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Woods EV, Kim SH, El-Zoka AA, Stephenson LT, Gault B. Scalable substrate development for aqueous sample preparation for atom probe tomography. J Microsc 2023. [PMID: 38115688 DOI: 10.1111/jmi.13255] [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: 07/13/2023] [Revised: 11/13/2023] [Accepted: 12/15/2023] [Indexed: 12/21/2023]
Abstract
Reliable and consistent preparation of atom probe tomography (APT) specimens from aqueous and hydrated biological specimens remains a significant challenge. One particularly difficult process step is the use of a focused ion beam (FIB) instrument for preparing the required needle-shaped specimen, typically involving a 'lift-out' procedure of a small sample of material. Here, two alternative substrate designs are introduced that enable using FIB only for sharpening, along with example APT datasets. The first design is a laser-cut FIB-style half-grid close to those used for transmission electron microscopy (TEM) that can be used in a grid holder compatible with APT pucks. The second design is a larger, standalone self-supporting substrate called a 'crown', with several specimen positions, which self-aligns in APT pucks, prepared by electrical discharge machining (EDM). Both designs are made nanoporous, to provide strength to the liquid-substrate interface, using chemical and vacuum dealloying. Alpha brass, a simple, widely available, lower-cost alternative to previously proposed substrates, was selected for this work. The resulting designs and APT data are presented and suggestions are provided to help drive wider community adoption.
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Affiliation(s)
- Eric V Woods
- Department Mikrostrukturphysik und Legierungsdesign, Max-Planck-Institut für Eisenforschung, Düsseldorf, Germany
| | - Se-Ho Kim
- Department Mikrostrukturphysik und Legierungsdesign, Max-Planck-Institut für Eisenforschung, Düsseldorf, Germany
- Department of Materials Science and Engineering, Korea University, Seoul, Republic of Korea
| | - Ayman A El-Zoka
- Department Mikrostrukturphysik und Legierungsdesign, Max-Planck-Institut für Eisenforschung, Düsseldorf, Germany
- Department of Materials, Royal School of Mines, Imperial College London, London, UK
| | - L T Stephenson
- Department Mikrostrukturphysik und Legierungsdesign, Max-Planck-Institut für Eisenforschung, Düsseldorf, Germany
- Australian Centre for Microscopy and Microanalysis, The University of Sydney, Sydney, New South Wales, Australia
| | - B Gault
- Department Mikrostrukturphysik und Legierungsdesign, Max-Planck-Institut für Eisenforschung, Düsseldorf, Germany
- Department of Materials, Royal School of Mines, Imperial College London, London, UK
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2
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Ahmadian A, Scheiber D, Zhou X, Gault B, Liebscher CH, Romaner L, Dehm G. Aluminum depletion induced by co-segregation of carbon and boron in a bcc-iron grain boundary. Nat Commun 2021; 12:6008. [PMID: 34650043 PMCID: PMC8516984 DOI: 10.1038/s41467-021-26197-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 09/13/2021] [Indexed: 12/02/2022] Open
Abstract
The local variation of grain boundary atomic structure and chemistry caused by segregation of impurities influences the macroscopic properties of polycrystalline materials. Here, the effect of co-segregation of carbon and boron on the depletion of aluminum at a Σ5 (3 1 0 )[0 0 1] tilt grain boundary in a α - Fe-4 at%Al bicrystal is studied by combining atomic resolution scanning transmission electron microscopy, atom probe tomography and density functional theory calculations. The atomic grain boundary structural units mostly resemble kite-type motifs and the structure appears disrupted by atomic scale defects. Atom probe tomography reveals that carbon and boron impurities are co-segregating to the grain boundary reaching levels of >1.5 at%, whereas aluminum is locally depleted by approx. 2 at.%. First-principles calculations indicate that carbon and boron exhibit the strongest segregation tendency and their repulsive interaction with aluminum promotes its depletion from the grain boundary. It is also predicted that substitutional segregation of boron atoms may contribute to local distortions of the kite-type structural units. These results suggest that the co-segregation and interaction of interstitial impurities with substitutional solutes strongly influences grain boundary composition and with this the properties of the interface.
