1
|
Le Brun AP, Gilbert EP. Advances in sample environments for neutron scattering for colloid and interface science. Adv Colloid Interface Sci 2024; 327:103141. [PMID: 38631095 DOI: 10.1016/j.cis.2024.103141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 03/27/2024] [Accepted: 03/27/2024] [Indexed: 04/19/2024]
Abstract
This review describes recent advances in sample environments across the full complement of applicable neutron scattering techniques to colloid and interface science. Temperature, pressure, flow, tensile testing, ultrasound, chemical reactions, IR/visible/UV light, confinement, humidity and electric and magnetic field application, as well as tandem X-ray methods, are all addressed. Consideration for material choices in sample environments and data acquisition methods are also covered as well as discussion of current and potential future use of machine learning and artificial intelligence.
Collapse
Affiliation(s)
- Anton P Le Brun
- Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organisation (ANSTO), New Illawarra Road, Lucas Heights, NSW 2234, Australia
| | - Elliot Paul Gilbert
- Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organisation (ANSTO), New Illawarra Road, Lucas Heights, NSW 2234, Australia.
| |
Collapse
|
2
|
Busch C, Nagy B, Stöcklin A, Gutfreund P, Dahint R, Ederth T. A mobile setup for simultaneous and in situ neutron reflectivity, infrared spectroscopy, and ellipsometry studies. Rev Sci Instrum 2022; 93:114102. [PMID: 36461462 DOI: 10.1063/5.0118329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 10/08/2022] [Indexed: 06/17/2023]
Abstract
Neutron reflectivity at the solid/liquid interface offers unique opportunities for resolving the structure-function relationships of interfacial layers in soft matter science. It is a non-destructive technique for detailed analysis of layered structures on molecular length scales, providing thickness, density, roughness, and composition of individual layers or components of adsorbed films. However, there are also some well-known limitations of this method, such as the lack of chemical information, the difficulties in determining large layer thicknesses, and the limited time resolution. We have addressed these shortcomings by designing and implementing a portable sample environment for in situ characterization at neutron reflectometry beamlines, integrating infrared spectroscopy under attenuated total reflection for determination of molecular entities and their conformation, and spectroscopic ellipsometry for rapid and independent measurement of layer thicknesses and refractive indices. The utility of this combined setup is demonstrated by two projects investigating (a) pH-dependent swelling of polyelectrolyte layers and (b) the impact of nanoparticles on lipid membranes to identify potential mechanisms of nanotoxicity.
Collapse
Affiliation(s)
- Christian Busch
- Applied Physical Chemistry, Institute for Physical Chemistry, Heidelberg University, Im Neuenheimer Feld 253, 69120 Heidelberg, Germany
| | - Béla Nagy
- Division of Biophysics and Bioengineering, Department of Physics, Chemistry and Biology (IFM), Linköping University, 581 83 Linköping, Sweden
| | - Andreas Stöcklin
- Applied Physical Chemistry, Institute for Physical Chemistry, Heidelberg University, Im Neuenheimer Feld 253, 69120 Heidelberg, Germany
| | - Philipp Gutfreund
- Institut Laue-Langevin, 71 Avenue des Martyrs, CS 20156, 38042 Grenoble Cedex 9, France
| | - Reiner Dahint
- Applied Physical Chemistry, Institute for Physical Chemistry, Heidelberg University, Im Neuenheimer Feld 253, 69120 Heidelberg, Germany
| | - Thomas Ederth
- Division of Biophysics and Bioengineering, Department of Physics, Chemistry and Biology (IFM), Linköping University, 581 83 Linköping, Sweden
| |
Collapse
|
3
|
Liu X, Counil C, Shi D, Mendoza-Ortega EE, Vela-Gonzalez AV, Maestro A, Campbell RA, Krafft MP. First quantitative assessment of the adsorption of a fluorocarbon gas on phospholipid monolayers at the air/water interface. J Colloid Interface Sci 2021; 593:1-10. [DOI: 10.1016/j.jcis.2021.02.073] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 02/15/2021] [Accepted: 02/16/2021] [Indexed: 12/19/2022]
|
4
|
Woden B, Skoda M, Hagreen M, Pfrang C. Night-Time Oxidation of a Monolayer Model for the Air–Water Interface of Marine Aerosols—A Study by Simultaneous Neutron Reflectometry and in Situ Infra-Red Reflection Absorption Spectroscopy (IRRAS). Atmosphere 2018; 9:471. [DOI: 10.3390/atmos9120471] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
This paper describes experiments on the ageing of a monolayer model for the air–water interface of marine aerosols composed of a typical glycolipid, galactocerebroside (GCB). Lipopolysaccharides have been observed in marine aerosols, and GCB is used as a proxy for these more complex lipopolysaccharides. GCB monolayers are investigated as pure films, as mixed films with palmitic acid, which is abundant in marine aerosols and forms a stable attractively mixed film with GCB, particularly with divalent salts present in the subphase, and as mixed films with palmitoleic acid, an unsaturated analogue of palmitic acid. Such mixed films are more realistic models of atmospheric aerosols than simpler single-component systems. Neutron reflectometry (NR) has been combined in situ with Fourier transform infra-red reflection absorption spectroscopy (IRRAS) in a pioneering analysis and reaction setup designed by us specifically to study mixed organic monolayers at the air–water interface. The two techniques in combination allow for more sophisticated observation of multi-component monolayers than has previously been possible. The structure at the air–water interface was also investigated by complementary Brewster angle microscopy (BAM). This study looks specifically at the oxidation of the organic films by nitrate radicals (NO3•), the key atmospheric oxidant present at night. We conclude that NO3• oxidation cannot fully remove a cerebroside monolayer from the surface on atmospherically relevant timescales, leaving its saturated tail at the interface. This is true for pure and salt water subphases, as well as for single- and two-component films. The behaviour of the unsaturated tail section of the molecule is more variable and is affected by interactions with co-deposited species. Most surprisingly, we found that the presence of CaCl2 in the subphase extends the lifetime of the unsaturated tail substantially—a new explanation for longer residence times of materials in the atmosphere compared to lifetimes based on laboratory studies of simplified model systems. It is thus likely that aerosols produced from the sea-surface microlayer at night will remain covered in surfactant molecules on atmospherically relevant timescales with impact on the droplet’s surface tension and on the transport of chemical species across the air–water interface.
