A5001983179- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Ferroelectric and Piezoelectric Materials
- Advancements in Solid Oxide Fuel Cells
- Nuclear materials and radiation effects
- Electronic and Structural Properties of Oxides
- Magnetic and transport properties of perovskites and related materials
- Advanced ceramic materials synthesis
- Advanced Condensed Matter Physics
- Microwave Dielectric Ceramics Synthesis
- Glass properties and applications
- Multiferroics and related materials
- Physics of Superconductivity and Magnetism
- Radioactive element chemistry and processing
- Crystal Structures and Properties
- Chemical Synthesis and Characterization
- Crystallography and molecular interactions
- Semiconductor materials and devices
- Rare-earth and actinide compounds
- High-pressure geophysics and materials
- Catalytic Processes in Materials Science
- Advancements in Battery Materials
- Catalysis and Oxidation Reactions
- Quasicrystal Structures and Properties
- Titanium Alloys Microstructure and Properties
Alfred University
2016-2025
New York State College of Ceramics
2007-2023
Oak Ridge National Laboratory
1996-2018
City University of Hong Kong
2018
Forschungszentrum Jülich
2018
Argonne National Laboratory
2016
University of Insubria
2016
Institute of Crystallography
2016
Institute of Physics
2016
Chinese Academy of Sciences
2016
Abstract 3D porous nanostructures built from 2D δ-MnO 2 nanosheets are an environmentally friendly and industrially scalable class of supercapacitor electrode material. While both the electrochemistry defects this material have been studied, role in improving energy storage density these materials has not addressed. In work, nanosheet assemblies with 150 m g −1 specific surface area prepared by exfoliation crystalline K x MnO subsequent reassembly. Equilibration at different pH introduces...
Ni‐rich layered oxides (LiNi 1– x M O 2 ; = Co, Mn, …) are appealing alternatives to conventional LiCoO as cathodes in Li‐ion batteries for automobile and other large‐scale applications due their high theoretical capacity low cost. However, preparing stoichiometric LiNi with ordered layer structure reversible capacity, has proven difficult cation mixing octahedral sites. Herein, situ studies of synthesis reactions the associated structural ordering LiNiO Co‐substituted variant, 0.8 Co 0.2 ,...
Roughness of a surface as characterized by an atomic force microscope (AFM) is typically expressed using conventional statistical measurements including root-mean-square, peak-to-valley ratio, and average roughness. However, in these only the vertical distribution roughness (z-axis) considered. Additionally, determined AFM function scanning scale, sampling interval and/or methods; therefore, consideration quantification lateral (x y) necessary. Power spectral density (PSD) analysis provides...
This perspective focuses on the synthesis, characterization, and modeling of three classes hierarchical materials with potential for sequestering radionuclides: nanoparticles, porous frameworks, crystalline salt inclusion phases. The scientific impact structures development underlying crystal chemistry is discussed as laying groundwork design, local structure control, synthesis new forms matter tailored properties. requires necessary understanding such complex through integrated studies that...
A new approach to intentionally induce phase transition of Li‐excess layered cathode materials for high‐performance lithium ion batteries is reported. In high contrast the limited layered‐to‐spinel transformation that occurred during in situ electrochemical cycles, a Li[Li 0.2 Mn 0.54 Ni 0.13 Co ]O 2 completely converted Li 4 5 O 12 ‐type spinel product via ex ion‐exchanges and post‐annealing process. Such conversion examined using X‐ray diffraction high‐resolution transmission electron...
Thermodynamic studies of actinide-containing metal-organic frameworks (An-MOFs), reported herein for the first time, are a step toward addressing challenges related to effective nuclear waste administration. In addition An-MOF thermochemistry, enthalpies formation were determined organic linkers, 2,2'-dimethylbiphenyl-4,4'-dicarboxylic acid (H2Me2BPDC) and biphenyl-4,4'-dicarboxylic (H2BPDC), which commonly used building blocks MOF preparation. The electronic structure example with...