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Affiliation(s)
- A Ahmadian
- Max-Planck-Institut fuer Eisenforschung GmbH, Düsseldorf, Germany.
| | - D Scheiber
- Materials Center Leoben GmbH, Leoben, Austria
| | - X Zhou
- Max-Planck-Institut fuer Eisenforschung GmbH, Düsseldorf, Germany
| | - B Gault
- Max-Planck-Institut fuer Eisenforschung GmbH, Düsseldorf, Germany
- Department of Materials, Royal School of Mines, Imperial College London, London, UK
| | - C H Liebscher
- Max-Planck-Institut fuer Eisenforschung GmbH, Düsseldorf, Germany
| | - L Romaner
- Materials Center Leoben GmbH, Leoben, Austria
- Montanuniversität Leoben, Leoben, Austria
| | - G Dehm
- Max-Planck-Institut fuer Eisenforschung GmbH, Düsseldorf, Germany
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3
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Schwarz TM, Dietrich CA, Ott J, Weikum EM, Lawitzki R, Solodenko H, Hadjixenophontos E, Gault B, Kästner J, Schmitz G, Stender P. 3D sub-nanometer analysis of glucose in an aqueous solution by cryo-atom probe tomography. Sci Rep 2021; 11:11607. [PMID: 34078953 PMCID: PMC8172843 DOI: 10.1038/s41598-021-90862-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [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: 02/26/2021] [Accepted: 05/18/2021] [Indexed: 11/23/2022] Open
Abstract
Atom Probe Tomography (APT) is currently a well-established technique to analyse the composition of solid materials including metals, semiconductors and ceramics with up to near-atomic resolution. Using an aqueous glucose solution, we now extended the technique to frozen solutions. While the mass signals of the common glucose fragments CxHy and CxOyHz overlap with (H2O)nH from water, we achieved stoichiometrically correct values via signal deconvolution. Density functional theory (DFT) calculations were performed to investigate the stability of the detected pyranose fragments. This paper demonstrates APT’s capabilities to achieve sub-nanometre resolution in tracing whole glucose molecules in a frozen solution by using cryogenic workflows. We use a solution of defined concentration to investigate the chemical resolution capabilities as a step toward the measurement of biological molecules. Due to the evaporation of nearly intact glucose molecules, their position within the measured 3D volume of the solution can be determined with sub-nanometre resolution. Our analyses take analytical techniques to a new level, since chemical characterization methods for cryogenically-frozen solutions or biological materials are limited.
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Affiliation(s)
- T M Schwarz
- Chair of Materials Physics, Institute for Materials Science, University of Stuttgart, Heisenbergstr. 3, 70569, Stuttgart, Germany
| | - C A Dietrich
- Institute for Theoretical Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
| | - J Ott
- Chair of Materials Physics, Institute for Materials Science, University of Stuttgart, Heisenbergstr. 3, 70569, Stuttgart, Germany
| | - E M Weikum
- Chair of Materials Physics, Institute for Materials Science, University of Stuttgart, Heisenbergstr. 3, 70569, Stuttgart, Germany
| | - R Lawitzki
- Chair of Materials Physics, Institute for Materials Science, University of Stuttgart, Heisenbergstr. 3, 70569, Stuttgart, Germany
| | - H Solodenko
- Chair of Materials Physics, Institute for Materials Science, University of Stuttgart, Heisenbergstr. 3, 70569, Stuttgart, Germany
| | - E Hadjixenophontos
- Chair of Materials Physics, Institute for Materials Science, University of Stuttgart, Heisenbergstr. 3, 70569, Stuttgart, Germany
| | - B Gault
- Max-Planck-Institut Für Eisenforschung, Max-Planck-Str. 1, 40237, Düsseldorf, Germany.,Department of Materials, Royal School of Mines, Imperial College, Prince Consort Road, London, SW7 2BP, UK
| | - J Kästner
- Institute for Theoretical Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
| | - G Schmitz
- Chair of Materials Physics, Institute for Materials Science, University of Stuttgart, Heisenbergstr. 3, 70569, Stuttgart, Germany
| | - P Stender
- Chair of Materials Physics, Institute for Materials Science, University of Stuttgart, Heisenbergstr. 3, 70569, Stuttgart, Germany.
