1
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Abstract
Rechargeable Zn metal batteries (RZMBs) may provide a more sustainable and lower-cost alternative to established battery technologies in meeting energy storage applications of the future. However, the most promising electrolytes for RZMBs are generally aqueous and require high concentrations of salt(s) to bring efficiencies toward commercially viable levels and mitigate water-originated parasitic reactions including hydrogen evolution and corrosion. Electrolytes based on nonaqueous solvents are promising for avoiding these issues, but full cell performance demonstrations with solvents other than water have been very limited. To address these challenges, we investigated MeOH as an alternative electrolyte solvent. These MeOH-based electrolytes exhibited exceptional Zn reversibility over a wide temperature range, with a Coulombic efficiency > 99.5% at 50% Zn utilization without cell short-circuit behavior for > 1,800 h. More important, this remarkable performance translates well to Zn || metal-free organic cathode full cells, supporting < 6% capacity decay after > 800 cycles at -40 °C.
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2
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Petkov V, Ren Y. Critical cation-anion radius ratio and two-dimensional antiferromagnetism in van der Waals TMPS 3(TM = Mn, Fe, Ni). JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:175404. [PMID: 35130524 DOI: 10.1088/1361-648x/ac527a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 02/07/2022] [Indexed: 06/14/2023]
Abstract
Two-dimensional TMPS3antiferromagnets, transition metal (TM) = Mn, Fe, Ni, are studied by high-energy x-ray diffraction and atomic pair distribution analysis over a broad temperature range. Results show that the compounds exhibit common average but distinct local atomic structure, including distinct distortions of the constituent TM-S octahedra, magnitude and direction of atomic displacements, TM-TM distances and TM-S-TM bond angles. The differences in the local structure may be rationalized in terms of the Pauling's rule for the critical ratio of TM2+cation and S2-anion radii for octahedral coordination. We argue that the observed differences in the local structure are behind the differences in the antiferromagnetic properties of TMPS3compounds, including different magnetic anisotropy and Neel temperature.
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Affiliation(s)
- Valeri Petkov
- Department of Physics, Central Michigan University, Mt. Pleasant, Michigan 48858, United States of America
| | - Yang Ren
- X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, United States of America
- Department of Physics, City University of Hong Kong, Kowloon, Hong Kong, People's Republic of China
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3
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Terban MW, Billinge SJL. Structural Analysis of Molecular Materials Using the Pair Distribution Function. Chem Rev 2022; 122:1208-1272. [PMID: 34788012 PMCID: PMC8759070 DOI: 10.1021/acs.chemrev.1c00237] [Citation(s) in RCA: 44] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Indexed: 12/16/2022]
Abstract
This is a review of atomic pair distribution function (PDF) analysis as applied to the study of molecular materials. The PDF method is a powerful approach to study short- and intermediate-range order in materials on the nanoscale. It may be obtained from total scattering measurements using X-rays, neutrons, or electrons, and it provides structural details when defects, disorder, or structural ambiguities obscure their elucidation directly in reciprocal space. While its uses in the study of inorganic crystals, glasses, and nanomaterials have been recently highlighted, significant progress has also been made in its application to molecular materials such as carbons, pharmaceuticals, polymers, liquids, coordination compounds, composites, and more. Here, an overview of applications toward a wide variety of molecular compounds (organic and inorganic) and systems with molecular components is presented. We then present pedagogical descriptions and tips for further implementation. Successful utilization of the method requires an interdisciplinary consolidation of material preparation, high quality scattering experimentation, data processing, model formulation, and attentive scrutiny of the results. It is hoped that this article will provide a useful reference to practitioners for PDF applications in a wide realm of molecular sciences, and help new practitioners to get started with this technique.
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Affiliation(s)
- Maxwell W. Terban
- Max
Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | - Simon J. L. Billinge
- Department
of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, United States
- Condensed
Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, United States
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4
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Griep MH, Sellers MS, Subhash B, Fakner AM, West AL, Bedford NM. Towards the identification of the gold binding region within trypsin stabilized nanoclusters using microwave synthesis routes. NANOSCALE 2021; 13:1061-1068. [PMID: 33393579 DOI: 10.1039/d0nr07068h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Elucidating the location of stabilized nanoclusters within their protein hosts is an existing challenge towards the optimized development of functional protein-nanoclusters. While nanoclusters of various metal compositions can be readily synthesized within a wide array of protein hosts and exhibit tailorable properties, the inability to identify the cluster stabilization region prevents controllable property manipulation of both metallic and protein components. Additionally, the ability to synthesize protein-nanoclusters in a consistent and high-throughput fashion is also highly desirable. In this effort, trypsin stabilized gold nanoclusters are synthesized through standard and microwave-enabled methodologies to determine the impact of processing parameters on the materials physical and functional properties. Density functional theory simulations are employed to localize high probability regions within the trypsin enzyme for Au25 cluster stabilization, which reveal that cluster location is likely within close proximity of the trypsin active region. Trypsin activity measurements support our findings from DFT, as trypsin enzymatic activity is eliminated following cluster growth and stabilization. Moreover, studies on the reactivity of Au NCs and synchrotron characterization measurements further reveal that clusters made by microwave-based techniques exhibit slight structural differences to those made via standard methodologies, indicating that microwave-based syntheses largely maintain the native structural attributes despite the faster synthetic conditions. Overall, this work illustrates the importance of understanding the connections between synthetic conditions, atomic-scale structure, and materials properties that can be potentially used to further tune the properties of metal cluster-protein materials for future applications.
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Affiliation(s)
- Mark H Griep
- Weapons and Materials Research Directorate, CCDC Army Research Laboratory, Aberdeen Proving Ground, MD 21005, USA
| | - Michael S Sellers
- Weapons and Materials Research Directorate, CCDC Army Research Laboratory, Aberdeen Proving Ground, MD 21005, USA
| | - Bijil Subhash
- School of Chemical Engineering, University of New South Wales, Sydney, NSW 2052, Australia.
| | - Alexis M Fakner
- Weapons and Materials Research Directorate, CCDC Army Research Laboratory, Aberdeen Proving Ground, MD 21005, USA
| | - Abby L West
- Weapons and Materials Research Directorate, CCDC Army Research Laboratory, Aberdeen Proving Ground, MD 21005, USA
| | - Nicholas M Bedford
- School of Chemical Engineering, University of New South Wales, Sydney, NSW 2052, Australia.
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5
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Kamaeva LV, Ryltsev RE, Suslov AA, Chtchelkatchev NM. Effect of copper concentration on the structure and properties of Al-Cu-Fe and Al-Cu-Ni melts. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:224003. [PMID: 32032016 DOI: 10.1088/1361-648x/ab73a6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We address a relationship between properties of liquid and solid states by comparing structural characteristics and viscosity in Al-Cu-Fe and Al-Cu-Ni melts. The former system forms an equilibrium quasicrystalline phase but the latter does not. We show that the concentration behavior of the viscosity, melting temperature and characteristics of the chemical short-range order correlate with each other. The main structural differences between the melts are related to the peculiarities of their electronic structure, which is the same for liquid and solid states near the melting temperature.
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Affiliation(s)
- L V Kamaeva
- Udmurt Federal Research Center, Ural Branch of Russian Academy of Sciences, 426068 Izhevsk, Russia. Vereshchagin Institute for High Pressure Physics, Russian Academy of Sciences, 108840 Troitsk, Moscow, Russia
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6
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Hunter KI, Bedford N, Schramke K, Kortshagen UR. Probing Dopant Locations in Silicon Nanocrystals via High Energy X-ray Diffraction and Reverse Monte Carlo Simulation. NANO LETTERS 2020; 20:852-859. [PMID: 31869231 DOI: 10.1021/acs.nanolett.9b03025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Understanding the locations of dopant atoms in ensembles of nanocrystals is crucial to controlling the dopants' function. While electron microscopy and atom probe tomography methods allow investigation of dopant location for small numbers of nanocrystals, assessing large ensembles has remained a challenge. Here, we are using high energy X-ray diffraction (HE-XRD) and structure reconstruction via reverse Monte Carlo simulation to characterize nanocrystal structure and dopant locations in ensembles of highly boron and phosphorus doped silicon nanocrystals (Si NCs). These plasma-synthesized NCs are a particularly intriguing test system for such an investigation, as elemental analysis suggests that Si NCs can be "hyperdoped" beyond the thermodynamic solubility limit in bulk silicon. Yet, free carrier densities derived from local surface plasmon resonances suggest that only a fraction of dopants are active. We demonstrate that the structural characteristics garnered from HE-XRD and structure reconstruction elucidate dopant location and doping efficacy for doped Si NCs from an atomic-scale perspective.
