)O and HOD shows clearly that, above 1 MHz where both sets of data are superposed, relaxation is purely intermolecular and due to paramagnetic relaxation (dipolar interactions of water protons with unpaired electrons of paramagnetic entities). Below 1 MHz, it is possible to subtract the intermolecular contribution (given by HOD data) from H(2)O data so that one is left with intramolecular relaxation which is solely due to water reorientational motions. The analysis of these low-frequency data (in terms of Lorentzian functions) reveals two types of water within the pores: one interacting strongly with the surface and the other corresponding to a second layer. High-frequency data, which arise from paramagnetic relaxation, exhibit again two types of water. Due to their correlation times, one type is assigned to relatively free water within the pores while the other type corresponds to bulk (interparticular) water. Their proportions, given as a function of the volume fraction, are consistent with the above assignments.
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Affiliation(s)
- Emilie Steiner
- Méthodologie RMN (CRM2, UMR 7036 CNRS), Nancy-Université, BP 70239, 54506 Vandoeuvre-lès-Nancy Cedex, France
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18
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Hawley AM, Edler KJ, Roser SJ. Mesoporous titanium dioxide films using partially fluorinated surfactant templates in ethanol. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1jm10963d] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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JIANG H, DAI H, XIA Y, HE H. Synthesis and Characterization of Wormhole-Like Mesoporous SnO<SUB>2</SUB> with High Surface Area. CHINESE JOURNAL OF CATALYSIS 2010. [DOI: 10.3724/sp.j.1088.2010.90914] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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20
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NMR relaxometry: Spin lattice relaxation times in the laboratory frame versus spin lattice relaxation times in the rotating frame. Chem Phys Lett 2010. [DOI: 10.1016/j.cplett.2010.06.064] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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21
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Preparation and characterization of porous silica templated by a nonionic fluorinated systems. Colloids Surf A Physicochem Eng Asp 2010. [DOI: 10.1016/j.colsurfa.2009.12.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Henderson MJ, Zimny K, Blin JL, Delorme N, Bardeau JF, Gibaud A. TiO2 thin films self-assembled with a partly fluorinated surfactant template. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:1124-1129. [PMID: 19754061 DOI: 10.1021/la902224t] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
New TiO(2) films have been self-assembled on solid substrate by dip-coating using TiCl(4) as the titanium source and the partly fluorinated surfactant F(CF(2))(8)C(2)H(4)(OC(2)H(4))(9)OH as the liquid crystal template. By control over the dip-withdrawal speed, film thicknesses from a minimum of 43 nm were produced with rms roughnesses of 0.5-0.7 nm. The films were characterized by X-ray reflectivity, grazing incidence small-angle X-ray scattering, atomic force microscopy, contact angle measurements, and Raman spectroscopy. Their GI-SAXS patterns are characteristic of a 2-D hexagonal structure in which tubular rods of the fluorinated surfactant are packed hexagonally and aligned parallel to the substrate. Reflectivity and contact angle measurements of the as-prepared film indicate that a low-density hydrophilic TiO(2) surface presents to the air.
