478 results on '"John B. Parise"'
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2. Structural Chemistry of Akdalaite, Al10O14(OH)2, the Isostructural Aluminum Analogue of Ferrihydrite
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John B. Parise, Bingying Xia, Jack W. Simonson, William R. Woerner, Anna M. Plonka, Brian L. Phillips, and Lars Ehm
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akdalaite ,ferrihydrite ,solution synthesis ,X-ray diffraction ,NMR spectroscopy ,bond valence sums ,Crystallography ,QD901-999 - Abstract
As part of an effort to characterize clusters and intermediate phases likely to be encountered along solution reaction pathways that produce iron and aluminum oxide-hydroxides from Fe and Al precursors, the complete structure of Al10O14(OH)2 (akdalaite) was determined from a combination of single-crystal X-ray diffraction (SC-XRD) data collected at 100 K to define the Al and O positions, and solid-state nuclear magnetic resonance (NMR) and neutron powder diffraction (NPD) data collected at room temperature (~300 K) to precisely determine the nature of hydrogen in the structure. Two different synthesis routes produced different crystal morphologies. Using an aluminum oxyhydroxide floc made from mixing AlCl3 and 0.48 M NaOH, the product had uniform needle morphology, while using nanocrystalline boehmite (Vista Chemical Company Catapal D alumina) as the starting material produced hexagonal plates. Akdalaite crystallizes in the space group P63mc with lattice parameters of a = 5.6244(3) Å and c = 8.8417(3) Å (SC-XRD) and a = 5.57610(2) Å and c = 8.77247(6) Å (NPD). The crystal structure features Al13O40 Keggin clusters. The structural chemistry of akdalaite is nonideal but broadly conforms to that of ferrihydrite, the nanomineral with which it is isostructural.
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- 2019
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3. Theoretical and Experimental Investigations into Novel Oxynitride Discovery in the GaN-TiO2 System at High Pressure
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Alwin James, M. Mahdi Davari Esfahani, William R. Woerner, Alexandra Sinclair, Lars Ehm, Artem R. Oganov, and John B. Parise
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oxynitrides ,water splitting ,high pressure ,crystal structure prediction ,USPEX ,Crystallography ,QD901-999 - Abstract
We employed ab initio evolutionary algorithm USPEX to speed up the discovery of a novel oxynitride in the binary system of GaN-TiO2 using high-pressure synthesis. A 1:2 mixture of GaN and nanocrystalline TiO2 (anatase) was reacted under 1 GPa of pressure and at 1200 °C in a piston cylinder apparatus to produce a mixture of TiO2 (rutile) and an unknown phase. From the initial analysis of high resolution neutron and X-ray diffraction data, it is isomorphic with monoclinic V2GaO5 with a unit cell composition of Ga10Ti8O28N2 with the following parameters: monoclinic, space group C2/m, a = 17.823(1) Å, b = 2.9970(1) Å, c = 9.4205(5) Å, β = 98.446(3)°; Volume = 497.74(3) Å3. Further, a joint rietveld refinement revealed two distinct regimes—A Ti-rich block and a Ga-rich block. The Ti-rich block consists of four edge-shared octahedra and contains a site which is about 60% occupied by N; this site is bonded to four Ti. The remainder of the block consists of edge linked Ti-octahedral chains linked to the TiN/TiO fragments at octahedral corners partially occupied by nitrogen. The Ga-block contains two symmetry independent octahedral sites, occupied mostly by Ga, and a pure Ga-centered tetrahedral site bonded mostly to oxygen.
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- 2018
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4. Poly[bis(N,N-dimethylformamide-κO)(μ4-naphthalene-1,5-disulfonato)magnesium(II)]
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Lauren A. Borkowski, Debasis Banerjee, and John B. Parise
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Crystallography ,QD901-999 - Abstract
The structure of the title compound, [Mg(C10H6O6S2)(C3H7NO)2]n, consists of MgO6 octahedra (overline{1} symmetry) connected to naphthalene-1,5-disulfonate ligands (overline{1} symmetry) in the equatoral plane, forming a two-dimensional network propagating parallel to (010). The coordination sphere of the Mg atom is completed by the O atoms of two N,N-dimethylformamide (DMF) molecules in the axial positions. The title compound represents the first time the naphthalene-1,5-disulfonate anion is bound directly to a Mg2+ atom. Disorder over two positions was found in the DMF molecule in a 0.518 (8):0.482 (8) ratio.