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Zhou X, Mianroodi JR, Kwiatkowski da Silva A, Koenig T, Thompson GB, Shanthraj P, Ponge D, Gault B, Svendsen B, Raabe D. The hidden structure dependence of the chemical life of dislocations. Sci Adv 2021; 7:7/16/eabf0563. [PMID: 33863726 PMCID: PMC8051869 DOI: 10.1126/sciadv.abf0563] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 03/01/2021] [Indexed: 06/12/2023]
Abstract
Dislocations are one-dimensional defects in crystals, enabling their deformation, mechanical response, and transport properties. Less well known is their influence on material chemistry. The severe lattice distortion at these defects drives solute segregation to them, resulting in strong, localized spatial variations in chemistry that determine microstructure and material behavior. Recent advances in atomic-scale characterization methods have made it possible to quantitatively resolve defect types and segregation chemistry. As shown here for a Pt-Au model alloy, we observe a wide range of defect-specific solute (Au) decoration patterns of much greater variety and complexity than expected from the Cottrell cloud picture. The solute decoration of the dislocations can be up to half an order of magnitude higher than expected from classical theory, and the differences are determined by their structure, mutual alignment, and distortion field. This opens up pathways to use dislocations for the compositional and structural nanoscale design of advanced materials.
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Affiliation(s)
- X Zhou
- Max-Planck-Institut für Eisenforschung, 40237 Düsseldorf, Germany.
| | - J R Mianroodi
- Max-Planck-Institut für Eisenforschung, 40237 Düsseldorf, Germany.
- Material Mechanics, RWTH Aachen University, 52062 Aachen, Germany
| | | | - T Koenig
- Department of Metallurgical and Materials Engineering, The University of Alabama, Tuscaloosa, AL 35401, USA
| | - G B Thompson
- Department of Metallurgical and Materials Engineering, The University of Alabama, Tuscaloosa, AL 35401, USA
| | - P Shanthraj
- The Department of Materials, The University of Manchester, M13 9PL Manchester, UK
| | - D Ponge
- Max-Planck-Institut für Eisenforschung, 40237 Düsseldorf, Germany
| | - B Gault
- Max-Planck-Institut für Eisenforschung, 40237 Düsseldorf, Germany
- Department of Materials, Royal School of Mines, Imperial College London, London, UK
| | - B Svendsen
- Max-Planck-Institut für Eisenforschung, 40237 Düsseldorf, Germany
- Material Mechanics, RWTH Aachen University, 52062 Aachen, Germany
| | - D Raabe
- Max-Planck-Institut für Eisenforschung, 40237 Düsseldorf, Germany.
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5
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El-Zoka AA, Kim SH, Deville S, Newman RC, Stephenson LT, Gault B. Enabling near-atomic-scale analysis of frozen water. Sci Adv 2020; 6:6/49/eabd6324. [PMID: 33277259 PMCID: PMC7821902 DOI: 10.1126/sciadv.abd6324] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 10/21/2020] [Indexed: 05/04/2023]
Abstract
Transmission electron microscopy went through a revolution enabling routine cryo-imaging of biological and (bio)chemical systems, in liquid form. Yet, these approaches typically lack advanced analytical capabilities. Here, we used atom probe tomography to analyze frozen liquids in three dimensions with subnanometer resolution. We introduce a specimen preparation strategy using nanoporous gold. We report data on 2- to 3-μm-thick layers of ice formed from both high-purity deuterated water and a solution of 50 mM NaCl in high-purity deuterated water. The analysis of the gold-ice interface reveals a substantial increase in the solute concentrations across the interface. We explore a range of experimental parameters to show that atom probe analyses of bulk aqueous specimens come with their own challenges and discuss physical processes that produce the observed phenomena. Our study demonstrates the viability of using frozen water as a carrier for near-atomic-scale analysis of objects in solution by atom probe tomography.