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Affiliation(s)
- Mark J Henderson
- Laboratoire de Physique de l'Etat Condensé, UMR CNRS 6087, Université du Maine, 72085 Le Mans Cedex 09, France
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Zimny K, Ghanbaja J, Carteret C, Stébé MJ, Blin JL. Highly ordered mesoporous titania with semi crystalline framework templated by large or small nonionic surfactants. NEW J CHEM 2010. [DOI: 10.1039/c0nj00488j] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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24
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Synthesis and Characterization of Wormhole-Like Mesoporous SnO2 with High Surface Area. CHINESE JOURNAL OF CATALYSIS 2010. [DOI: 10.1016/s1872-2067(09)60052-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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25
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Pelaez M, de la Cruz AA, Stathatos E, Falaras P, Dionysiou DD. Visible light-activated N-F-codoped TiO2 nanoparticles for the photocatalytic degradation of microcystin-LR in water. Catal Today 2009. [DOI: 10.1016/j.cattod.2008.12.022] [Citation(s) in RCA: 224] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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26
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Zimny K, Blin J, Stébé M. Influence of methanol on the phase behavior of nonionic fluorinated surfactant: Relation to the structure of mesoporous silica materials. J Colloid Interface Sci 2009; 330:456-62. [DOI: 10.1016/j.jcis.2008.10.076] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2008] [Revised: 10/27/2008] [Accepted: 10/28/2008] [Indexed: 11/24/2022]
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27
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Michaux F, Blin JL, Stébé MJ. Nonionic Fluorinated−Hydrogenated Surfactants for the Design of Mesoporous Silica Materials. J Phys Chem B 2008; 112:11950-9. [DOI: 10.1021/jp8035378] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- F. Michaux
- Equipe Physico-chimie des Colloïdes, UMR SRSMC N° 7565 Université Henri Poincaré - Nancy 1/CNRS, Faculté des Sciences, BP 239, F-54506 Vandoeuvre-les-Nancy cedex
| | - J. L. Blin
- Equipe Physico-chimie des Colloïdes, UMR SRSMC N° 7565 Université Henri Poincaré - Nancy 1/CNRS, Faculté des Sciences, BP 239, F-54506 Vandoeuvre-les-Nancy cedex
| | - M. J. Stébé
- Equipe Physico-chimie des Colloïdes, UMR SRSMC N° 7565 Université Henri Poincaré - Nancy 1/CNRS, Faculté des Sciences, BP 239, F-54506 Vandoeuvre-les-Nancy cedex
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Michaux F, Blin JL, Stébé MJ. Relation between the lower consolute boundary and the structure of mesoporous silica materials. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:1044-1052. [PMID: 18161998 DOI: 10.1021/la7029104] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
In this study, we have shed some light on the relation between the position of the lower consolute boundary of various nonionic surfactants in water and the structure of the mesoporous silica materials synthesized from these surfactants-based systems. In the first part, the lower consolute boundary was shifted by adding salts. Depending on the features of the phase diagram, we have looked for either a salting out or a salting in effect. Mesoporous materials were prepared from a micellar solution of the investigated surfactants. Results clearly evidenced that the cooperative self-assembly mechanism is not favored if the lower consolute boundary is not shifted toward high temperatures. Moreover, the higher the difference between the phase separation temperature and the temperature at which the silica precursor is added to the surfactant solution, the better the mesopore ordering is. In the second part, this tendency has been confirmed by using a hydrogenated surfactant as additive.
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Affiliation(s)
- F Michaux
- Equipe Physico-chimie des Colloïdes, UMR SRSMC No. 7565, Université Henri Poincaré-Nancy 1/CNRS, Faculté des Sciences, BP 239, F-54506 Vandoeuvre-les-Nancy cedex
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29
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Sharma SC, Rodríguez-Abreu C, Shrestha LK, Aramaki K. Short haired wormlike micelles in mixed nonionic fluorocarbon surfactants. J Colloid Interface Sci 2007; 314:223-9. [PMID: 17588597 DOI: 10.1016/j.jcis.2007.05.066] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2007] [Revised: 05/11/2007] [Accepted: 05/16/2007] [Indexed: 11/29/2022]
Abstract
We have studied the rheological behavior of viscoelastic wormlike micellar solution in a mixed system of nonionic fluorinated surfactants, perfluoroalkyl sulfonamide ethoxylate, C(8)F(17)SO(2)N(C(3)H(7))(CH(2)CH(2)O)(n)H abbreviated as C(8)F(17)EO(n) (n=10 and 20). Above critical micelle concentration, the surfactant, C(8)F(17)EO(20) forms small spherical micelles in water and the viscosity of the solution remains constant regardless of the shear rate, i.e., the solutions exhibit Newtonian behavior. However, upon successive addition of the C(8)F(17)EO(10) the viscosity of the solution increases and at certain C(8)F(17)EO(10) concentration, shear-thinning behavior is observed indicating the formation wormlike micelles. Contrary to what is expected, there is a viscosity increase with the addition of the hydrophilic C(8)F(17)EO(20) to C(8)F(17)EO(10) aqueous solutions at certain temperature and concentration, which could be attributed to an increase in rigidity of the surfactant layer and to the shifting of micellar branching to higher temperatures. The oscillatory-shear rheological behavior of the viscoelastic solution can be described by Maxwell model at low frequency. Small-angle X-ray scattering (SAXS) measurements confirmed the formation of small spherical micellar aggregates in the dilute aqueous C(8)F(17)EO(20) solution. The SAXS data shows the one-dimensional growth on the micellar size with increase in the C(8)F(17)EO(10) concentration. Thus, the present SAXS data supports the rheological data.