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- 2010
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5. Anomalous Lattice Thermal Conductivity in Rocksalt IIA–VIA Compounds
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S. C. Rakesh Roshan, N. Yedukondalu, Rajmohan Muthaiah, Kunduru Lavanya, Pazhedath Anees, Rajaboina Rakesh Kumar, Tumu Venkatappa Rao, Lars Ehm, and John B. Parise
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Materials Chemistry ,Electrochemistry ,Energy Engineering and Power Technology ,Chemical Engineering (miscellaneous) ,Electrical and Electronic Engineering - Published
- 2021
6. Lattice Instability and Ultralow Lattice Thermal Conductivity of Layered PbIF
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N. Yedukondalu, Aamir Shafique, S. C. Rakesh Roshan, Mohamed Barhoumi, Rajmohan Muthaiah, Lars Ehm, John B. Parise, and Udo Schwingenschlögl
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Condensed Matter - Materials Science ,Materials Science (cond-mat.mtrl-sci) ,FOS: Physical sciences ,General Materials Science - Abstract
Understanding the interplay between various design strategies (for instance, bonding heterogeneity and lone pair induced anharmonicity) to achieve ultralow lattice thermal conductivity ($\kappa_l$) is indispensable for discovering novel functional materials for thermal energy applications. In the present study, we investigate layered PbXF (X = Cl, Br, I), which offers bonding heterogeneity through the layered crystal structure, anharmonicity through the Pb$^{2+}$ $6s^2$ lone pair, and phonon softening through the mass difference between F and Pb/X. The weak inter-layer van der Waals bonding and the strong intra-layer ionic bonding with partial covalent bonding result in a significant bonding heterogeneity and a poor phonon transport in the out-of-plane direction. Large average Gr\"uneisen parameters ($\geq$ 2.5) demonstrate strong anharmonicity. The computed phonon dispersions show flat bands, which suggest short phonon lifetimes, especially for PbIF. Enhanced Born effective charges are due to cross-band-gap hybridization. PbIF shows lattice instability at a small volume expansion of 0.1$\%$. The $\kappa_l$ values obtained by the two channel transport model are 20-50$\%$ higher than those obtained by solving the Boltzmann transport equation. Overall, ultralow $\kappa_l$ values are found at 300 K, especially for PbIF. We propose that the interplay of bonding heterogeneity, lone pair induced anharmonicity, and constituent elements with high mass difference aids the design of low $\kappa_l$ materials for thermal energy applications.
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- 2022
7. Structural, Vibrational, and Electronic Properties of 1D-TlInTe2 under High Pressure: A Combined Experimental and Theoretical Study
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Kanishka Biswas, Raimundas Sereika, Jie Huang, Curtis Kenney-Benson, Yang Ding, Sorb Yesudhas, Ho-kwang Mao, Jianbo Zhang, John B. Parise, Hong Xiao, Bijuan Chen, Stanislav V. Sinogeikin, Hongshang Deng, N. Yedukondalu, and Manoj K. Jana
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Superconductivity ,Diffraction ,Phase transition ,Condensed matter physics ,010405 organic chemistry ,Phonon ,Chemistry ,Electron ,Electronic structure ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Crystal structure prediction ,Inorganic Chemistry ,Condensed Matter::Materials Science ,symbols.namesake ,Condensed Matter::Superconductivity ,symbols ,Physical and Theoretical Chemistry ,Raman spectroscopy - Abstract
Analogous to 2D layered transition-metal dichalcogenides, the TlSe family of quasi-one dimensional chain materials with the Zintl-type structure exhibits novel phenomena under high pressure. In the present work, we have systematically investigated the high-pressure behavior of TlInTe2 using Raman spectroscopy, synchrotron X-ray diffraction (XRD), and transport measurements, in combination with first principles crystal structure prediction (CSP) based on evolutionary approach. We found that TlInTe2 undergoes a pressure-induced semiconductor-to-semimetal transition at 4 GPa, followed by a superconducting transition at 5.7 GPa (with Tc = 3.8 K). An unusual giant phonon mode (Ag) softening appears at ∼10-12 GPa as a result of the interaction of optical phonons with the conduction electrons. The high-pressure XRD and Raman spectroscopy studies reveal that there is no structural phase transitions observed up to the maximum pressure achieved (33.5 GPa), which is in agreement with our CSP calculations. In addition, our calculations predict two high-pressure phases above 35 GPa following the phase transition sequence as I4/mcm (B37) → Pbcm → Pm3m (B2). Electronic structure calculations suggest Lifshitz (L1 & L2-type) transitions near the superconducting transition pressure. Our findings on TlInTe2 open up a new avenue to study unexplored high-pressure novel phenomena in TlSe family induced by Lifshitz transition (electronic driven), giant phonon softening, and electron-phonon coupling.