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Affiliation(s)
- A A El-Zoka
- Max-Planck-Institut für Eisenforschung, Düsseldorf, Germany.
| | - S-H Kim
- Max-Planck-Institut für Eisenforschung, Düsseldorf, Germany
| | - S Deville
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, 69622 Villeurbanne, France
| | - R C Newman
- Department of Chemical Engineering & Applied Chemistry, University of Toronto, Toronto, Canada
| | - L T Stephenson
- Max-Planck-Institut für Eisenforschung, Düsseldorf, Germany
| | - B Gault
- Max-Planck-Institut für Eisenforschung, Düsseldorf, Germany.
- Department of Materials, Royal School of Mines, Imperial College London, London, UK
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6
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Dubosq R, Gault B, Hatzoglou C, Schweinar K, Vurpillot F, Rogowitz A, Rantitsch G, Schneider DA. Analysis of nanoscale fluid inclusions in geomaterials by atom probe tomography: Experiments and numerical simulations. Ultramicroscopy 2020; 218:113092. [PMID: 32799006 DOI: 10.1016/j.ultramic.2020.113092] [Citation(s) in RCA: 4] [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] [Received: 02/03/2020] [Revised: 07/02/2020] [Accepted: 08/02/2020] [Indexed: 11/29/2022]
Abstract
The spatial correlation between defects in crystalline materials and trace element segregation plays a fundamental role in determining the physical and mechanical properties of a material, which is particularly important in naturally deformed materials. Herein, we combine electron backscatter diffraction, electron channelling contrast imaging, scanning transmission electron microscopy and atom probe tomography on a naturally occurring metal sulphide in an attempt to document mechanisms of element segregation in a brittle-dominated deformation regime. Within APT reconstructions, features with a high point density comprising O-rich discs stacked over As-rich spherules are observed. The combined microscopy data allow us to interpret these as nanoscale fluid inclusions. Our observations are confirmed by simulated APT experiments of core-shell particles with a core exhibiting a very low evaporation field and the shell emulating a segregated layer at the inclusion interface. Our data has significant trans-disciplinary implications to the geosciences, the material sciences, and analytical microscopy.
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Affiliation(s)
- R Dubosq
- Department of Earth and Environmental Sciences, University of Ottawa, Ottawa, Canada.
| | - B Gault
- Max-Planck-Institut für Eisenforschung GmbH, Düsseldorf, Germany; Department of Materials, Royal School of Mines, Imperial College London, London, United Kingdom
| | - C Hatzoglou
- Normandie Université, UNIROUEN, INSA Rouen, CNRS, Groupe de Physique des Matériaux, 76000 Rouen, France
| | - K Schweinar
- Max-Planck-Institut für Eisenforschung GmbH, Düsseldorf, Germany
| | - F Vurpillot
- Normandie Université, UNIROUEN, INSA Rouen, CNRS, Groupe de Physique des Matériaux, 76000 Rouen, France
| | - A Rogowitz
- Department of Geodynamics and Sedimentology, University of Vienna, Vienna, Austria
| | - G Rantitsch
- Department of Geology and Economic Geology, University of Leoben, Leoben, Austria
| | - D A Schneider
- Department of Earth and Environmental Sciences, University of Ottawa, Ottawa, Canada
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7
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Abstract
Site-specific atom probe tomography (APT) from aluminum alloys has been limited by sample preparation issues. Indeed, Ga, which is conventionally used in focused-ion beam (FIB) preparations, has a high affinity for Al grain boundaries and causes their embrittlement. This leads to high concentrations of Ga at grain boundaries after specimen preparation, unreliable compositional analyses and low specimen yield. Here, to tackle this problem, we propose to use cryo-FIB for APT specimen preparation specifically from grain boundaries in a commercial Al-alloy. We demonstrate how this setup, easily implementable on conventional Ga-FIB instruments, is efficient to prevent Ga diffusion to grain boundaries. Specimens were prepared at room temperature and at cryogenic temperature (below approx. 90K) are compared, and we confirm that at room temperature, a compositional enrichment above 15 at.% of Ga is found at the grain boundary, whereas no enrichment could be detected for the cryo-prepared sample. We propose that this is due to the decrease of the diffusion rate of Ga at low temperature. The present results could have a high impact on the understanding of aluminum and Al-alloys.