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Affiliation(s)
- Katharine I Hunter
- Department of Mechanical Engineering , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Nicholas Bedford
- School of Chemical Engineering , University of New South Wales , Sydney , New South Wales 2052 , Australia
| | - Katelyn Schramke
- Department of Mechanical Engineering , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Uwe R Kortshagen
- Department of Mechanical Engineering , University of Minnesota , Minneapolis , Minnesota 55455 , United States
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7
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Baddour FG, Roberts EJ, To AT, Wang L, Habas SE, Ruddy DA, Bedford NM, Wright J, Nash CP, Schaidle JA, Brutchey RL, Malmstadt N. An Exceptionally Mild and Scalable Solution-Phase Synthesis of Molybdenum Carbide Nanoparticles for Thermocatalytic CO2 Hydrogenation. J Am Chem Soc 2020; 142:1010-1019. [DOI: 10.1021/jacs.9b11238] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Frederick G. Baddour
- National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, Colorado 80401-3305, United States
| | - Emily J. Roberts
- Department of Chemistry, University of Southern California, 840 Downey Way, Los Angeles, California 90089-0744, United States
| | - Anh T. To
- National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, Colorado 80401-3305, United States
| | - Lu Wang
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, 925 Bloom Walk, Los Angeles, California 90089-1211, United States
| | - Susan E. Habas
- National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, Colorado 80401-3305, United States
| | - Daniel A. Ruddy
- National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, Colorado 80401-3305, United States
| | - Nicholas M. Bedford
- School of Chemical Engineering, University of New South Wales, High Street, Sydney, New South Wales 2052, Australia
| | - Joshua Wright
- Department of Physics, Illinois Institute of Technology, 3101 South Dearborn Street, Chicago, Illinois 60616, United States
| | - Connor P. Nash
- National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, Colorado 80401-3305, United States
| | - Joshua A. Schaidle
- National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, Colorado 80401-3305, United States
| | - Richard L. Brutchey
- Department of Chemistry, University of Southern California, 840 Downey Way, Los Angeles, California 90089-0744, United States
| | - Noah Malmstadt
- Department of Chemistry, University of Southern California, 840 Downey Way, Los Angeles, California 90089-0744, United States
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, 925 Bloom Walk, Los Angeles, California 90089-1211, United States
- Department of Biomedical Engineering, University of Southern California, 1042 Downey Way, Los Angeles, California 90089-0260, United States
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8
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Daiyan R, Lovell EC, Bedford NM, Saputera WH, Wu K, Lim S, Horlyck J, Ng YH, Lu X, Amal R. Modulating Activity through Defect Engineering of Tin Oxides for Electrochemical CO 2 Reduction. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2019; 6:1900678. [PMID: 31559127 PMCID: PMC6755522 DOI: 10.1002/advs.201900678] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Revised: 05/08/2019] [Indexed: 05/13/2023]
Abstract
The large-scale application of electrochemical reduction of CO2, as a viable strategy to mitigate the effects of anthropogenic climate change, is hindered by the lack of active and cost-effective electrocatalysts that can be generated in bulk. To this end, SnO2 nanoparticles that are prepared using the industrially adopted flame spray pyrolysis (FSP) technique as active catalysts are reported for the conversion of CO2 to formate (HCOO-), exhibiting a FEHCOO - of 85% with a current density of -23.7 mA cm-2 at an applied potential of -1.1 V versus reversible hydrogen electrode. Through tuning of the flame synthesis conditions, the amount of oxygen hole center (OHC; Sn≡O●) is synthetically manipulated, which plays a vital role in CO2 activation and thereby governing the high activity displayed by the FSP-SnO2 catalysts for formate production. The controlled generation of defects through a simple, scalable fabrication technique presents an ideal approach for rationally designing active CO2 reduction reactions catalysts.
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Affiliation(s)
- Rahman Daiyan
- Particles and Catalysis Research LaboratorySchool of Chemical EngineeringThe University of New South WalesSydneyNSW2052Australia
| | - Emma Catherine Lovell
- Particles and Catalysis Research LaboratorySchool of Chemical EngineeringThe University of New South WalesSydneyNSW2052Australia
| | - Nicholas M. Bedford
- Particles and Catalysis Research LaboratorySchool of Chemical EngineeringThe University of New South WalesSydneyNSW2052Australia
| | - Wibawa Hendra Saputera
- Particles and Catalysis Research LaboratorySchool of Chemical EngineeringThe University of New South WalesSydneyNSW2052Australia
- Department of Chemical EngineeringInstitut Teknologi BandungBandung40132Indonesia
| | - Kuang‐Hsu Wu
- Particles and Catalysis Research LaboratorySchool of Chemical EngineeringThe University of New South WalesSydneyNSW2052Australia
| | - Sean Lim
- Electron Microscope UnitThe University of New South WalesSydneyNSW2052Australia
| | - Jonathan Horlyck
- Particles and Catalysis Research LaboratorySchool of Chemical EngineeringThe University of New South WalesSydneyNSW2052Australia
| | - Yun Hau Ng
- School of Energy and EnvironmentCity University of Hong KongHong KongChina
| | - Xunyu Lu
- Particles and Catalysis Research LaboratorySchool of Chemical EngineeringThe University of New South WalesSydneyNSW2052Australia
| | - Rose Amal
- Particles and Catalysis Research LaboratorySchool of Chemical EngineeringThe University of New South WalesSydneyNSW2052Australia
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9
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Juhás P, Louwen JN, van Eijck L, Vogt E, Billinge S. PDFgetN3: atomic pair distribution functions from neutron powder diffraction data using ad hoc corrections. J Appl Crystallogr 2018. [DOI: 10.1107/s1600576718010002] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
PDFgetN3, a new software tool for the extraction of pair distribution functions (PDFs) from neutron powder diffraction intensity data, is described. Its use is demonstrated with constant-wavelength neutron data measured at the new powder diffractometer PEARL at the Delft University of Technology. PDFgetN3 uses an ad hoc data collection protocol similar to PDFgetX3. The quality of the resulting PDFs is assessed by structure refinement and by comparison with established results from synchrotron X-ray scattering.
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10
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Garcia-Bennett AE, Lau M, Bedford N. Probing the Amorphous State of Pharmaceutical Compounds Within Mesoporous Material Using Pair Distribution Function Analysis. J Pharm Sci 2018; 107:2216-2224. [DOI: 10.1016/j.xphs.2018.03.029] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 02/28/2018] [Accepted: 03/16/2018] [Indexed: 11/16/2022]
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11
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Merrill NA, Nitka TT, McKee EM, Merino KC, Drummy LF, Lee S, Reinhart B, Ren Y, Munro CJ, Pylypenko S, Frenkel AI, Bedford NM, Knecht MR. Effects of Metal Composition and Ratio on Peptide-Templated Multimetallic PdPt Nanomaterials. ACS APPLIED MATERIALS & INTERFACES 2017; 9:8030-8040. [PMID: 28156088 DOI: 10.1021/acsami.6b11651] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
It can be difficult to simultaneously control the size, composition, and morphology of metal nanomaterials under benign aqueous conditions. For this, bioinspired approaches have become increasingly popular due to their ability to stabilize a wide array of metal catalysts under ambient conditions. In this regard, we used the R5 peptide as a three-dimensional template for formation of PdPt bimetallic nanomaterials. Monometallic Pd and Pt nanomaterials have been shown to be highly reactive toward a variety of catalytic processes, but by forming bimetallic species, increased catalytic activity may be realized. The optimal metal-to-metal ratio was determined by varying the Pd:Pt ratio to obtain the largest increase in catalytic activity. To better understand the morphology and the local atomic structure of the materials, the bimetallic PdPt nanomaterials were extensively studied by transmission electron microscopy, extended X-ray absorption fine structure spectroscopy, X-ray photoelectron spectroscopy, and pair distribution function analysis. The resulting PdPt materials were determined to form multicomponent nanostructures where the Pt component demonstrated varying degrees of oxidation based upon the Pd:Pt ratio. To test the catalytic reactivity of the materials, olefin hydrogenation was conducted, which indicated a slight catalytic enhancement for the multicomponent materials. These results suggest a strong correlation between the metal ratio and the stabilizing biotemplate in controlling the final materials morphology, composition, and the interactions between the two metal species.