Copper-based chalcogenides have emerged as promising thermoelectric materials due to their high performance, tunable transport properties, earth abundance and low toxicity. We presented an overview of experimental results first-principal calculations investigating the properties various polymorphs Cu2SnS3 (CTS), Cu2ZnSnS4 (CZTS), Cu2ZnSnSe4 (CZTSe) synthesized by high-energy reactive mechanical alloying (ball milling). Of particular interest are disordered these materials, which exhibit...
The desorption of hydrogen from a novel material, Ti45Zr38Ni17-H quasicrystal, was observed using high-temperature powder x-ray diffraction, demonstrating the potential utility Ti-based quasicrystals in place crystalline or amorphous hydrides for storage applications. maximum change concentration 61 at. %, corresponding to hydrogen-to-metal ratio (H/M) 1.54, at 91 °C less than 2.5 % (H/M=0.025) 620 °C. onset temperature is below 350 Surface oxidation found promote formation hydride phases....
Silver sulfide, Ag 2 S, is most commonly known as the tarnish that forms on silver surfaces due to exposure of hydrogen sulfide. The mineral acanthite a monoclinic crystalline form S stable 176°C. Upon heating above 176°C, there phase conversion body-centered cubic (bcc) referred argentite. Further 586°C results in bcc face-centered (fcc) polymorph. Both high-temperature phases are solid-state ion conductors. In situ X-ray diffraction was used better understand polymorphs heating. existing...
The α , β γ and δ polymorphs of Y 2 Si O 7 were synthesized using sol-gel solid-state methods. structures the determined by identification isostructural rare-earth disilicates, refined Rietveld analysis X-ray powder diffraction data. polymorph crystallizes in space group P 1 with a =6.5872(6) Å, b =6.6387(7) c =12.032(1) =94.501(7)°, =90.984(8)°, =91.771(7)°, volume=524.16(9) Å 3 . form is described / =4.68824(5) =10.84072(9) =5.58219(6) =96.0325(3)°. anisotropic thermal expansion each phase...
High-perfection Ni/Co spinel microcrystalline catalysts with extensive faceting show high turnover frequencies in methane dry reforming and good sulfur tolerance.
Comparison of defect-controlled leaching-kinetics modulation metal–organic frameworks (MOFs) and porous functionalized silica-based materials was performed on the example a radionuclide surrogate for first time, revealing an unprecedented readsorption phenomenon. On series zirconium-based MOFs as model systems, we demonstrated ability to capture retain >99% transuranic 241Am after 1 week storage. We report possibility tailoring release kinetics in through framework defects function...
Neutron diffraction, thermogravimetry, and high temperature solution calorimetry measurements reveal insights into proton oxygen-ion kinetics in BaCo 0.4 Fe Zr 0.2− X Y O 3− δ triple ionic–electronic conducting ceramics.
Separation of size and strain effects on diffraction line profiles has been studied in a round robin involving laboratory instruments synchrotron radiation beamlines operating with different radiation, optics, detectors experimental configurations. The sample, an extensively ball milled iron alloy powder, provides ideal test case, as domain broadening are comparable size. high energy available at some the best conditions for accurate analysis profiles, size–strain separation clearly benefits...
Detailed studies of the absorption and storage hydrogen by icosahedral quasicrystalline Ti-Zr-Ni are presented. Two different methods, one at room temperature another requiring elevated temperatures, successfully introduce into alloys. Absorption is accompanied an expansion quasilattice, results correlating rate to concentration The rates suggest that a surface oxide layer acts as barrier this confirmed depth profiling made with scanning Auger spectroscopy. Desorption also indicate some...
Highly textured PMN‐28PT (0.72Pb(Mg 1/3 Nb 2/3 )O 3 –0.28PbTiO ) ceramics were produced by templated grain growth on <001> oriented platelet‐shaped SrTiO template particles with an aspect ratio of 10–15. The templates aligned in matrix powder via tape casting and fired O 2 –PbO atmosphere at 1150°C for up to 15 h. This resulted a 40 micrometer size without residual templates. volume fraction material ( f the orientation parameter r quantified fitting X‐ray diffraction rocking curve...