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Affiliation(s)
- Suraj Chandra Sharma
- Graduate School of Environment and Information Sciences, Yokohama National University, Tokiwadai 79-7, Hodogaya-ku, Yokohama 240-8501, Japan
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Investigation of the C16(EO)10/decane/water system for the design of porous silica materials. Colloids Surf A Physicochem Eng Asp 2007. [DOI: 10.1016/j.colsurfa.2007.05.031] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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31
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Meng X, Lu D, Tatsumi T. Synthesis of Mesoporous Silica Single Crystal SBA-16 by Fluorinated Surfactants with Short Carbon Chains. CHEM LETT 2007. [DOI: 10.1246/cl.2007.670] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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32
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Rodríguez-Abreu C, Botta PM, Rivas J, Aramaki K, Quintela MAL. Mesostructured fluorocarbon–silica hybrid materials with a low dielectric constant. Colloids Surf A Physicochem Eng Asp 2007. [DOI: 10.1016/j.colsurfa.2006.11.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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33
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Michaux F, Blin JL, Stébé MJ. Design of ordered bimodal mesoporous silica materials by using a mixed fluorinated-hydrogenated surfactant-based system. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:2138-44. [PMID: 17279706 DOI: 10.1021/la063103p] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Mesoporous silica materials have been prepared using aqueous solutions of hydrogenated-fluorinated surfactant mixtures. The phase behavior of the C18H35(OC2H4)10-C6F15C2H4(OC2H4)11OH [RH18(EO)10-RF6(EO)11] mixture in aqueous solution was first established at the temperature at which the silica source is added, i.e., 20 or 40 degrees C. We have delimited the different phase domains. Concerning the mesostructured silica, whatever the temperature at which the silica source is added, mesoporous material with a hexagonal array of their channel is formed via a cooperative templating mechanism (CTM), if the content of RF6(EO)11 in the surfactant mixture is lower than 50%. Moreover, when the silica source is added at 40 degrees C, the recovered materials exhibit a bimodal pore size distribution. The appearance of this bimodality has been related to the coexistence of hydrogenated micelles with fluorinated wormlike micelles. By contrast, the bimodality is not observed when the silica source is added at 20 degrees C.
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Affiliation(s)
- F Michaux
- Equipe Physico-chimie des Colloïdes, Faculté des Sciences, UMR SRSMC No. 7565, Université Henri Poincaré-Nancy 1/CNRS, BP 239, F-54506 Vandoeuvre-les-Nancy cedex, France
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34
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Synthesis and characterization of wormhole-like mesoporous Ce0.6Zr0.35Y0.05O2 solid solutions. CHINESE SCIENCE BULLETIN-CHINESE 2007. [DOI: 10.1007/s11434-007-0013-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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35
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Bleta R, Blin JL, Stébé MJ. Solubilization of Various Fluorocarbons in a Fluorinated Surfactant/Water System: Relation with the Design of Porous Materials. J Phys Chem B 2006; 110:23547-56. [PMID: 17107210 DOI: 10.1021/jp0644199] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have investigated the phase behavior of the R(F)(7)(EO)(8) surfactant in water as well as the effect of the solubilization of various fluorocarbons in this system. Results show that the cloud point (CP) curve is shifted to high temperatures upon addition of fluorocarbons, following the sequence 1-bromo-perfluorooctane (PFOB) < perfluorodecalin (PFD) < perfluorooctane (PFO). The values of the phase inversion temperature (PIT) associated with these systems increase in the same order: PFOB approximately 65 degrees C, PFD approximately 82 degrees C, and PFO > 90 degrees C. Starting from these systems, we have prepared mesoporous and hierarchical porous materials. The formation of the ordered mesoporous materials has been related to the CP curve. Indeed, our results show that mesoporous materials with a high degree of ordering are obtained from systems whose CP curve is shifted toward high temperatures. We have also correlated the formation of the hierarchical porous silica to the PIT. It appears that the design of macro-mesoporous materials is favored with systems that exhibit a high value of the PIT.