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Affiliation(s)
- Nicholas A Merrill
- Department of Chemistry, University of Miami , 1301 Memorial Drive, Coral Gables, Florida 33146, United States
| | - Tadeusz T Nitka
- Department of Chemistry, Colorado School of Mines , Golden, Colorado 80401, United States
| | - Erik M McKee
- Department of Chemistry, University of Miami , 1301 Memorial Drive, Coral Gables, Florida 33146, United States
| | - Kyle C Merino
- Department of Chemistry, University of Miami , 1301 Memorial Drive, Coral Gables, Florida 33146, United States
| | - Lawrence F Drummy
- Materials and Manufacturing Directorate, Air Force Research Laboratory , Wright-Patterson Air Force Base, Ohio 45433, United States
| | - Sungsik Lee
- X-ray Science Division, Argonne National Laboratory , 9700 South Cass Avenue, Argonne, Illinois 60439, United States
| | - Benjamin Reinhart
- X-ray Science Division, Argonne National Laboratory , 9700 South Cass Avenue, Argonne, Illinois 60439, United States
| | - Yang Ren
- X-ray Science Division, Argonne National Laboratory , 9700 South Cass Avenue, Argonne, Illinois 60439, United States
| | - Catherine J Munro
- Department of Chemistry, University of Miami , 1301 Memorial Drive, Coral Gables, Florida 33146, United States
| | - Svitlana Pylypenko
- Department of Chemistry, Colorado School of Mines , Golden, Colorado 80401, United States
| | - Anatoly I Frenkel
- Department of Materials Science and Chemical Engineering, Stony Brook University , Stony Brook, New York 11794, United States
| | - Nicholas M Bedford
- Department of Chemistry, University of Miami , 1301 Memorial Drive, Coral Gables, Florida 33146, United States
- Materials and Manufacturing Directorate, Air Force Research Laboratory , Wright-Patterson Air Force Base, Ohio 45433, United States
- Applied Chemicals and Materials Division, National Institute of Standards and Technology , Boulder, Colorado 80305, United States
| | - Marc R Knecht
- Department of Chemistry, University of Miami , 1301 Memorial Drive, Coral Gables, Florida 33146, United States
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12
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Candelaria SL, Bedford NM, Woehl TJ, Rentz NS, Showalter AR, Pylypenko S, Bunker BA, Lee S, Reinhart B, Ren Y, Ertem SP, Coughlin EB, Sather NA, Horan JL, Herring AM, Greenlee LF. Multi-Component Fe–Ni Hydroxide Nanocatalyst for Oxygen Evolution and Methanol Oxidation Reactions under Alkaline Conditions. ACS Catal 2016. [DOI: 10.1021/acscatal.6b02552] [Citation(s) in RCA: 125] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Stephanie L. Candelaria
- Applied
Chemicals and Materials Division, National Institute of Standards and Technology, Boulder, Colorado 80305, United States
| | - Nicholas M. Bedford
- Applied
Chemicals and Materials Division, National Institute of Standards and Technology, Boulder, Colorado 80305, United States
| | - Taylor J. Woehl
- Applied
Chemicals and Materials Division, National Institute of Standards and Technology, Boulder, Colorado 80305, United States
| | - Nikki S. Rentz
- Applied
Chemicals and Materials Division, National Institute of Standards and Technology, Boulder, Colorado 80305, United States
| | - Allison R. Showalter
- Department
of Physics, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Svitlana Pylypenko
- Department
of Chemistry, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Bruce A. Bunker
- Department
of Physics, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Sungsik Lee
- X-Ray
Sciences Division, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Benjamin Reinhart
- X-Ray
Sciences Division, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Yang Ren
- X-Ray
Sciences Division, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - S. Piril Ertem
- Department
of Polymer Science and Engineering, University of Massachusetts, Amherst, Massachusetts 01003, United States
| | - E. Bryan Coughlin
- Department
of Polymer Science and Engineering, University of Massachusetts, Amherst, Massachusetts 01003, United States
| | - Nicholas A. Sather
- Department
of Chemical and Biological Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
- Department
of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - James L. Horan
- Department
of Chemical and Biological Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Andrew M. Herring
- Department
of Chemical and Biological Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Lauren F. Greenlee
- Applied
Chemicals and Materials Division, National Institute of Standards and Technology, Boulder, Colorado 80305, United States
- Ralph
E. Martin Department of Chemical Engineering, University of Arkansas, Fayetteville, Arkansas 72701, United States
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13
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Bedford NM, Showalter AR, Woehl TJ, Hughes ZE, Lee S, Reinhart B, Ertem SP, Coughlin EB, Ren Y, Walsh TR, Bunker BA. Peptide-Directed PdAu Nanoscale Surface Segregation: Toward Controlled Bimetallic Architecture for Catalytic Materials. ACS NANO 2016; 10:8645-59. [PMID: 27583654 DOI: 10.1021/acsnano.6b03963] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Bimetallic nanoparticles are of immense scientific and technological interest given the synergistic properties observed when two different metallic species are mixed at the nanoscale. This is particularly prevalent in catalysis, where bimetallic nanoparticles often exhibit improved catalytic activity and durability over their monometallic counterparts. Yet despite intense research efforts, little is understood regarding how to optimize bimetallic surface composition and structure synthetically using rational design principles. Recently, it has been demonstrated that peptide-enabled routes for nanoparticle synthesis result in materials with sequence-dependent catalytic properties, providing an opportunity for rational design through sequence manipulation. In this study, bimetallic PdAu nanoparticles are synthesized with a small set of peptides containing known Pd and Au binding motifs. The resulting nanoparticles were extensively characterized using high-resolution scanning transmission electron microscopy, X-ray absorption spectroscopy, and high-energy X-ray diffraction coupled to atomic pair distribution function analysis. Structural information obtained from synchrotron radiation methods was then used to generate model nanoparticle configurations using reverse Monte Carlo simulations, which illustrate sequence dependence in both surface structure and surface composition. Replica exchange with solute tempering molecular dynamics simulations were also used to predict the modes of peptide binding on monometallic surfaces, indicating that different sequences bind to the metal interfaces via different mechanisms. As a testbed reaction, electrocatalytic methanol oxidation experiments were performed, wherein differences in catalytic activity are clearly observed in materials with identical bimetallic composition. Taken together, this study indicates that peptides could be used to arrive at bimetallic surfaces with enhanced catalytic properties, which could be leveraged for rational bimetallic nanoparticle design using peptide-enabled approaches.
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Affiliation(s)
- Nicholas M Bedford
- Applied Chemical and Materials Division, National Institute of Standards and Technology , Boulder, Colorado 80305, United States
| | - Allison R Showalter
- Department of Physics, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Taylor J Woehl
- Applied Chemical and Materials Division, National Institute of Standards and Technology , Boulder, Colorado 80305, United States
| | - Zak E Hughes
- Institute for Frontier Materials, Deakin University , Geelong, Victoria 3216, Australia
| | - Sungsik Lee
- X-ray Sciences Division, Argonne National Laboratory , Argonne, Illinois 60439, United States
| | - Benjamin Reinhart
- X-ray Sciences Division, Argonne National Laboratory , Argonne, Illinois 60439, United States
| | - S Piril Ertem
- Department of Polymer Science and Engineering, University of Massachusetts , Amherst, Massachusetts 01003, United States
| | - E Bryan Coughlin
- Department of Polymer Science and Engineering, University of Massachusetts , Amherst, Massachusetts 01003, United States
| | - Yang Ren
- X-ray Sciences Division, Argonne National Laboratory , Argonne, Illinois 60439, United States
| | - Tiffany R Walsh
- Institute for Frontier Materials, Deakin University , Geelong, Victoria 3216, Australia
| | - Bruce A Bunker
- Department of Physics, University of Notre Dame , Notre Dame, Indiana 46556, United States
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14
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Peptide Binding for Bio-Based Nanomaterials. Methods Enzymol 2016. [PMID: 27586350 DOI: 10.1016/bs.mie.2016.05.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Peptide-based strategies represent transformative approaches to fabricate functional inorganic materials under sustainable conditions by modeling the methods exploited in biology. In general, peptides with inorganic affinity and specificity have been isolated from organisms and through biocombinatorial selection techniques (ie, phage and cell surface display). These peptides recognize and bind the inorganic surface through a series of noncovalent interactions, driven by both enthalpic and entropic contributions, wherein the biomolecules wrap the metallic nanoparticle structure. Through these interactions, modification of the inorganic surface can be accessed to drive the incorporation of significantly disordered surface metal atoms, which have been found to be highly catalytically active for a variety of chemical transformations. We have employed synthetic, site-directed mutagenesis studies to reveal localized binding effects of the peptide at the metallic nanoparticle structure to begin to identify the biological basis of control over biomimetic nanoparticle catalytic activity. The protocols described herein were used to fabricate and characterize peptide-capped nanoparticles in atomic resolution to identify peptide sequence effects on the surface structure of the materials, which can then be directly correlated to the catalytic activity to identify structure/function relationships.
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15
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Merrill NA, McKee EM, Merino KC, Drummy LF, Lee S, Reinhart B, Ren Y, Frenkel AI, Naik RR, Bedford NM, Knecht MR. Identifying the Atomic-Level Effects of Metal Composition on the Structure and Catalytic Activity of Peptide-Templated Materials. ACS NANO 2015; 9:11968-11979. [PMID: 26497843 DOI: 10.1021/acsnano.5b04665] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Bioinspired approaches for the formation of metallic nanomaterials have been extensively employed for a diverse range of applications including diagnostics and catalysis. These materials can often be used under sustainable conditions; however, it is challenging to control the material size, morphology, and composition simultaneously. Here we have employed the R5 peptide, which forms a 3D scaffold to direct the size and linear shape of bimetallic PdAu nanomaterials for catalysis. The materials were prepared at varying Pd:Au ratios to probe optimal compositions to achieve maximal catalytic efficiency. These materials were extensively characterized at the atomic level using transmission electron microscopy, extended X-ray absorption fine structure spectroscopy, and atomic pair distribution function analysis derived from high-energy X-ray diffraction patterns to provide highly resolved structural information. The results confirmed PdAu alloy formation, but also demonstrated that significant surface structural disorder was present. The catalytic activity of the materials was studied for olefin hydrogenation, which demonstrated enhanced reactivity from the bimetallic structures. These results present a pathway to the bioinspired production of multimetallic materials with enhanced properties, which can be assessed via a suite of characterization methods to fully ascertain structure/function relationships.
