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Huang Z.,University of California at Los Angeles | Huang Z.,Carl Zeiss GmbH | Bartels M.,University of Gottingen | Xu R.,University of California at Los Angeles | And 9 more authors.
Nature Materials | Year: 2015

In situ X-ray diffraction (XRD) and transmission electron microscopy (TEM) have been used to investigate many physical science phenomena, ranging from phase transitions, chemical reactions and crystal growth to grain boundary dynamics. A major limitation of in situ XRD and TEM is a compromise that has to be made between spatial and temporal resolution. Here, we report the development of in situ X-ray nanodiffraction to measure high-resolution diffraction patterns from single grains with up to 5 ms temporal resolution. We observed, for the first time, grain rotation and lattice deformation in chemical reactions induced by X-ray photons: Br- + hv → Br + e- and e- + Ag+ → Ag0. The grain rotation and lattice deformation associated with the chemical reactions were quantified to be as fast as 3.25 rad s-1 and as large as 0.5 Å, respectively. The ability to measure high-resolution diffraction patterns from individual grains with a temporal resolution of several milliseconds is expected to find broad applications in materials science, physics, chemistry and nanoscience. © 2015 Macmillan Publishers Limited. Source

Burnett J.D.,Duquesne University | Gourdon O.,Oak Ridge National Laboratory | Gourdon O.,International Center for Diffraction Data | Ranmohotti K.G.S.,University of Michigan | And 4 more authors.
Materials Chemistry and Physics | Year: 2014

CuIn1-xFexS2 (x = 0-0.15) was synthesized via high-temperature, solid-state synthesis. Rietveld refinements using the neutron and synchrotron powder diffraction data indicate that all Fe-substituted materials are phase pure with the exception of the CuIn0.85Fe 0.15S2 sample, which contains a minute secondary phase. These refinements also verify that iron resides on the indium site in the CuIn1-xFexS2 materials. CuIn 0.875Fe0.125S2 displayed the lowest total thermal conductivity of the series, 1.37 W m-1 K-1 at 570 K, as well as the highest thermopower, -172 μV K-1 at 560 K. The electrical conductivity increases over six times upon going from CuInS 2 to CuIn0.875Fe0.125S2. These improved properties result in an increase in the thermoelectric figure of merit (ZT) of CuInS2 by over an order of magnitude for the x = 0.125 sample. Magnetic measurements reveal the x = 0-0.10 samples to be paramagnetic, while the sample in which x = 0.125 displays ferromagnetic ordering below 95 K. © 2014 Elsevier B.V. All rights reserved. Source

Blanton T.,International Center for Diffraction Data
Spectroscopy (Santa Monica) | Year: 2016

Heading into the 2016 Denver Xray Conference in Chicago this July, we asked several leading scientists, all of whom who will be speaking at the conference, to discuss recent developments and trends in Xray fluorescence (XRF) and Xray diffraction (XRD) techniques. Below, Tanja Paunesku of Northwestern University, John A. Anzelmo of Anzelmo & Associates, Carlos R. Appoloni of the State University of Londrina in Brazil, Herbert Poellmann of the University of Halle in Germany, and Tom Blanton of the International Centre for Diffraction Data discuss various aspects of their work with these techniques, including developments in XRF microscopy, advances in sample preparation for XRF, the role of XRF in cultural heritage studies, the use of XRD in the analysis of highperformance building materials, and recent progress in twodimensional XRD detection. © 2016 Advanstar Communications, Inc. All rights reserved. Source

Rianasari I.,United Arab Emirates University | Weston J.,United Arab Emirates University | Rowshan R.,United Arab Emirates University | Blanton T.,International Center for Diffraction Data | And 2 more authors.
Journal of Applied Polymer Science | Year: 2015

We report the formation of cohesive, mechanically robust thin films of Teflon-AF formed via self-assembly of nanoparticles at both air/water and oil/water interfaces of micro-emulsion droplets. We also present results of morphological and mechanical investigations of thin films formed at these oil/water interfaces. Scanning electron microscope and low angle X-ray diffraction characterization of drop cast thin films from the micro-emulsions showed the presence of stacks of nanosheets with an average thickness of 6 nm. Atomic force microscopy (AFM) characterization put the thickness at a much lower value of around 2 nm implying that these sheets are comprised of molecular sheets of Teflon-AF. AFM characterization also indicated that these sheets are stretched molecular films comprising inter-diffused molecular chains, arranged in a regular fashion. Nanoindentation studies of these films unambiguously demonstrated the "tablet sliding" mechanism, similar to nacre, for dissipating applied stress. © 2014 Wiley Periodicals, Inc. Source

Khapli S.,Abu Dhabi University | Rianasari I.,Abu Dhabi University | Sharma S.,Abu Dhabi University | Blanton T.,International Center for Diffraction Data | Jagannathan R.,Abu Dhabi University
Materials Today: Proceedings | Year: 2016

We report a versatile method for the fabrication of hierarchically structured porous ceramic films through a non-vacuum, aerosol-based deposition technique. Our method consists of evaporation of CO2-enriched water microdroplets containing dissolved organic salts and yields a variety of porous scaffolds with micron-sized pores. In addition, the films are characterized by a hierarchy of structural features, such as nanowires, nanorods, 2-dimensional crystals, or nanopores. This scalable, environment-friendly method is applicable to a wide variety of ceramic materials and can lead to materials with an improved performance in catalysis, sensors, solar cells, fuel cells, and tissue engineering. © 2016 Elsevier Ltd. Source

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