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- 2021
8. Probing Phase Transitions and Magnetism in Minerals with Neutrons
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John B. Parise and Bryan C. Chakoumakos
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Phase transition ,Materials science ,Condensed matter physics ,Geochemistry and Petrology ,Magnetism ,Earth and Planetary Sciences (miscellaneous) ,Neutron - Abstract
The development of sophisticated sample environments to control temperature, pressure, and magnetic field has grown in parallel with neutron source and instrumentation development. High-pressure apparatus, with high- and low-temperature capability, novel designs for diamond cells, and large volume presses are matched with next-generation neutron sources and moderator designs to provide unprecedented neutron beam brightness. Recent developments in sample environments are expanding the pressure–temperature space accessible to neutron scattering experiments. Researchers are using new capabilities and an increased understanding of the fundamentals of structural and magnetic transitions to explore new territories, including hydrogenous minerals (e.g., ices and hydrates) and magnetic structural phase diagrams.
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- 2021
9. Resolving Single-layer Nanosheets as Short-lived Intermediates in the Solution Synthesis of FeS
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Michelle L. Beauvais, Karena W. Chapman, John B. Parise, Daniel O'Nolan, and Peter J. Chupas
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Materials science ,Scale (ratio) ,Chemical engineering ,General Chemical Engineering ,Biomedical Engineering ,food and beverages ,General Materials Science ,Reaction intermediate ,Solution synthesis ,Single layer ,Characterization (materials science) ,Material synthesis - Abstract
Short-lived reaction intermediates play a critical role in mediating material synthesis. Such short-lived species often elude characterization because of the mismatch between the time scale of meas...
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- 2021
10. In situ formation of coestite under hydrothermal conditions
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Martin Wilding, Craig L. Bull, Christopher J. Ridley, and John B. Parise
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In situ ,Materials science ,High pressure ,0103 physical sciences ,Neutron diffraction ,Analytical chemistry ,010502 geochemistry & geophysics ,010306 general physics ,Condensed Matter Physics ,01 natural sciences ,Hydrothermal circulation ,Mantle (geology) ,0105 earth and related environmental sciences - Abstract
We present the in situ neutron diffraction data of a water and silica mixture at high pressure and temperature. We show initially the formation of ice VI at 1.5 GPa at 290 K in the presence of crys...