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Affiliation(s)
- Nicholas A Merrill
- Department of Chemistry, University of Miami , 1301 Memorial Drive, Coral Gables, Florida 33146, United States
| | - Erik M McKee
- Department of Chemistry, University of Miami , 1301 Memorial Drive, Coral Gables, Florida 33146, United States
| | - Kyle C Merino
- Department of Chemistry, University of Miami , 1301 Memorial Drive, Coral Gables, Florida 33146, United States
| | - Lawrence F Drummy
- Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson Air Force Base , Dayton, Ohio 45433, United States
| | - Sungsik Lee
- X-Ray Science Division, Argonne National Laboratory , 9700 S. Cass Avenue, Argonne, Illinois 60439, United States
| | - Benjamin Reinhart
- X-Ray Science Division, Argonne National Laboratory , 9700 S. Cass Avenue, Argonne, Illinois 60439, United States
| | - Yang Ren
- X-Ray Science Division, Argonne National Laboratory , 9700 S. Cass Avenue, Argonne, Illinois 60439, United States
| | - Anatoly I Frenkel
- Department of Physics, Yeshiva University , New York, New York 10016, United States
| | - Rajesh R Naik
- Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson Air Force Base , Dayton, Ohio 45433, United States
| | - Nicholas M Bedford
- Department of Chemistry, University of Miami , 1301 Memorial Drive, Coral Gables, Florida 33146, United States
- Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson Air Force Base , Dayton, Ohio 45433, United States
- Applied Chemicals and Materials Division, National Institute of Standards and Technology , Boulder, Colorado 80305, United States
| | - Marc R Knecht
- Department of Chemistry, University of Miami , 1301 Memorial Drive, Coral Gables, Florida 33146, United States
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16
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Bedford NM, Hughes ZE, Tang Z, Li Y, Briggs BD, Ren Y, Swihart MT, Petkov VG, Naik RR, Knecht MR, Walsh TR. Sequence-Dependent Structure/Function Relationships of Catalytic Peptide-Enabled Gold Nanoparticles Generated under Ambient Synthetic Conditions. J Am Chem Soc 2015; 138:540-8. [DOI: 10.1021/jacs.5b09529] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Nicholas M. Bedford
- Applied
Chemical and Materials Division, National Institute of Standards and Technology, Boulder, Colorado 80305, United States
- Materials
and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson
AFB, Ohio 45433, United States
- Department
of Chemistry, University of Miami, Coral Gables, Florida 33146, United States
| | - Zak E. Hughes
- Institute
for Frontier Materials, Deakin University, Geelong, Victoria 3216, Australia
| | - Zhenghua Tang
- Department
of Chemistry, University of Miami, Coral Gables, Florida 33146, United States
- New
Energy Research Institute, School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou 510006, China
| | - Yue Li
- Chemical
and Biological Engineering, State University of New York at Buffalo, Buffalo, New York 14260, United States
| | - Beverly D. Briggs
- Department
of Chemistry, University of Miami, Coral Gables, Florida 33146, United States
| | - Yang Ren
- Advanced
Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Mark T. Swihart
- Chemical
and Biological Engineering, State University of New York at Buffalo, Buffalo, New York 14260, United States
| | - Valeri G. Petkov
- Department
of Physics, Central Michigan University, Mt. Pleasant, Michigan 48858, United States
| | - Rajesh R. Naik
- Materials
and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson
AFB, Ohio 45433, United States
| | - Marc R. Knecht
- Department
of Chemistry, University of Miami, Coral Gables, Florida 33146, United States
| | - Tiffany R. Walsh
- Institute
for Frontier Materials, Deakin University, Geelong, Victoria 3216, Australia
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17
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Prasai B, Wilson AR, Wiley BJ, Ren Y, Petkov V. On the road to metallic nanoparticles by rational design: bridging the gap between atomic-level theoretical modeling and reality by total scattering experiments. NANOSCALE 2015; 7:17902-17922. [PMID: 26463562 DOI: 10.1039/c5nr04678e] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The extent to which current theoretical modeling alone can reveal real-world metallic nanoparticles (NPs) at the atomic level was scrutinized and demonstrated to be insufficient and how it can be improved by using a pragmatic approach involving straightforward experiments is shown. In particular, 4 to 6 nm in size silica supported Au(100-x)Pd(x) (x = 30, 46 and 58) explored for catalytic applications is characterized structurally by total scattering experiments including high-energy synchrotron X-ray diffraction (XRD) coupled to atomic pair distribution function (PDF) analysis. Atomic-level models for the NPs are built by molecular dynamics simulations based on the archetypal for current theoretical modeling Sutton-Chen (SC) method. Models are matched against independent experimental data and are demonstrated to be inaccurate unless their theoretical foundation, i.e. the SC method, is supplemented with basic yet crucial information on the length and strength of metal-to-metal bonds and, when necessary, structural disorder in the actual NPs studied. An atomic PDF-based approach for accessing such information and implementing it in theoretical modeling is put forward. For completeness, the approach is concisely demonstrated on 15 nm in size water-dispersed Au particles explored for bio-medical applications and 16 nm in size hexane-dispersed Fe48Pd52 particles explored for magnetic applications as well. It is argued that when "tuned up" against experiments relevant to metals and alloys confined to nanoscale dimensions, such as total scattering coupled to atomic PDF analysis, rather than by mere intuition and/or against data for the respective solids, atomic-level theoretical modeling can provide a sound understanding of the synthesis-structure-property relationships in real-world metallic NPs. Ultimately this can help advance nanoscience and technology a step closer to producing metallic NPs by rational design.
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Affiliation(s)
- Binay Prasai
- Department of Physics, Central Michigan University, Mt. Pleasant, Michigan 48858, USA.
| | - A R Wilson
- Department of Chemistry, Duke University, Durham, NC 27708, USA
| | - B J Wiley
- Department of Chemistry, Duke University, Durham, NC 27708, USA
| | - Y Ren
- X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - Valeri Petkov
- Department of Physics, Central Michigan University, Mt. Pleasant, Michigan 48858, USA.
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18
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Structure and Properties of Silica Glass Densified in Cold Compression and Hot Compression. Sci Rep 2015; 5:15343. [PMID: 26469314 PMCID: PMC4606793 DOI: 10.1038/srep15343] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 09/23/2015] [Indexed: 11/16/2022] Open
Abstract
Silica glass has been shown in numerous studies to possess significant capacity for permanent densification under pressure at different temperatures to form high density amorphous (HDA) silica. However, it is unknown to what extent the processes leading to irreversible densification of silica glass in cold-compression at room temperature and in hot-compression (e.g., near glass transition temperature) are common in nature. In this work, a hot-compression technique was used to quench silica glass from high temperature (1100 °C) and high pressure (up to 8 GPa) conditions, which leads to density increase of ~25% and Young’s modulus increase of ~71% relative to that of pristine silica glass at ambient conditions. Our experiments and molecular dynamics (MD) simulations provide solid evidences that the intermediate-range order of the hot-compressed HDA silica is distinct from that of the counterpart cold-compressed at room temperature. This explains the much higher thermal and mechanical stability of the former than the latter upon heating and compression as revealed in our in-situ Brillouin light scattering (BLS) experiments. Our studies demonstrate the limitation of the resulting density as a structural indicator of polyamorphism, and point out the importance of temperature during compression in order to fundamentally understand HDA silica.
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19
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Ramanan N, Lahiri D, Rajput P, Varma RC, Arun A, Muraleedharan TS, Pandey KK, Maiti N, Jha SN, Sharma SM. Investigating structural aspects to understand the putative/claimed non-toxicity of the Hg-based Ayurvedic drug Rasasindura using XAFS. JOURNAL OF SYNCHROTRON RADIATION 2015; 22:1233-1241. [PMID: 26289275 DOI: 10.1107/s1600577515012473] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 06/29/2015] [Indexed: 06/04/2023]
Abstract
XANES- and EXAFS-based analysis of the Ayurvedic Hg-based nano-drug Rasasindura has been performed to seek evidence of its non-toxicity. Rasasindura is determined to be composed of single-phase α-HgS nanoparticles (size ∼24 nm), free of Hg(0) or organic molecules; its structure is determined to be robust (<3% defects). The non-existence of Hg(0) implies the absence of Hg-based toxicity and establishes that chemical form, rather than content of heavy metals, is the correct parameter for evaluating the toxicity in these drugs. The stable α-HgS form (strong Hg-S covalent bond and robust particle character) ensures the integrity of the drug during delivery and prevention of its reduction to Hg(0) within the human body. Further, these comparative studies establish that structural parameters (size dispersion, coordination configuration) are better controlled in Rasasindura. This places the Ayurvedic synthesis method on par with contemporary techniques of nanoparticle synthesis.