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Affiliation(s)
- R Bleta
- Equipe Physico-chimie des Colloïdes, UMR SRSMC N(o) 7565 Université Nancy-1, CNRS, Faculté des Sciences, BP 239, F-54506 Vandoeuvre-les-Nancy Cedex
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36
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Blin JL, Henzel N, Stébé MJ. Mixed fluorinated–hydrogenated surfactant-based system: Preparation of ordered mesoporous materials. J Colloid Interface Sci 2006; 302:643-50. [PMID: 16872623 DOI: 10.1016/j.jcis.2006.07.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2006] [Revised: 06/30/2006] [Accepted: 07/04/2006] [Indexed: 11/20/2022]
Abstract
We have investigated a mixed fluorinated-hydrogenated surfactant-based system [C8F17C2H4(OC2H4)9-C12H25(OC2H4)8] in water. The phase diagram exhibits that the micellar domain can be divided into three parts: above 80 wt% of water both hydrogenated and fluorinated surfactants are completely miscible and they formed mixed micelles in all proportion. When the water concentration is decreased from 80 to 60 wt% a gap of miscibility appears and two micellar zones, one fluorocarbon-rich micelles and one hydrocarbon-rich micelles are observed. The liquid crystal domain is composed of one fluorocarbon-rich (H(F)(1)) and one hydrocarbon-rich (H(H)(1)) hexagonal phase. The hydrophobic radius and the cross-sectional area remain constant in the H(H)(1) and in the H(F)(1) domains. Moreover, SAXS measurements proved that the hydrophobic chains in the liquid crystal phases adopt rather an extended conformation. Then the mixture of surfactants was used as template for the preparation of mesoporous materials. Mesostructured silicas with a well hexagonal array of their channels were prepared via a cooperative templating mechanism (CTM), if the loading of fluorinated surfactant is larger than 50%. Decreasing the proportion of the fluorinated amphiphile in the mixture leads to the formation of mesoporous silica with a disordered structure. In this case the channel arrangement is no longer governed by the fluorinated surfactant but by the hydrogenated one.
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Affiliation(s)
- J L Blin
- Equipe Physico-chimie des Colloïdes UMR SRSMC No. 7565 Université Henri Poincaré - Nancy 1/CNRS, Faculté des Sciences, BP 239, F-54506 Vandoeuvre-les-Nancy cedex, France
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Blin JL, Bleta R, Stébé MJ. Cloud point curve of nonionic surfactant related to the structures of mesoporous materials. J Colloid Interface Sci 2006; 300:765-73. [PMID: 16677667 DOI: 10.1016/j.jcis.2006.04.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2006] [Revised: 03/29/2006] [Accepted: 04/02/2006] [Indexed: 11/15/2022]
Abstract
We have investigated the phase behavior of a fluorinated surfactant R(7)(F)(EO)(7) in water. The cloud point is situated at 19 degrees C for 2 wt% of surfactant. Using this surfactant, mesoporous materials have been synthesized with micellar solution prepared either at 10 degrees C (below the cloud point) or at 40 degrees C (above the cloud point). Results show that whatever the syntheses conditions, only wormhole-like structure is recovered. The effect of perfluorodecalin addition on the fluorinated surfactant/water system was also investigated. Swollen micelles, microemulsion, and lamellar (L(alpha)) liquid crystals were identified. When perfluorodecalin is added, the cloud point is shifted toward higher temperature. As regards the mesoporous syntheses, perfluorodecalin plays a dual role. First, incorporation of perfluorodecalin leads to the formation of well ordered materials. Secondly, the pore size enlargement occurs when perfluorodecalin is added. Our results evidence that the ratio between the volume of the hydrophilic headgroup (V(H)) and the hydrophobic part (V(L)) of the surfactant is not an efficiency parameter to explain the ordering improvement of mesoporous materials and that we should rather consider the existence of the cloud point curve, which disturbs the cooperative templating mechanism (CTM).