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Affiliation(s)
- L Lilensten
- Department of Microstructure Physics and Alloy Design, Max-Planck-Institut für Eisenforschung GmbH, Düsseldorf, Germany
| | - B Gault
- Department of Microstructure Physics and Alloy Design, Max-Planck-Institut für Eisenforschung GmbH, Düsseldorf, Germany
- Department of Materials, Imperial College London, Royal School of Mine, London, United Kingdom
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8
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Li T, Kasian O, Cherevko S, Zhang S, Geiger S, Scheu C, Felfer P, Raabe D, Gault B, Mayrhofer KJJ. Atomic-scale insights into surface species of electrocatalysts in three dimensions. Nat Catal 2018. [DOI: 10.1038/s41929-018-0043-3] [Citation(s) in RCA: 125] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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9
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Kwiatkowski da Silva A, Ponge D, Peng Z, Inden G, Lu Y, Breen A, Gault B, Raabe D. Phase nucleation through confined spinodal fluctuations at crystal defects evidenced in Fe-Mn alloys. Nat Commun 2018; 9:1137. [PMID: 29555984 PMCID: PMC5859155 DOI: 10.1038/s41467-018-03591-4] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [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: 08/30/2017] [Accepted: 02/23/2018] [Indexed: 11/25/2022] Open
Abstract
Analysis and design of materials and fluids requires understanding of the fundamental relationships between structure, composition, and properties. Dislocations and grain boundaries influence microstructure evolution through the enhancement of diffusion and by facilitating heterogeneous nucleation, where atoms must overcome a potential barrier to enable the early stage of formation of a phase. Adsorption and spinodal decomposition are known precursor states to nucleation and phase transition; however, nucleation remains the less well-understood step in the complete thermodynamic sequence that shapes a microstructure. Here, we report near-atomic-scale observations of a phase transition mechanism that consists in solute adsorption to crystalline defects followed by linear and planar spinodal fluctuations in an Fe-Mn model alloy. These fluctuations provide a pathway for austenite nucleation due to the higher driving force for phase transition in the solute-rich regions. Our observations are supported by thermodynamic calculations, which predict the possibility of spinodal decomposition due to magnetic ordering. Solid-state phase transitions often involve nucleation of the new phase on defects but a detailed mechanistic understanding has not been established. Here the authors observe spinodal fluctuations at dislocations and grain boundaries in an iron alloy, which may be precursors in a multistep nucleation process.
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Affiliation(s)
- A Kwiatkowski da Silva
- Max-Planck-Institut für Eisenforschung, Max-Planck-Strasse 1, 40237, Düsseldorf, Germany.