Collapse
|
6
|
Pfrang C, Rastogi K, Cabrera-Martinez ER, Seddon AM, Dicko C, Labrador A, Plivelic TS, Cowieson N, Squires AM. Complex three-dimensional self-assembly in proxies for atmospheric aerosols. Nat Commun 2017; 8:1724. [PMID: 29170428 PMCID: PMC5701067 DOI: 10.1038/s41467-017-01918-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Accepted: 10/25/2017] [Indexed: 01/23/2023] Open
Abstract
Aerosols are significant to the Earth’s climate, with nearly all atmospheric aerosols containing organic compounds that often contain both hydrophilic and hydrophobic parts. However, the nature of how these compounds are arranged within an aerosol droplet remains unknown. Here we demonstrate that fatty acids in proxies for atmospheric aerosols self-assemble into highly ordered three-dimensional nanostructures that may have implications for environmentally important processes. Acoustically trapped droplets of oleic acid/sodium oleate mixtures in sodium chloride solution are analysed by simultaneous synchrotron small-angle X-ray scattering and Raman spectroscopy in a controlled gas-phase environment. We demonstrate that the droplets contained crystal-like lyotropic phases including hexagonal and cubic close-packed arrangements of spherical and cylindrical micelles, and stacks of bilayers, whose structures responded to atmospherically relevant humidity changes and chemical reactions. Further experiments show that self-assembly reduces the rate of the reaction of the fatty acid with ozone, and that lyotropic-phase formation also occurs in more complex mixtures more closely resembling compositions of atmospheric aerosols. We suggest that lyotropic-phase formation likely occurs in the atmosphere, with potential implications for radiative forcing, residence times and other aerosol characteristics. Nearly all atmospheric aerosols contain surface-active organic compounds; however, the nature of how they arrange remains poorly understood. Here, the authors show that fatty acids in atmospheric aerosol proxies self-assemble into highly ordered, viscous 3D nanostructures that undergo changes upon exposure to humidity and ozone.
Collapse
Affiliation(s)
- C Pfrang
- Department of Chemistry, University of Reading, Whiteknights Campus, PO Box 224, Reading, RG6 6AD, UK.
| | - K Rastogi
- Department of Chemistry, University of Reading, Whiteknights Campus, PO Box 224, Reading, RG6 6AD, UK
| | - E R Cabrera-Martinez
- Department of Chemistry, University of Reading, Whiteknights Campus, PO Box 224, Reading, RG6 6AD, UK
| | - A M Seddon
- H.H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol, BS8 1TL, UK.,Bristol Centre for Functional Nanomaterials, H.H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol, BS8 1TL, UK
| | - C Dicko
- Pure and Applied Biochemistry, Chemical Center, University of Lund, Naturvetarvägen 14, 22241, Lund, Sweden
| | - A Labrador
- MAX IV Laboratory, University of Lund, PO Box 188, 22100, Lund, Sweden
| | - T S Plivelic
- MAX IV Laboratory, University of Lund, PO Box 188, 22100, Lund, Sweden
| | - N Cowieson
- Diamond Light Source, Harwell Science & Innovation Campus, Didcot, OX11 0DE, UK
| | - A M Squires
- Department of Chemistry, University of Reading, Whiteknights Campus, PO Box 224, Reading, RG6 6AD, UK. .,Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK.
| |
Collapse
|
7
|
Skoda MWA, Thomas B, Hagreen M, Sebastiani F, Pfrang C. Simultaneous neutron reflectometry and infrared reflection absorption spectroscopy (IRRAS) study of mixed monolayer reactions at the air–water interface. RSC Adv 2017. [DOI: 10.1039/c7ra04900e] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
Simultaneous neutron reflectometry and infrared spectroscopy can follow the oxidation of complex, realistic surfactant mixtures relevant for atmospheric chemistry.
Collapse
Affiliation(s)
- Maximilian W. A. Skoda
- ISIS Pulsed Neutron and Muon Source
- Science and Technology Facilities Council
- Rutherford Appleton Laboratory
- Harwell
- UK
| | - Benjamin Thomas
- ISIS Pulsed Neutron and Muon Source
- Science and Technology Facilities Council
- Rutherford Appleton Laboratory
- Harwell
- UK
| | | | | | | |
Collapse
|