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Affiliation(s)
- Nitya Ramanan
- High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Purnima Labs Trombay, Mumbai, Maharashtra 400085, India
| | - Debdutta Lahiri
- High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Purnima Labs Trombay, Mumbai, Maharashtra 400085, India
| | - Parasmani Rajput
- Atomic and Molecular Physics Division, Bhabha Atomic Research Centre, Purnima Labs Trombay, Mumbai, Maharashtra 400085, India
| | | | - A Arun
- Arya Vaidya Sala, Kottakkal, Kerala 676503, India
| | | | - K K Pandey
- High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Purnima Labs Trombay, Mumbai, Maharashtra 400085, India
| | - Nandita Maiti
- Radiation and Photochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai, Maharashtra 400085, India
| | - S N Jha
- Atomic and Molecular Physics Division, Bhabha Atomic Research Centre, Purnima Labs Trombay, Mumbai, Maharashtra 400085, India
| | - Surinder M Sharma
- High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Purnima Labs Trombay, Mumbai, Maharashtra 400085, India
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20
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Bedford NM, Ramezani-Dakhel H, Slocik JM, Briggs BD, Ren Y, Frenkel AI, Petkov V, Heinz H, Naik RR, Knecht MR. Elucidation of peptide-directed palladium surface structure for biologically tunable nanocatalysts. ACS NANO 2015; 9:5082-92. [PMID: 25905675 DOI: 10.1021/acsnano.5b00168] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Peptide-enabled synthesis of inorganic nanostructures represents an avenue to access catalytic materials with tunable and optimized properties. This is achieved via peptide complexity and programmability that is missing in traditional ligands for catalytic nanomaterials. Unfortunately, there is limited information available to correlate peptide sequence to particle structure and catalytic activity to date. As such, the application of peptide-enabled nanocatalysts remains limited to trial and error approaches. In this paper, a hybrid experimental and computational approach is introduced to systematically elucidate biomolecule-dependent structure/function relationships for peptide-capped Pd nanocatalysts. Synchrotron X-ray techniques were used to uncover substantial particle surface structural disorder, which was dependent upon the amino acid sequence of the peptide capping ligand. Nanocatalyst configurations were then determined directly from experimental data using reverse Monte Carlo methods and further refined using molecular dynamics simulation, obtaining thermodynamically stable peptide-Pd nanoparticle configurations. Sequence-dependent catalytic property differences for C-C coupling and olefin hydrogenation were then elucidated by identification of the catalytic active sites at the atomic level and quantitative prediction of relative reaction rates. This hybrid methodology provides a clear route to determine peptide-dependent structure/function relationships, enabling the generation of guidelines for catalyst design through rational tailoring of peptide sequences.
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Affiliation(s)
- Nicholas M Bedford
- †Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433, United States
- ‡Department of Chemistry, University of Miami, Coral Gables, Florida 33146, United States
| | - Hadi Ramezani-Dakhel
- §Department of Polymer Engineering, University of Akron, Akron, Ohio 44325, United States
| | - Joseph M Slocik
- †Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433, United States
| | - Beverly D Briggs
- ‡Department of Chemistry, University of Miami, Coral Gables, Florida 33146, United States
| | - Yang Ren
- ⊥X-ray Science Division, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Anatoly I Frenkel
- ∥Department of Physics, Yeshiva University, New York, New York 10016, United States
| | - Valeri Petkov
- #Department of Physics, Central Michigan University, Mt. Pleasant, Michigan 48858, United States
| | - Hendrik Heinz
- §Department of Polymer Engineering, University of Akron, Akron, Ohio 44325, United States
| | - Rajesh R Naik
- †Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433, United States
| | - Marc R Knecht
- ‡Department of Chemistry, University of Miami, Coral Gables, Florida 33146, United States
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21
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Prasai B, Ren Y, Shan S, Zhao Y, Cronk H, Luo J, Zhong CJ, Petkov V. Synthesis-atomic structure-properties relationships in metallic nanoparticles by total scattering experiments and 3D computer simulations: case of Pt-Ru nanoalloy catalysts. NANOSCALE 2015; 7:8122-8134. [PMID: 25874741 DOI: 10.1039/c5nr00800j] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
An approach to determining the 3D atomic structure of metallic nanoparticles (NPs) in fine detail and using the unique knowledge obtained for rationalizing their synthesis and properties targeted for optimization is described and exemplified on Pt-Ru alloy NPs of importance to the development of devices for clean energy conversion such as fuel cells. In particular, PtxRu100-x alloy NPs, where x = 31, 49 and 75, are synthesized by wet chemistry and activated catalytically by a post-synthesis treatment involving heating under controlled N2-H2 atmosphere. So-activated NPs are evaluated as catalysts for gas-phase CO oxidation and ethanol electro-oxidation reactions taking place in fuel cells. Both as-synthesized and activated NPs are characterized structurally by total scattering experiments involving high-energy synchrotron X-ray diffraction coupled to atomic pair distribution functions (PDFs) analysis. 3D structure models both for as-synthesized and activated NPs are built by molecular dynamics simulations based on the archetypal for current theoretical modelling Sutton-Chen method. Models are refined against the experimental PDF data by reverse Monte Carlo simulations and analysed in terms of prime structural characteristics such as metal-to-metal bond lengths, bond angles and first coordination numbers for Pt and Ru atoms. Analysis indicates that, though of a similar type, the atomic structure of as-synthesized and respective activated NPs differ in several details of importance to NP catalytic properties. Structural characteristics of activated NPs and data for their catalytic activity are compared side by side and strong evidence found that electronic effects, indicated by significant changes in Pt-Pt and Ru-Ru metal bond lengths at NP surface, and practically unrecognized so far atomic ensemble effects, indicated by distinct stacking of atomic layers near NP surface and prevalence of particular configurations of Pt and Ru atoms in these layers, contribute to the observed enhancement of the catalytic activity of PtxRu100-x alloy NPs at x ∼ 50. Implications of so-established relationships between the atomic structure and catalytic activity of Pt-Ru alloy NPs on efforts aimed at improving further the latter by tuning-up the former are discussed and the usefulness of detailed NP structure studies to advancing science and technology of metallic NPs - exemplified.
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Affiliation(s)
- Binay Prasai
- Department of Physics, Central Michigan University, Mt. Pleasant, Michigan 48858, USA.
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22
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Structural studies on Si-N gradient thin layers by grazing incidence X-ray diffraction. SURF INTERFACE ANAL 2014. [DOI: 10.1002/sia.5487] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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23
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Buscaglia V, Tripathi S, Petkov V, Dapiaggi M, Deluca M, Gajović A, Ren Y. Average and local atomic-scale structure in BaZrxTi(1-x)O3 (x = 0. 10, 0.20, 0.40) ceramics by high-energy x-ray diffraction and Raman spectroscopy. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2014; 26:065901. [PMID: 24441707 DOI: 10.1088/0953-8984/26/6/065901] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
High-resolution x-ray diffraction (XRD), Raman spectroscopy and total scattering XRD coupled to atomic pair distribution function (PDF) analysis studies of the atomic-scale structure of archetypal BaZrxTi(1-x)O3 (x = 0.10, 0.20, 0.40) ceramics are presented over a wide temperature range (100-450 K). For x = 0.1 and 0.2 the results reveal, well above the Curie temperature, the presence of Ti-rich polar clusters which are precursors of a long-range ferroelectric order observed below TC. Polar nanoregions (PNRs) and relaxor behaviour are observed over the whole temperature range for x = 0.4. Irrespective of ceramic composition, the polar clusters are due to locally correlated off-centre displacement of Zr/Ti cations compatible with local rhombohedral symmetry. Formation of Zr-rich clusters is indicated by Raman spectroscopy for all compositions. Considering the isovalent substitution of Ti with Zr in BaZrxTi1-xO3, the mechanism of formation and growth of the PNRs is not due to charge ordering and random fields, but rather to a reduction of the local strain promoted by the large difference in ion size between Zr(4+) and Ti(4+). As a result, non-polar or weakly polar Zr-rich clusters and polar Ti-rich clusters are randomly distributed in a paraelectric lattice and the long-range ferroelectric order is disrupted with increasing Zr concentration.
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Affiliation(s)
- Vincenzo Buscaglia
- Institute for Energetics and Interphases, National Research Council (IENI-CNR), Via De Marini 6, I-16149 Genova, Italy
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24
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Rabuffetti FA, Brutchey RL. Local structure of Ba(1-x)Sr(x)TiO3 and BaTi(1-y)Zr(y)O3 nanocrystals probed by X-ray absorption and X-ray total scattering. ACS NANO 2013; 7:11435-11444. [PMID: 24279651 DOI: 10.1021/nn405629e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The effect of isovalent chemical substitution on the magnitude and coherence length of local ferroelectric distortions present in sub-20 nm Ba(1-x)Sr(x)TiO3 (x = 0.0, 0.30, 0.50, 1.0) and BaTi(1-y)Zr(y)O3 (y = 0.0, 0.15, 0.50, 1.0) nanocrystals synthesized at room temperature is investigated using X-ray absorption near edge structure (XANES) and pair distribution function analysis of X-ray total scattering data (PDF). Although the average crystal structure of the nanocrystals is adequately described by a centrosymmetric, cubic Pm3m space group, local ferroelectric distortions due to the displacement of the titanium atom from the center of the perovskite lattice are observed for all compositions, except BaZrO3. The symmetry of the ferroelectric distortions is adequately described by a tetragonal P4mm space group. The magnitude of the local displacements of the titanium atom in BaTiO3 nanocrystals is comparable to that observed in single crystals and bulk ceramics, but the coherence length of their ferroelectric coupling is much shorter (≤20 Å). Substitution of Sr(2+) for Ba(2+) and of Zr(4+) for Ti(4+) induces a tetragonal-to-cubic transition of the room temperature local crystal structure, analogous to that observed for single crystals and bulk ceramics at similar compositions. This transition is driven by a reduction of the magnitude of the local displacements of the titanium atom and/or of the coherence length of their ferroelectric coupling. Replacing 50% of Ba(2+) with Sr(2+) slightly reduces the magnitude of the titanium displacement, but the coherence length is not affected. In contrast, replacing 15% of the ferroelectrically active Ti(4+) with Zr(4+) leads to a significant reduction of the coherence length. Deviations from the ideal solid solution behavior are observed in BaTi(1-y)Zr(y)O3 nanocrystals and are attributed to an inhomogeneous distribution of the barium atoms in the nanocrystal. Composition-structure relationships derived for Ba(1-x)Sr(x)TiO3 and BaTi(1-y)Zr(y)O3 nanocrystals demonstrate that the evolution of the room temperature local crystal structure with chemical composition parallels that of single crystals and bulk ceramics, and that chemical control over ferroelectric distortions is possible in the sub-20 nm size range. In addition, the potential of PDF analysis of total scattering data to probe compositional fluctuations in nanocrystals is demonstrated.