| | - D Ponge
- Max-Planck-Institut für Eisenforschung, Max-Planck-Strasse 1, 40237, Düsseldorf, Germany
| | - Z Peng
- Max-Planck-Institut für Eisenforschung, Max-Planck-Strasse 1, 40237, Düsseldorf, Germany
| | - G Inden
- Max-Planck-Institut für Eisenforschung, Max-Planck-Strasse 1, 40237, Düsseldorf, Germany
| | - Y Lu
- Database Systems and Data Mining Group, Ludwig-Maximilians-Universität München, Oettingenstraße 67, 80538, München, Germany
| | - A Breen
- Max-Planck-Institut für Eisenforschung, Max-Planck-Strasse 1, 40237, Düsseldorf, Germany
| | - B Gault
- Max-Planck-Institut für Eisenforschung, Max-Planck-Strasse 1, 40237, Düsseldorf, Germany
| | - D Raabe
- Max-Planck-Institut für Eisenforschung, Max-Planck-Strasse 1, 40237, Düsseldorf, Germany
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10
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Yeoh WK, Cui XY, Gault B, De Silva KSB, Xu X, Liu HW, Yen HW, Wong D, Bao P, Larson DJ, Martin I, Li WX, Zheng RK, Wang XL, Dou SX, Ringer SP. On the roles of graphene oxide doping for enhanced supercurrent in MgB2 based superconductors. Nanoscale 2014; 6:6166-6172. [PMID: 24793305 DOI: 10.1039/c4nr00415a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Due to their graphene-like properties after oxygen reduction, incorporation of graphene oxide (GO) sheets into correlated-electron materials offers a new pathway for tailoring their properties. Fabricating GO nanocomposites with polycrystalline MgB2 superconductors leads to an order of magnitude enhancement of the supercurrent at 5 K/8 T and 20 K/4 T. Herein, we introduce a novel experimental approach to overcome the formidable challenge of performing quantitative microscopy and microanalysis of such composites, so as to unveil how GO doping influences the structure and hence the material properties. Atom probe microscopy and electron microscopy were used to directly image the GO within the MgB2, and we combined these data with computational simulations to derive the property-enhancing mechanisms. Our results reveal synergetic effects of GO, namely, via localized atomic (carbon and oxygen) doping as well as texturing of the crystals, which provide both inter- and intra-granular flux pinning. This study opens up new insights into how low-dimensional nanostructures can be integrated into composites to modify the overall properties, using a methodology amenable to a wide range of applications.
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Affiliation(s)
- W K Yeoh
- School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, New South Wales 2006, Australia.
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12
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13
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Yeoh WK, Gault B, Cui XY, Zhu C, Moody MP, Li L, Zheng RK, Li WX, Wang XL, Dou SX, Sun GL, Lin CT, Ringer SP. Direct observation of local potassium variation and its correlation to electronic inhomogeneity in (Ba(1-x)K(x))Fe2As2 pnictide. Phys Rev Lett 2011; 106:247002. [PMID: 21770591 DOI: 10.1103/physrevlett.106.247002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Indexed: 05/31/2023]
Abstract
Local fluctuations in the distribution of dopant atoms are thought to cause the nanoscale electronic disorder or phase separation in pnictide superconductors. Atom probe tomography has enabled the first direct observations of dopant species clustering in a K-doped 122-phase pnictide. First-principles calculations suggest the coexistence of static magnetism and superconductivity on a lattice parameter length scale over a wide range of dopant concentrations. Our results provide evidence for a mixed scenario of phase coexistence and phase separation, depending on local dopant atom distributions.
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Affiliation(s)
- W K Yeoh
- Australian Centre for Microscopy & Microanalysis, University of Sydney, Sydney, New South Wales, Australia.
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14
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Hudson D, Smith G, Gault B. Optimisation of mass ranging for atom probe microanalysis and application to the corrosion processes in Zr alloys. Ultramicroscopy 2011; 111:480-6. [DOI: 10.1016/j.ultramic.2010.11.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2010] [Revised: 10/26/2010] [Accepted: 11/14/2010] [Indexed: 10/18/2022]
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15
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Müller M, Saxey D, Smith G, Gault B. Some aspects of the field evaporation behaviour of GaSb. Ultramicroscopy 2011; 111:487-92. [DOI: 10.1016/j.ultramic.2010.11.019] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2010] [Revised: 11/01/2010] [Accepted: 11/14/2010] [Indexed: 10/18/2022]
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16
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Gault B, Haley D, de Geuser F, Moody M, Marquis E, Larson D, Geiser B. Advances in the reconstruction of atom probe tomography data. Ultramicroscopy 2011; 111:448-57. [DOI: 10.1016/j.ultramic.2010.11.016] [Citation(s) in RCA: 171] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2010] [Revised: 10/15/2010] [Accepted: 11/14/2010] [Indexed: 10/18/2022]
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17
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Stephenson LT, Moody MP, Gault B, Ringer SP. Estimating the physical cluster-size distribution within materials using atom-probe. Microsc Res Tech 2010; 74:799-803. [PMID: 23939666 DOI: 10.1002/jemt.20958] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2010] [Accepted: 09/22/2010] [Indexed: 11/11/2022]
Affiliation(s)
- L T Stephenson
- Australian Center for Microscopy and Microanalysis, The University of Sydney, New South Wales 2006, Australia.