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Affiliation(s)
- J L Blin
- Equipe Physico-Chimie des Colloïdes, UMR SRSMC 7565, Université Henri Poincaré-Nancy 1/CNRS, Faculté des Sciences, BP 239, F-54506 Vandoeuvre-les-Nancy cedex, France
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38
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Sharma SC, Kunieda H, Esquena J, Rodríguez Abreu C. Phase behavior and preparation of mesoporous silica in aqueous mixtures of fluorinated surfactant and hydrophobic fluorinated polymer. J Colloid Interface Sci 2006; 299:297-304. [PMID: 16480734 DOI: 10.1016/j.jcis.2006.01.040] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2005] [Revised: 01/19/2006] [Accepted: 01/19/2006] [Indexed: 11/19/2022]
Abstract
The phase behavior and formation of self-assemblies in the ternary water/fluorinated surfactant (C(8)F(17)EO(10))/hydrophobic fluorinated polymer (C(3)F(6)O)(n)COOH system and the application of those assemblies in the preparation of mesostructured silica have been investigated by means of phase study, small angle X-ray scattering, and rheology. Hexagonal (H(1)), bicontinuous cubic (V(1)) with Ia3d symmetry, and polymer rich lamellar (L(alpha)(')) are observed in the ternary diagram. C(8)F(17)EO(10) molecules are dissolved in polymer rich aggregates, whereas (C(3)F(6)O)(n)COOH molecules are practically insoluble in the surfactant lamellar phase due to packing restrictions. Hence, two types of lamellar phases exist: one with surfactant rich (L(alpha)) and the other with polymer rich (L(alpha)(')) in the water/C(8)F(17)EO(10)/(C(3)F(6)O)(n)COOH system. As suggested by rheological measurements, worm-like micelles are present in C(8)F(17)EO(10) aqueous solutions but a rod-sphere transition takes place by solubilization of (C(3)F(6)O)(n)COOH. C(8)F(17)EO(10) acts as a structure directing agent for the preparation of hexagonal mesoporous silica by the precipitation method. The addition of (C(3)F(6)O)(n)COOH induces the formation of larger but disordered pores.
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Affiliation(s)
- Suraj Chandra Sharma
- Graduate School of Environment and Information Sciences, Yokohama National University, Tokiwadai 79-7, Hodogaya-ku, Yokohama 240-8501, Japan
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39
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Di Y, Meng X, Wang L, Li S, Xiao FS. Ultralow temperature synthesis of ordered hexagonal smaller supermicroporous silica using semifluorinated surfactants as template. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2006; 22:3068-72. [PMID: 16548559 DOI: 10.1021/la0521342] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Ordered hexagonal smaller supermicroporous silica (JLU-14L and JLU-11L) has been successfully synthesized at ultralow temperature (0 approximately -20 degrees C) by semifluorinated surfactants, which is extensively investigated by X-ray diffraction, N2 adsorption, and transmission electron microscopy. X-ray diffraction shows that the peak intensity of the samples increases with decreasing synthesis temperatures in the range of 0 approximately -20 degrees C, indicating that the ordering of porous silica improves with decreasing synthesis temperature. N2 adsorption/ desorption isotherms show that JLU-14L has both ordered smaller hexagonal supermicropores (1.27 and 1.28 nm) and disordered micropores (0.67 nm). Such hierarchically porous materials with micro/supermicroporosity should be potentially important for fast diffusion of reactants and products in catalytic reactions. The ultralow temperature synthesis is a crucial factor for the formation of ordered smaller supermicropores and the control of microporosity in JLU-14L.