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Affiliation(s)
- Federico A Rabuffetti
- Department of Chemistry, University of Southern California , Los Angeles, California 90089, United States
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25
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Rabuffetti FA, Culver SP, Suescun L, Brutchey RL. Structural Disorder in AMoO4 (A = Ca, Sr, Ba) Scheelite Nanocrystals. Inorg Chem 2013; 53:1056-61. [DOI: 10.1021/ic4025348] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Federico A. Rabuffetti
- Department
of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Sean P. Culver
- Department
of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Leopoldo Suescun
- Cryssmat−Lab/DETEMA,
Facultad de Química, Universidad de la República, Montevideo, Uruguay
| | - Richard L. Brutchey
- Department
of Chemistry, University of Southern California, Los Angeles, California 90089, United States
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26
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Gereben O, Petkov V. Reverse Monte Carlo study of spherical sample under non-periodic boundary conditions: the structure of Ru nanoparticles based on x-ray diffraction data. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2013; 25:454211. [PMID: 24141235 DOI: 10.1088/0953-8984/25/45/454211] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
A new method to fit experimental diffraction data with non-periodic structure models for spherical particles was implemented in the reverse Monte Carlo simulation code. The method was tested on x-ray diffraction data for ruthenium (Ru) nanoparticles approximately 5.6 nm in diameter. It was found that the atomic ordering in the ruthenium nanoparticles is quite distorted, barely resembling the hexagonal structure of bulk Ru. The average coordination number for the bulk decreased from 12 to 11.25. A similar lack of structural order has been observed with other nanoparticles (e.g. Petkov et al 2008 J. Phys. Chem. C 112 8907-11) indicating that atomic disorder is a widespread feature of nanoparticles less than 10 nm in diameter.
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Affiliation(s)
- Orsolya Gereben
- Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, PO Box 49, H-1525 Budapest, Hungary
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27
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Billinge SJL, Farrow CL. Towards a robust ad hoc data correction approach that yields reliable atomic pair distribution functions from powder diffraction data. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2013; 25:454202. [PMID: 24140913 DOI: 10.1088/0953-8984/25/45/454202] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We examine the equations to obtain atomic pair distribution functions (PDFs) from x-ray, neutron and electron powder diffraction data with a view to obtaining reliable and accurate PDFs from the raw data using a largely ad hoc correction process. We find that this should be possible under certain circumstances that hold, to a reasonably good approximation, in many modern experiments. We describe a variational approach that could be applied to find data correction parameters that is highly automatable and should require little in the way of user inputs yet results in quantitatively reliable PDFs, modulo unknown scale factors that are often not of scientific interest when profile fitting models are applied to the data with scale factor as a parameter. We have worked on a particular implementation of these ideas and demonstrate that it yields PDFs that are of comparable quality to those obtained with the existing x-ray data reduction program PDFgetX2. This opens the door to rapid and highly automated processing of raw data to obtain PDFs.
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Affiliation(s)
- Simon J L Billinge
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, NY 10027, USA. Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory Upton, NY 11973, USA
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28
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Detecting phase separation of freeze-dried binary amorphous systems using pair-wise distribution function and multivariate data analysis. Int J Pharm 2013; 454:167-73. [DOI: 10.1016/j.ijpharm.2013.07.030] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 07/08/2013] [Accepted: 07/12/2013] [Indexed: 11/23/2022]
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29
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Abstract
There is an ongoing interest in nanoparticles for the unique properties that have applications in a range of fields including catalysis, semi-conductors, gas storage amongst many others. In this study a variety of distinct techniques were applied on the same in-house X-Ray diffractometer. In particular, SAXS, conventional XRD and Total Scattering of nano-sized TiO2 powders were performed, together with in-situ heating experiments. The combination of the results from each technique proves to be a powerful tool for a more complete description of the material.
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30
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Juhás P, Davis T, Farrow C, Billinge S. PDFgetX3: a rapid and highly automatable program for processing powder diffraction data into total scattering pair distribution functions. J Appl Crystallogr 2013. [DOI: 10.1107/s0021889813005190] [Citation(s) in RCA: 656] [Impact Index Per Article: 59.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
PDFgetX3is a new software application for converting X-ray powder diffraction data to an atomic pair distribution function (PDF).PDFgetX3has been designed for ease of use, speed and automated operation. The software can readily process hundreds of X-ray patterns within a few seconds and is thus useful for high-throughput PDF studies that measure numerous data sets as a function of time, temperature or other environmental parameters. In comparison to the preceding programs,PDFgetX3requires fewer inputs and less user experience and it can be readily adopted by novice users. The live-plotting interactive feature allows the user to assess the effects of calculation parameters and select their optimum values.PDFgetX3uses anad hocdata correction method, where the slowly changing structure-independent signal is filtered out to obtain coherent X-ray intensities that contain structure information. The output fromPDFgetX3has been verified by processing experimental PDFs from inorganic, organic and nanosized samples and comparing them with their counterparts from a previous established software. In spite of the different algorithm, the obtained PDFs were nearly identical and yielded highly similar results when used in structure refinement.PDFgetX3is written in the Python language and features a well documented reusable code base. The software can be used either as a standalone application or as a library of PDF processing functions that can be called from other Python scripts. The software is free for open academic research but requires paid license for commercial use.
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Polking MJ, Han MG, Yourdkhani A, Petkov V, Kisielowski CF, Volkov VV, Zhu Y, Caruntu G, Alivisatos AP, Ramesh R. Ferroelectric order in individual nanometre-scale crystals. NATURE MATERIALS 2012; 11:700-709. [PMID: 22772655 DOI: 10.1038/nmat3371] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Accepted: 05/29/2012] [Indexed: 05/29/2023]
Abstract
Ferroelectricity in finite-dimensional systems continues to arouse interest, motivated by predictions of vortex polarization states and the utility of ferroelectric nanomaterials in memory devices, actuators and other applications. Critical to these areas of research are the nanoscale polarization structure and scaling limit of ferroelectric order, which are determined here in individual nanocrystals comprising a single ferroelectric domain. Maps of ferroelectric structural distortions obtained from aberration-corrected transmission electron microscopy, combined with holographic polarization imaging, indicate the persistence of a linearly ordered and monodomain polarization state at nanometre dimensions. Room-temperature polarization switching is demonstrated down to ~5 nm dimensions. Ferroelectric coherence is facilitated in part by control of particle morphology, which along with electrostatic boundary conditions is found to determine the spatial extent of cooperative ferroelectric distortions. This work points the way to multi-Tbit/in(2) memories and provides a glimpse of the structural and electrical manifestations of ferroelectricity down to its ultimate limits.
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Affiliation(s)
- Mark J Polking
- Department of Materials Science and Engineering, University of California, Berkeley, Berkeley, California 94720, USA
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Rabuffetti FA, Brutchey RL. Structural Evolution of BaTiO3 Nanocrystals Synthesized at Room Temperature. J Am Chem Soc 2012; 134:9475-87. [DOI: 10.1021/ja303184w] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Federico A. Rabuffetti
- Department of Chemistry, University of Southern California, Los Angeles, California 90089,
United States
| | - Richard L. Brutchey
- Department of Chemistry, University of Southern California, Los Angeles, California 90089,
United States
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Reiss CA, Kharchenko A, Gateshki M. On the use of laboratory X-ray diffraction equipment for Pair Distribution Function (PDF) studies. ACTA ACUST UNITED AC 2012. [DOI: 10.1524/zkri.2012.1492] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Boetker JP, Koradia V, Rades T, Rantanen J, Savolainen M. Atomic pairwise distribution function analysis of the amorphous phase prepared by different manufacturing routes. Pharmaceutics 2012; 4:93-103. [PMID: 24300182 PMCID: PMC3834909 DOI: 10.3390/pharmaceutics4010093] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2011] [Revised: 01/05/2012] [Accepted: 01/19/2012] [Indexed: 11/29/2022] Open
Abstract
Amlodipine besilate, a calcium channel antagonist, exists in several solid forms. Processing of anhydrate and dihydrate forms of this drug may lead to solid state changes, and is therefore the focus of this study. Milling was performed for the anhydrate form, whereas the dihydrate form was subjected to quench cooling thereby creating an amorphous form of the drug from both starting materials. The milled and quench cooled samples were, together with the crystalline starting materials, analyzed with X-ray powder diffraction (XRPD), Raman spectroscopy and atomic pair-wise distribution function (PDF) analysis of the XRPD pattern. When compared to XRPD and Raman spectroscopy, the PDF analysis was superior in displaying the difference between the amorphous samples prepared by milling and quench cooling approaches of the two starting materials.