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- 2020
11. Lattice Instability and Raman Spectra of Bao Under High Pressure: A First Principles Study
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K. Lavanya, N. Yedukondalu, S. C. Rakesh Roshan, Shweta D. Dabhi, Suresh Sripada, M. Sainath, Lars Ehm, and John B. Parise
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History ,Polymers and Plastics ,Business and International Management ,Industrial and Manufacturing Engineering - Published
- 2022
12. Compressional behavior of end-member and aluminous iron-bearing diopside at high pressure from single-crystal X-ray diffraction and first principles calculations
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John B. Parise, Baikuntha N. Sahu, Yi Hu, Jin S. Zhang, Murli H. Manghnani, Boris Kiefer, Przemyslaw Dera, and Anna M. Plonka
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Bulk modulus ,Diopside ,010504 meteorology & atmospheric sciences ,Chemistry ,Mineralogy ,Pyroxene ,010502 geochemistry & geophysics ,01 natural sciences ,Diamond anvil cell ,Mantle (geology) ,Geochemistry and Petrology ,visual_art ,Transition zone ,Slab ,visual_art.visual_art_medium ,General Materials Science ,Eclogite ,0105 earth and related environmental sciences - Abstract
Diopside ($$CaMgSi_{2}O_{6}$$), the Ca- and Mg-rich clinopyroxene is an important mineral in the Earth’s upper mantle and subducted lithospheric plate. Here, we report the results of high-pressure single-crystal X-ray diffraction experiments conducted on a natural aluminous iron-bearing diopside and a natural, nearly end-member diopside, up to 50 GPa in diamond anvil cell. Density functional theory calculation results on end-member diopside are also reported. Unit cell parameters a, b, c, $$\beta$$, V, as well as bond lengths of diopside are reported and compared with other clinopyroxenes. Bulk modulus and its pressure derivative of the two diopside samples are determined using third-order Birch–Murnaghan equation of state. The density of the two diopside samples is calculated under cold subducting slab conditions and is compared with the seismic models. Along the cold slab geotherm, aluminous iron-bearing diopside has higher density than end-member diopside. In the upper mantle, eclogite with aluminous iron-bearing diopside is denser than eclogite with end-member diopside, and, therefore, provides larger slab pulling force. At the bottom of the transition zone and the top of the lower mantle, eclogite with aluminous iron-bearing diopside, though higher in density than the end-member diopside, is still less dense than the surrounding mantle and could contribute to the slab stagnation.
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- 2019
13. Lattice instability, anharmonicity and Raman spectra of BaO under high pressure: A first principles study
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K. Lavanya, N. Yedukondalu, S.C. Rakesh Roshan, Shweta D. Dabhi, Suresh Sripada, M. Sainath, Lars Ehm, and John B. Parise
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Condensed Matter - Materials Science ,Materials Science (cond-mat.mtrl-sci) ,FOS: Physical sciences ,General Materials Science ,General Chemistry ,Condensed Matter Physics - Abstract
Alkaline-earth metal oxides, in particular MgO and CaO dominate Earths lower mantle, therefore, exploring high pressure behavior of this class of compounds is of significant geophysical research interest. Among all these compounds, BaO exhibits rich polymorphism in the pressure range of 0-1.5 Mbar. Static enthalpy calculations revealed that BaO undergoes a pressure induced structural phase transition from NaCl-type (B1) $\rightarrow$ NiAs-type (B8) $\rightarrow$ distorted CsCl-type (d-B2) $\rightarrow$ CsCl-type (B2) at 5.1, 19.5, 120 GPa respectively. B1 $\rightarrow$ B8 $\&$ B8 $\rightarrow$ d-B2 transitions are found to be first order in nature whereas d-B2$\rightarrow$ B2 is a second order or weak first order phase transition. Interestingly, d-B2 phase shows stability over a wide pressure range, $\sim$19.5-113 GPa. Mechanical and dynamical stabilities of ambient and high pressure phases are demonstrated through computed elastic constants and phonon dispersion curves, respectively. Under high pressure, significant phonon softening and soft phonon mode along M-direction are observed for B8, d-B2 and B2 phases, respectively. Pressure dependent Raman spectra suggest a phase transition from d-B2 to Raman inactive phase under pressure. Overall, the present study provides a comprehensive understanding of underlying mechanisms behind pressure-induced structural phase transitions in BaO.
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- 2022
14. Seeking the most powerful and practical real-world sorbents for gaseous benzene as a representative volatile organic compound based on performance metrics
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Jan E. Szulejko, Ki-Hyun Kim, and John B. Parise
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chemistry.chemical_classification ,Sorbent ,business.industry ,Filtration and Separation ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Analytical Chemistry ,chemistry.chemical_compound ,020401 chemical engineering ,chemistry ,medicine ,Environmental science ,Volatile organic compound ,0204 chemical engineering ,0210 nano-technology ,Process engineering ,business ,Benzene ,Space velocity ,Activated carbon ,medicine.drug - Abstract
To assess the best sorbents available in real-world treatment of airborne volatile organic compounds (VOCs), we explored four sorbent performance metrics (10% breakthrough volume, space velocity, regeneration cycles, and cost) against benzene, a representative VOC, using well-known sorbents in the partial pressure (Pbenzene) range 0.01 – 1 Pa. Accordingly, some common materials (e.g., activated carbons) outperformed novel materials like MOFs. The performance of MOFs was often exaggerated as data were generally collected under unrealistic Pbenzene (e.g., >5,000 Pa). The use of metrics appropriate to real-world conditions is thus critical for selecting sorbents.