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Affiliation(s)
- Yan Di
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry and Department of Chemistry, Jilin University, Changchun 130012, PR China
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40
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Gov N, Borukhov I, Goldfarb D. Morphological transitions during the formation of templated mesoporous materials: theoretical modeling. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2006; 22:605-14. [PMID: 16401108 DOI: 10.1021/la052272r] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
We put forward a theoretical model for the morphological transitions of templated mesoporous materials. These materials consist of a mixture of surfactant molecules and inorganic compounds which evolve dynamically upon mixing to form different morphologies depending on the composition and conditions at which mixing occurs. Our theoretical analysis is based on the assumption that adsorption of the inorganic compounds onto mesoscopic assemblies of surfactant molecules changes the effective interactions between the surfactant molecules, consequently lowering the spontaneous curvature of the surfactant layer and inducing morphological changes in the system. On the basis of a mean field phase diagram, we are able to follow the trajectories of the system starting with different initial conditions, and predict the final morphology of the product. In a typical scenario, the reduction in the spontaneous curvature leads first to a smooth transition from compact spherical micelles to elongated worm-like micelles. In the second stage, the layer of inorganic material coating the micelles gives rise to attractive inter-micellar interactions that eventually induce a collapse of the system into a closely packed hexagonal array of coated cylinders. Other pathways may lead to different structures including disordered bicontinuous and ordered cubic phases. The model is in good qualitative agreement with experimental observations.
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Affiliation(s)
- N Gov
- Department of Chemical Physics, The Weizmann Institute of Science, P.O. Box 26, Rehovot, Israel 76100.
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41
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Xing R, Rankin SE. Three-Stage Multilayer Formation Kinetics during Adsorption of an Anionic Fluorinated Surfactant onto Germanium. 1. Concentration Effect. J Phys Chem B 2005; 110:295-304. [PMID: 16471536 DOI: 10.1021/jp0549069] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The adsorption of tetraethylammonium perfluorooctylsulfonate (TEA-FOS) from aqueous solution onto hydroxylated germanium is studied using in situ polarized attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). The adsorption is monitored at a series of bulk solution concentrations spanning from well below to above the critical micelle concentration (CMC; 1.0 mM). The kinetics of adsorption is followed by monitoring the intensity of the fluorocarbon bands. The orientation of the fluorocarbon director with respect to the germanium surface is determined by circular dichroism measurements of CF2 stretching bands. At bulk concentrations ranging from 10% of the CMC to at least 500% of the CMC, the adsorption occurs in an unusual sequence of three stages. Initially, rapid adsorption occurs within 200 min, leading to coverage of a monolayer or less. A long period of slow adsorption follows, during which we hypothesize that surfactant molecules form clusters, some of which serve as nuclei for multilayer growth. This stage concludes suddenly with an acceleration in the rate of adsorption, which eventually leads to multilayer formation. Because this is an anionic surfactant adsorbing onto a negatively charged surface at pH 6, the tetraethylammonium ions must mediate the interactions between the surfactant headgroups and the surface. The dichroism measurements show that TEA-FOS is initially oriented randomly or somewhat parallel to the surface, but over time adopts an orientation somewhat normal to the surface. This behavior is consistent with initial adsorption at isolated sites, followed by aggregation into isotropic admicelles, and finally growth into flattened admicelles. The sudden onset of accelerated adsorption can be explained either by autoaccelerating adsorption or nucleation and growth of a hydrophobic multilayer structure.