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Affiliation(s)
- Johan P. Boetker
- Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark; (J.P.B.); (M.S.)
| | - Vishal Koradia
- Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark; (J.P.B.); (M.S.)
| | - Thomas Rades
- School of Pharmacy, University of Otago, 18 Frederick Street, Dunedin 9054, New Zealand;
| | - Jukka Rantanen
- Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark; (J.P.B.); (M.S.)
- Author to whom correspondence should be addressed; ; Tel.: +45-35336585; Fax: +45-35336000
| | - Marja Savolainen
- Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark; (J.P.B.); (M.S.)
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Petkov V, Timmons A, Camardese J, Ren Y. Li insertion in ball-milled graphitic carbon studied by total x-ray diffraction. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2011; 23:435003. [PMID: 21960020 DOI: 10.1088/0953-8984/23/43/435003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Ball-milled graphitic carbon, both not and electrochemically lithiated, has been studied by total x-ray diffraction involving high-energy synchrotron radiation scattering and atomic pair distribution function analysis. The experimental data has been used to guide reverse Monte Carlo simulations of the three-dimensional structure of the not-lithiated samples. Experimental and modeling results show that ball milling for short times breaks the graphitic layers into smaller pieces as well as generates extended atomic vacancies. Those increase the overall ability of the material to accommodate lithium. Ball milling for longer times keeps generating even more atomic vacancies in the graphitic layers. Carbon atoms displaced from the layers, however, move in between the layers, turning heavily ball-milled graphitic carbon into an assembly of almost-fused-together, heavily buckled layers that have an impaired ability to accommodate Li atoms. This helps explain well the initial substantial increase and then decrease in the Li storage capacity of ball-milled graphitic carbon. The study demonstrates the great ability of total x-ray diffraction to provide precise structural information for complex materials that are being increasingly explored for energy applications.
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Affiliation(s)
- Valeri Petkov
- Department of Physics, Central Michigan University, Mount Pleasant, MI 48858, USA.
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Bøtker JP, Karmwar P, Strachan CJ, Cornett C, Tian F, Zujovic Z, Rantanen J, Rades T. Assessment of crystalline disorder in cryo-milled samples of indomethacin using atomic pair-wise distribution functions. Int J Pharm 2011; 417:112-9. [DOI: 10.1016/j.ijpharm.2010.12.018] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2010] [Revised: 12/14/2010] [Accepted: 12/15/2010] [Indexed: 10/18/2022]
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Soper AK, Barney ER. Extracting the pair distribution function from white-beam X-ray total scattering data. J Appl Crystallogr 2011. [DOI: 10.1107/s0021889811021455] [Citation(s) in RCA: 147] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
A general method is described for reducing white-beam X-ray total scattering raw data to the differential scattering cross section and pair distribution function. The method incorporates corrections for X-ray fluorescence,Bremsstrahlungradiation, polarization, attenuation, multiple scattering and sample container scattering, and invokes the Krogh-Moe and Norman method to put the data on an absolute scale. An accurate method to convert the differential scattering cross section to the pair distribution function is also described, and a rigorous and revised Lorch function is proposed for removing the effects of Fourier truncation oscillations. The method can be equally applied to synchrotron X-ray data, where the data analysis can be simpler than at a laboratory source.
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Reibstein S, Wondraczek L, de Ligny D, Krolikowski S, Sirotkin S, Simon JP, Martinez V, Champagnon B. Structural heterogeneity and pressure-relaxation in compressed borosilicate glasses by in situ small angle X-ray scattering. J Chem Phys 2011; 134:204502. [DOI: 10.1063/1.3593399] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
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Roux SL, Martin S, Christensen R, Ren Y, Petkov V. Three-dimensional structure of multicomponent (Na₂O)0.₃₅ [(P₂O₅)₁- x(B₂O₃)x]0.₆₅ glasses by high-energy x-ray diffraction and constrained reverse Monte Carlo simulations. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2011; 23:035403. [PMID: 21406865 DOI: 10.1088/0953-8984/23/3/035403] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Experimental structure functions for (Na(2)O)(0.35) [(P(2)O(5))(1 - x)(B(2)O(3))(x)](0.65) glasses, where x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0, have been measured by high-energy x-ray diffraction up to wavevectors of 28 Å( - 1) to obtain atomic pair distribution functions with high real space resolution. The experimental diffraction data have been used to guide constrained reverse Monte Carlo simulations of the three-dimensional structure of the glasses. The resulting models show that the glasses exhibit a very complex atomic-scale structure that evolves from an assembly of chains of corner shared P(O)(4) tetrahedra for x = 0 to a network of B(O)(4) tetrahedra and planar B(O)(3) units for x = 1. In the glasses of intermediate composition (i.e. 0 < x < 1), P, B and oxygen atoms sit on the vertices of P(O)(4), B(O)(4) and B(O)(3) units mixed in various proportions. Sodium atoms are found to fill up the cavities in between the P/B-oxygen units in a more or less random manner. The new data can provide a firm structural basis for an explanation of the mixed glass former effect where a nonlinear behavior of Na ion conductivity is observed in the (Na(2)O)(0.35) [(P(2)O(5))(1 - x)(B(2)O(3))(x)](0.65) glass system.
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Affiliation(s)
- Sébastien Le Roux
- Department of Physics, 230 Dow Science, Central Michigan University, Mount Pleasant, MI 48859, USA
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Gateshki M, Chen Q, Peng LM, Chupas P, Petkov V. Structure of nanosized materials by high-energy X-ray diffraction: study of titanate nanotubes. ACTA ACUST UNITED AC 2009. [DOI: 10.1524/zkri.2007.222.11.612] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
High-energy X-ray diffraction and atomic Pair Distribution Function analysis are employed to determine the atomic-scale structure of titanate nanotubes. It is found that the nanotube walls are built of layers of Ti–O6 octahedra simular to those observed in crystalline layered titanates. In the nanotubes, however, the layers are bent and not stacked in perfect registry as in the crystal.
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Proffen T, Petkov V, Billinge SJL, Vogt T. Chemical short range order obtained from the atomic pair distribution function. ACTA ACUST UNITED AC 2009. [DOI: 10.1524/zkri.217.2.47.20626] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
Many crystalline materials show chemical short range order and relaxation of neighboring atoms. Local structural information can be obtained by analyzing the atomic pair distribution function (PDF) obtained from powder diffraction data. In this paper, we present the successful extraction of chemical short range order parameters from the x-ray PDF of a quenched Cu3Au sample.
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te Nijenhuis J, Gateshki M, Fransen MJ. Possibilities and limitations of X-ray diffraction using high-energy X-rays on a laboratory system. ACTA ACUST UNITED AC 2009. [DOI: 10.1524/zksu.2009.0023] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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43
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Petkov V, Ren Y, Saratovsky I, Pastén P, Gurr SJ, Hayward MA, Poeppelmeier KR, Gaillard JF. Atomic-scale structure of biogenic materials by total X-ray diffraction: a study of bacterial and fungal MnOx. ACS NANO 2009; 3:441-445. [PMID: 19236083 DOI: 10.1021/nn800653a] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Biogenic materials are produced by microorganisms and are typically found in a nanophase state. As such, they are difficult to characterize structurally. In this report, we demonstrate how high-energy X-ray diffraction and atomic pair distribution function analysis can be used to determine the atomic-scale structures of MnO(x) produced by bacteria and fungi. These structures are well-defined, periodic, and species-specific, built of Mn-O(6) octahedra forming birnessite-type layers and todorokite-type tunnels, respectively. The inherent structural diversity of biogenic material may offer opportunities for practical applications.
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Affiliation(s)
- V Petkov
- Department of Physics, 203 Dow Science, Central Michigan University, Mt. Pleasant, Michigan 48859, USA.
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Soper AK. Joint structure refinement of x-ray and neutron diffraction data on disordered materials: application to liquid water. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2007; 19:335206. [PMID: 21694129 DOI: 10.1088/0953-8984/19/33/335206] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
X-ray diffraction data on liquids and disordered solids often provide useful complementary structural information to neutron diffraction data. Interpretation of the x-ray diffraction pattern, which is produced by scattering from the atomic electrons rather than from the atomic nuclei as in the case of neutron diffraction, is, however, complicated by the Q-dependent electronic form factors, which cause the x-ray diffraction signal to decline rapidly with increasing Q, where Q is the wave vector change in the diffraction experiment. The problem is particularly important in cases such as water where there is a significant molecular polarization caused by charge transfer within the molecule. This means that the electron form factors applicable to the molecule in the condensed environment often deviate from their free atom values. The technique of empirical potential structure refinement (EPSR) is used here to focus on the problem of forming a single atomistic structural model which is simultaneously consistent with both x-ray and neutron diffraction data. The case of liquid water is treated explicitly. It is found that x-ray data for water do indeed provide a powerful constraint on possible structural models, but that the Q-range of the different x-ray data sets (maximum Q ranges from 10.8 to ∼17.0 Å(-1) for different x-ray experiments), combined with variations between different data sets, means that it is not possible to rigorously define the precise position and height of the first peak in the OO radial distribution function. Equally, it is found that two different neutron datasets on water, although measured to a maximum Q of at least 30 Å(-1), give rise to further small uncertainties in the position of the hydrogen bond peaks. One general conclusion from the combined use of neutron and x-ray data is that many of the classical water potentials may have a core which is too repulsive at short distances. This produces too sharp a peak in r-space at too short a distance. A softer core potential is proposed here.