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- 2019
15. Fundamental study of furfuryl alcohol dehydration reaction over molybdenum oxide catalyst
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Nusnin Akter, Carmenn Ooi, J. Anibal Boscoboinik, Alwin James, Xiaojun Chan, Patrick Yang, John B. Parise, and Taejin Kim
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010405 organic chemistry ,Process Chemistry and Technology ,010402 general chemistry ,Photochemistry ,01 natural sciences ,Catalysis ,0104 chemical sciences ,Furfuryl alcohol ,chemistry.chemical_compound ,symbols.namesake ,X-ray photoelectron spectroscopy ,Dehydration reaction ,chemistry ,Oxidation state ,symbols ,Physical and Theoretical Chemistry ,Elongation ,Selectivity ,Raman spectroscopy - Abstract
The conversion of furfuryl alcohol (FA) and selectivity towards dimers (C9-C10) and trimers (C14-C15) were investigated over molybdenum oxide (MoO3) catalyst. It was observed that FA conversion increased as an increase of reaction time. However, longer reaction time tended to limit the selectivity to dimers and trimers. Characterization data obtained from XRD, Raman, and XPS showed that after the reaction the terminal Mo O bond was elongated and the oxidation state was changed from Mo6+ to Mo5+. This was likely caused by the delocalization of extra electron to the Mo center during the activation of FA on MoO3 surface, instead of the formation of oxygen vacancy. After a proper regeneration process, the structure distortion caused by the elongation of Mo O bond was fully restored, however, the oxidation state were only restored to Mo5+/6+. Recyclability test using regenerated MoO3 indicates Mo5+/6+ can be as active as Mo6+.
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- 2019
16. XRD-DSC: a screening tool for identifying effective MOFs for selective gas sorption from humid gas streams
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William R. Woerner, David M. Connors, Debasis Banerjee, Xianyin Chen, John B. Parise, Anna M. Plonka, and Nancy S. Goroff
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Radiation ,Materials science ,Enthalpy ,Sorption ,02 engineering and technology ,Microporous material ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Differential scanning calorimetry ,Adsorption ,chemistry ,Chemical engineering ,Imidazolate ,General Materials Science ,Metal-organic framework ,Relative humidity ,0210 nano-technology ,Instrumentation - Abstract
A commercially available combined X-ray diffraction – differential scanning calorimetry (XRD-DSC) stage was adapted for studies of gas loading in microporous materials, including metal organic frameworks (MOFs). Insertion of a custom-built humid atmosphere swing chamber (HASC) between a humidity generator and the XRD-DSC stage facilitates both humid atmosphere and vacuum swing gas loading. The HASC is necessary to buffer between the humidity generator and the XRD-DSC stage, allowing the gas mixture to homogenize prior to sample exposure, so that both humid atmosphere and vacuum swings could be performed. The changes in XRD can be used to follow structural changes, including collapse, which is indicative of a lack of microporosity upon activation, and the flexibity of frameworks upon gas sorption–desorption cycles. Measurements of the area under the DSC curve allows for calculation of the isosteric heat of adsorption (Qst; kJ molGAS−1). Vacuum-atmosphere swing experiments performed at different pressure steps allow for the reconstruction of the enthalpy of gas adsorption before and after a phase transition. These modes of operation are illustrated in three case studies from a program of exploratory MOF synthesis used to discover novel materials for selective gas sorption from humid gas streams: (1) gas binding in Stony Brook metal organic framework-1, (2) zeolitic imidazolate framework-7 response to variable pressure vacuum-atmosphere swing, and (3) high throughput evaluation of the selectivity of novel MOFs synthesized from customized linkers.