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Affiliation(s)
- Rong Xing
- Chemical and Materials Engineering Department, University of Kentucky, 177 Anderson Hall, Lexington, Kentucky 40506-0046, USA
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42
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Tan B, Vyas SM, Lehmler HJ, Knutson BL, Rankin SE. Unusual Dependence of Particle Architecture on Surfactant Concentration in Partially Fluorinated Decylpyridinium Templated Silica. J Phys Chem B 2005; 109:23225-32. [PMID: 16375286 DOI: 10.1021/jp054219h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A series of porous silica particles is prepared with different concentrations of the fluorinated cationic surfactant 1-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10)-heptadecafluorodecyl)pyridinium chloride (HFDePC) to trace the changes in pore structure and particle morphology as the surfactant concentration increases. At the lowest concentration studied (1.5 mmol/L), the product consists of small round particles with close-packed cylindrical mesopores. As the HFDePC concentration increases, macroporous voids are introduced to create multi-chambered hollow particles with mesoporous walls. With a still higher concentration of HFDePC the macropore volume decreases, and elongated, tactoid-like nanoparticles are formed with random mesh-phase pores oriented with silica layers perpendicular to the main axis of the particles. Further increasing the concentration of HFDePC eventually leads to the formation of round particles with disordered pores. These changes are consistent with increasing HFDePC concentration favoring increasingly oblate or disklike micelles. The process of forming the elongated particles with random mesh-phase structure is investigated by TEM of chilled and dried samples. The results indicate that the oriented tactoid-like structure forms spontaneously within 2 min by co-assembly of silica and HFDePC rather than by preferred growth perpendicular to the layers. The particle shape and layer orientation are consistent with what would be expected for a liquid-crystal particle with orientation-dependent surface tension. Finally, we compare samples prepared with a high HFDePC and with good or poor mixing. With inadequate mixing, a gel layer forms at the top of the sample which is composed of elongated mesoporous particles with a thick coating of microporous silica. The lower particulate phase contains small disordered particles similar to those obtained in a well-mixed sample. Presumably, the structure of the upper layer results from initial immiscibility of the precursor and slow diffusion of silicates out of the gel.
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Affiliation(s)
- Bing Tan
- Chemical and Materials Engineering Department, University of Kentucky, 177 Anderson Hall, Lexington, Kentucky 40506-0046, USA
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43
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Tan B, Dozier A, Lehmler HJ, Knutson BL, Rankin SE. Elongated silica nanoparticles with a mesh phase mesopore structure by fluorosurfactant templating. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:6981-6984. [PMID: 15301475 DOI: 10.1021/la049474s] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Mesoporous silica materials with pore structures such as 2D hexagonal close packed, bicontinuous cubic, lamellar, sponge, wormhole-like, and rectangular have been made by using surfactant templating sol-gel processes. However, there are still some "intermediate" phases, in particular mesh phases, that are formed by surfactants but which have not been made into analogous silica pore structures. Here, we describe the one-step synthesis of mesoporous silica with a mesh phase pore structure. The cationic fluorinated surfactant 1,1,2,2-tetrahydroperfluorodecylpyridinium chloride (HFDePC) is used as the template. Like many fluorinated surfactants, HFDePC forms intermediate phases in water (including a mesh phase) over a wider range of compositions than do hydrocarbon surfactants. The materials produced by this technique are novel elongated particles in which the layers of the mesh phase are oriented orthogonal to the main axis of the particles.
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Affiliation(s)
- Bing Tan
- Chemical and Materials Engineering Department, University of Kentucky, 177 Anderson Hall, Lexington, Kentucky 40506-0046, USA
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Blin JL, Stébé MJ. Perfluorodecalin Incorporation in Fluorinated Surfactant−Water System: Tailoring of Mesoporous Materials Pore Size. J Phys Chem B 2004. [DOI: 10.1021/jp049379s] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- J. L. Blin
- Equipe Physico-chimie des Colloïdes, UMR SRSMC No. 7565, Université Nancy-1/CNRS, Faculté des Sciences, BP 239, F-54506 Vandoeuvre-les-Nancy Cedex, France
| | - M. J. Stébé
- Equipe Physico-chimie des Colloïdes, UMR SRSMC No. 7565, Université Nancy-1/CNRS, Faculté des Sciences, BP 239, F-54506 Vandoeuvre-les-Nancy Cedex, France
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