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18
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Gault B, Moody MP, Saxey DW, Cairney JM, Liu Z, Zheng R, Marceau RKW, Liddicoat PV, Stephenson LT, Ringer SP. Atom Probe Tomography at The University of Sydney. ACTA ACUST UNITED AC 2008. [DOI: 10.1007/978-3-540-77968-1_15] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
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19
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Gault B, Vella A, Vurpillot F, Menand A, Blavette D, Deconihout B. Optical and thermal processes involved in ultrafast laser pulse interaction with a field emitter. Ultramicroscopy 2007; 107:713-9. [PMID: 17482367 DOI: 10.1016/j.ultramic.2007.02.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
In the interaction between ultrafast laser pulses and a field emitter both optical and thermal processes are involved. In this paper, these physical process, and their timescales, are experimentally explored. Simple models are proposed to explain the observed experimental behaviour, and the influence of various parameters are investigated. In the case of optical processes, it is shown that the optical field is greatly enhanced at the tip apex, and that field evaporation could be induced by an optical non-linear effect called optical rectification. In the case of thermal processes, it is shown that the temperature rise because of light absorption can be determined and that the cooling process of the tip surface can be studied by pump probe measurements.
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Affiliation(s)
- B Gault
- Groupe de Physique des Matériaux, UMR CNRS 6634, Institut des Matériaux de Rouen, 76801 Saint-Etienne-du-Rouvray Cedex, France.
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Gault B, Mottay E, Courjaud A, Vurpillot F, Bostel A, Menand A, Deconihout B. Ultrafast Laser Assisted Field Evaporation and Atom Probe Tomography Applications. ACTA ACUST UNITED AC 2007. [DOI: 10.1088/1742-6596/59/1/028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Deconihout B, Vurpillot F, Gault B, Da Costa G, Bouet M, Bostel A, Blavette D, Hideur A, Martel G, Brunel M. Toward a laser assisted wide-angle tomographic atom-probe. SURF INTERFACE ANAL 2007. [DOI: 10.1002/sia.2491] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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McLennan A, Banks D, Gass J, Gault B, McKie A. Similarities not differences: an exploration of the impact of change upon a group of nursing lecturers within a university setting. Nurse Educ Today 2001; 21:391-397. [PMID: 11403586 DOI: 10.1054/nedt.2001.0572] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The concepts of collaboration and partnership currently have extensive impact upon health care providers and higher education institutions. One of the challenges is to develop networks which will foster partnerships able to react, and contribute, to an ever-evolving educational culture. These themes are illustrated by using the example of one school of nursing and midwifery, and the collective experience of a number of its academic staff. By focusing on distinct features of collaboration (strategic planning, origins of change, group dynamics and building a community), the authors seek to explore the impact of an educational culture in an attempt to provide meaning to their recent experiences. In so doing, group identity is explored and the prospect for creating partnerships across disciplines ('similarities rather than differences') is considered.
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Affiliation(s)
- A McLennan
- The Robert Gordon University, School of Nursing and Midwifery, Northern College of Education, Hilton Campus, Hilton Place, Aberdeen, AB24 4FP, UK
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Abstract
This article, based on data from the Commonwealth Fund 1998 Survey of Women's Health, examines the relationship between socioeconomic status (SES) and women's health. Women living in poverty are less likely than their higher-income counterparts to have health insurance and use preventive services, and more likely to have access problems, suffer from chronic illnesses, and report low overall health scores. Women with low educational attainment are also less likely to have health insurance and to use preventive services, and more likely to report poorer health status than women with a college education. We conclude with implications for public policy.
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Affiliation(s)
- H Mead
- George Washington University and Institute for Women's Policy Research, Washington, DC, USA
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