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- 2019
17. Highly active subnanometer Rh clusters derived from Rh-doped SrTiO3 for CO2 reduction
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Qiyuan Wu, Binhang Yan, Janis Timoshenko, Dong Su, Anatoly I. Frenkel, Alexander Orlov, Jiajie Cen, Eric A. Stach, Jingguang G. Chen, Xianyin Chen, and John B. Parise
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Materials science ,Hydrogen ,Process Chemistry and Technology ,Oxide ,chemistry.chemical_element ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,7. Clean energy ,Chemical reaction ,Catalysis ,Dissociation (chemistry) ,0104 chemical sciences ,X-ray absorption fine structure ,chemistry.chemical_compound ,chemistry ,Physical chemistry ,0210 nano-technology ,Selectivity ,Spectroscopy ,General Environmental Science - Abstract
Sub-nanometer Rh clusters derived from Rh-doped SrTiO3, demonstrated by in-situ X-ray Diffraction (XRD) and X-ray Absorption Fine Structure (XAFS) measurements, are applied as highly active catalysts for CO2 reduction. Compared to the supported Rh/SrTiO3, the catalyst synthesized by a doping-segregation method exhibits a higher space-time yield (STY) to CO with a selectivity of 95% for CO2 reduction by hydrogen; it also shows a higher activity with a larger turnover frequency (TOF) for CO2 reduction by ethane. According to the in-situ diffuse reflectance infrared Fourier transformed spectroscopy (DRIFTS) experiments, the higher CO selectivity for CO2 hydrogenation is attributed to the lower CO binding strength resulted by the strong interactions (e.g., charge transfer) between Rh atoms and the oxide support with surface defects. The superior activity is suggested to be originated from the cooperative effect between the highly dispersed sub-nanometer Rh clusters for efficient dissociation of H2/C2H6 and the reconstructed SrTiO3 with oxygen vacancies for preferential adsorption/activation of CO2. The doping-segregation method provides a unique opportunity to tune the size of active metal clusters and the physicochemical properties of the oxide support, offering the potential for applications in a variety of chemical reactions.
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- 2018
18. Raman and Near-Infrared Spectroscopy of Candidate X-Ray Amorphous Phases in Martian Rocks and Soils: Implications for Mars 2020 and ExoMars 2020 Data
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Jason Gregerson, Deanne Rogers, Lars Ehm, Elizabeth Sklute, and John B. Parise
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- 2020
19. Making tissintite: Mimicking meteorites in the multi-anvil
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Tristan Catalano, John B. Parise, M. Darby Dyar, Melinda J. Rucks, Steven J. Jaret, Matthew L. Whitaker, and Timothy D. Glotch
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Geophysics ,010504 meteorology & atmospheric sciences ,Meteorite ,Geochemistry and Petrology ,High pressure ,Shock (circulatory) ,medicine ,medicine.symptom ,010502 geochemistry & geophysics ,01 natural sciences ,Geology ,0105 earth and related environmental sciences ,Astrobiology - Published
- 2018
20. CO3+1 network formation in ultra-high pressure carbonate liquids
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Paul A. Bingham, Richard A. Brooker, Mark Wilson, Yoshio Kono, Martin Wilding, John B. Parise, and James W E Drewitt
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Buoyancy ,Materials science ,Ionic bonding ,lcsh:Medicine ,02 engineering and technology ,engineering.material ,010502 geochemistry & geophysics ,01 natural sciences ,petrology ,Carbon cycle ,chemistry.chemical_compound ,Viscosity ,Phase (matter) ,Transition zone ,lcsh:Science ,structure of solids and liquids ,0105 earth and related environmental sciences ,Multidisciplinary ,lcsh:R ,021001 nanoscience & nanotechnology ,computational chemistry ,Silicate ,chemistry ,Chemical physics ,engineering ,Carbonate ,lcsh:Q ,0210 nano-technology - Abstract
Carbonate liquids are an important class of molten salts, not just for industrial applications, but also in geological processes. Carbonates are generally expected to be simple liquids, in terms of ionic interactions between the molecular carbonate anions and metal cations, and therefore relatively structureless compared to more “polymerized” silicate melts. But there is increasing evidence from phase relations, metal solubility, glass spectroscopy and simulations to suggest the emergence of carbonate “networks” at length scales longer than the component molecular anions. The stability of these emergent structures are known to be sensitive to temperature, but are also predicted to be favoured by pressure. This is important as a recent study suggests that subducted surface carbonate may melt near the Earth’s transition zone (~44 km), representing a barrier to the deep carbon cycle depending on the buoyancy and viscosity of these liquids. In this study we demonstrate a major advance in our understanding of carbonate liquids by combining simulations and high pressure measurements on a carbonate glass, (K2CO3-MgCO3) to pressures in excess of 40 GPa, far higher than any previous in situ study. We show the clear formation of extended low-dimensional carbonate networks of close CO32− pairs and the emergence of a “three plus one” local coordination environment, producing an unexpected increase in viscosity with pressure. Although carbonate melts may still be buoyant in the lower mantle, an increased viscosity by at least three orders of magnitude will restrict the upward mobility, possibly resulting in entrainment by the down-going slab.