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Affiliation(s)
- A K Soper
- ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX, UK
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Bérubé JF, Gagnon K, Fortin D, Decken A, Harvey PD. Solution and Solid-State Properties of Luminescent M−M Bond-Containing Coordination/Organometallic Polymers Using the RNC-M2(dppm)2-CNR Building Blocks (M = Pd, Pt; R = Aryl, Alkyl). Inorg Chem 2006; 45:2812-23. [PMID: 16562938 DOI: 10.1021/ic0509480] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Two families of organometallic polymers built upon the bimetallic M2(dppm)2L(2)2+ fragments (M = Pd, Pt; dppm = bis(diphenylphosphino)methane, L = 1,4-diisocyano-2,3,5,6-tetramethylbenzene (diiso), 1,8-diisocyano-p-menthane (dmb), 1-isocyano-2,6-dimethylbenzene, 1-isocyano-4-isopropylbenzene, and tert-butylisocyanide) were synthesized and fully characterized (1H and 31P NMR, X-ray crystallography (model compounds), IR, Raman, chem. anal., TGA, DSC, powder XRD, 31P NMR T1 and NOE, light scattering, and conductivity measurements). Evidence for polymers in the solid state is provided from the swelling of the polymers upon dissolution and the formation of stand-alone films. However, these species become small oligomers when dissolved. The materials are luminescent in the solid state at 298 and 77 K and in PrCN solution at 77 K. These emissions result from triplet 3(d sigma d sigma*) states despite the presence of low-lying pi-pi* MO levels according to DFT calculations for the aryl isocyanide model compounds. The emission band maxima are located between 640 and 750 nm and exhibit lifetimes of 3-6 ns for the Pd species and 3-4 micros for the Pt analogues in PrCN solution at 77 K. No evidence of intramolecular excitonic photoprocesses was found in any of the polymers.
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Petkov V, Parvanov V, Trikalitis P, Malliakas C, Vogt T, Kanatzidis MG. Three-dimensional structure of nanocomposites from atomic pair distribution function analysis: study of polyaniline and (polyaniline)(0.5)V(2)O(5) x 1.0 H(2)O. J Am Chem Soc 2005; 127:8805-12. [PMID: 15954787 DOI: 10.1021/ja051315n] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The three-dimensional structures of emeraldine base polyaniline (PANI) and (polyaniline)(0.5)V(2)O(5) x 1.0 H(2)O have been determined by total X-ray scattering experiments. Atomic pair distribution functions (PDF) were measured to obtain experimental observables against which structural models were tested and refined. The PDF approach is necessary because of the limited structural coherence in these nanostructured materials. Polyaniline possesses a well-defined local atomic arrangement that can be described in terms of an 84-atom orthorhombic unit cell. The nanocomposite (PANI)(0.5)V(2)O(5) x 1.0 H(2)O too is locally well ordered and may be described in terms of a small number of structure-sensible parameters. The PDF approach allows the construction of structure models of PANI and (PANI)(0.5)V(2)O(5) x 1.0 H(2)O on the basis of which important materials' properties can be explained predicted and possibly improved.
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Affiliation(s)
- Valeri Petkov
- Department of Physics, Central Michigan University, Mt. Pleasant, Michigan 48859, USA.
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Billinge SJL, McKimmy EJ, Shatnawi M, Kim H, Petkov V, Wermeille D, Pinnavaia TJ. Mercury Binding Sites in Thiol-Functionalized Mesostructured Silica. J Am Chem Soc 2005; 127:8492-8. [PMID: 15941284 DOI: 10.1021/ja0506859] [Citation(s) in RCA: 118] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Thiol-functionalized mesostructured silica with anhydrous compositions of (SiO(2))(1)(-)(x)()(LSiO(1.5))(x)(), where L is a mercaptopropyl group and x is the fraction of functionalized framework silicon centers, are effective trapping agents for the removal of mercuric(II) ions from water. In the present work, we investigate the mercury-binding mechanism for representative thiol-functionalized mesostructures by atomic pair distribution function (PDF) analysis of synchrotron X-ray powder diffraction data and by Raman spectroscopy. The mesostructures with wormhole framework structures and compositions corresponding to x = 0.30 and 0.50 were prepared by direct assembly methods in the presence of a structure-directing amine porogen. PDF analyses of five mercury-loaded compositions with Hg/S ratios of 0.50-1.30 provided evidence for the bridging of thiolate sulfur atoms to two metal ion centers and the formation of chain structures on the pore surfaces. We find no evidence for Hg-O bonds and can rule out oxygen coordination of the mercury at greater than the 10% level. The relative intensities of the PDF peaks corresponding to Hg-S and Hg-Hg atomic pairs indicate that the mercury centers cluster on the functionalized surfaces by virtue of thiolate bridging, regardless of the overall mercury loading. However, the Raman results indicate that the complexation of mercury centers by thiolate depends on the mercury loading. At low mercury loadings (Hg/S < or = 0.5), the dominant species is an electrically neutral complex in which mercury most likely is tetrahedrally coordinated to bridging thiolate ligands, as in Hg(SBu(t))(2). At higher loadings (Hg/S 1.0-1.3), mercury complex cations predominate, as evidenced by the presence of charge-balancing anions (nitrate) on the surface. This cationic form of bound mercury is assigned a linear coordination to two bridging thiolate ligands.
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Affiliation(s)
- Simon J L Billinge
- Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824, USA
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Petkov V. Atomic-scale structure of nanocrystals by the atomic pair distribution function technique. MOLECULAR SIMULATION 2005. [DOI: 10.1080/08927020412331308485] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Petkov V, Gateshki M, Choi J, Gillan EG, Ren Y. Structure of nanocrystalline GaN from X-ray diffraction, Rietveld and atomic pair distribution function analyses. ACTA ACUST UNITED AC 2005. [DOI: 10.1039/b509577h] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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50
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Draper ND, Batchelor RJ, Aguiar PM, Kroeker S, Leznoff DB. Factors Affecting the Solid-State Structure and Dimensionality of Mercury Cyanide/Chloride Double Salts, and NMR Characterization of Coordination Geometries. Inorg Chem 2004; 43:6557-67. [PMID: 15476352 DOI: 10.1021/ic049792e] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In the reaction of organic monocationic chlorides or coordinatively saturated metal-ligand complex chlorides with linear, neutral Hg(CN)(2) building blocks, the Lewis-acidic Hg(CN)(2) moieties accept the chloride ligands to form mercury cyanide/chloride double salt anions that in several cases form infinite 1-D and 2-D arrays. Thus, [PPN][Hg(CN)(2)Cl].H(2)O (1), [(n)Bu(4)N][Hg(CN)(2)Cl].0.5 H(2)O (2), and [Ni(terpy)(2)][Hg(CN)(2)Cl](2) (4) contain [Hg(CN)(2)Cl](2)(2-) anionic dimers ([PPN]Cl = bis(triphenylphosphoranylidene)ammonium chloride, [(n)Bu(4)N]Cl = tetrabutylammonium chloride, terpy = 2,2':6',6' '-terpyridine). [Cu(en)(2)][Hg(CN)(2)Cl](2) (5) is composed of alternating 1-D chloride-bridged [Hg(CN)(2)Cl](n)(n-) ladders and cationic columns of [Cu(en)(2)](2+) (en = ethylenediamine). When [Co(en)(3)]Cl(3) is reacted with 3 equiv of Hg(CN)(2), 1-D [[Hg(CN)(2)](2)Cl](n)(n-) ribbons and [Hg(CN)(2)Cl(2)](2-) moieties are formed; both form hydrogen bonds to [Co(en)(3)](3+) cations, yielding [Co(en)(3)][Hg(CN)(2)Cl(2)][[Hg(CN)(2)](2)Cl] (6). In [Co(NH(3))(6)](2)[Hg(CN)(2)](5)Cl(6).2H(2)O (7), [Co(NH(3))(6)](3+) cations and water molecules are sandwiched between chloride-bridged 2-D anionic [[Hg(CN)(2)](5)Cl(6)](n)(6n-) layers, which contain square cavities. The presence (or absence), number, and profile of hydrogen bond donor sites of the transition metal amine ligands were observed to strongly influence the structural motif and dimensionality adopted by the anionic double salt complex anions, while cation shape and cation charge had little effect. (199)Hg chemical shift tensors and (1)J((13)C,(199)Hg) values measured in selected compounds reveal that the NMR properties are dominated by the Hg(CN)(2) moiety, with little influence from the chloride bonding characteristics. delta(iso)((13)CN) values in the isolated dimers are remarkably sensitive to the local geometry.
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Affiliation(s)
- Neil D Draper
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia V5A 1S6, Canada
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