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- 2019
21. Growth of Nanoparticles with Desired Catalytic Functions by Controlled Doping-Segregation of Metal in Oxide
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Alexander Orlov, Dmitri N. Zakharov, Qiyuan Wu, Xianyin Chen, John B. Parise, Jiajie Cen, Eric A. Stach, Janis Timoshenko, Binhang Yan, Huolin L. Xin, Anatoly I. Frenkel, Jingguang G. Chen, and Siyu Yao
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Materials science ,General Chemical Engineering ,Doping ,Oxide ,Nanoparticle ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Nanomaterial-based catalyst ,0104 chemical sciences ,Catalysis ,Metal ,chemistry.chemical_compound ,Chemical engineering ,chemistry ,visual_art ,Materials Chemistry ,visual_art.visual_art_medium ,0210 nano-technology ,Metal nanoparticles - Abstract
The size and morphology of metal nanoparticles (NPs) often play a critical role in defining the catalytic performance of supported metal nanocatalysts. However, common synthetic methods struggle to produce metal NPs of appropriate size and morphological control. Thus, facile synthetic methods that offer controlled catalytic functions are highly desired. Here we have identified a new pathway to synthesize supported Rh nanocatalysts with finely tuned spatial dimensions and controlled morphology using a doping-segregation method. We have analyzed their structure evolutions during both the segregation process and catalytic reaction using a variety of in situ spectroscopic and microscopic techniques. A correlation between the catalytic functional sites and activity in CO2 hydrogenation over supported Rh nanocatalysts is then established. This study demonstrates a facile strategy to design and synthesize nanocatalysts with desired catalytic functions.
- Published
- 2018
22. Unexpected visible light driven photocatalytic activity without cocatalysts and sacrificial reagents from a (GaN)1–x(ZnO)x solid solution synthesized at high pressure over the entire composition range
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William R. Woerner, Alexandra Sinclair, John B. Parise, Alwin James, Robert M. Palomino, Qiyuan Wu, Alexander Orlov, and H. A. Naveen Dharmagunawardhane
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Range (particle radiation) ,Materials science ,Hydrogen ,Band gap ,General Chemical Engineering ,Analytical chemistry ,chemistry.chemical_element ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry ,Reagent ,Phase (matter) ,Photocatalysis ,0210 nano-technology ,Solid solution ,Visible spectrum - Abstract
Optical and photocatalytic properties were determined for the solid solution series (GaN)1–x(ZnO)x synthesized at high pressure over the entire compositional range (x = 0.07 to 0.9). We report for the first time photocatalytic H2 evolution activity from water for (GaN)1–x(ZnO)x without cocatalysts, pH modifiers and sacrificial reagents. Syntheses were carried out by reacting GaN and ZnO in appropriate amounts at temperatures ranging from 1150 to 1200 °C, and at a pressure of 1 GPa. ZnGa2O4 was observed as a second phase, with the amount decreasing from 12.8 wt% at x = 0.07 to ∼0.5 wt% at x = 0.9. The smallest band gap of 2.65 eV and the largest average photocatalytic H2 evolution rate of 2.31 μmol h−1 were observed at x = 0.51. Samples with x = 0.07, 0.24 and 0.76 have band gaps of 2.89 eV, 2.78 eV and 2.83 eV, and average hydrogen evolution rates of 1.8 μmol h−1, 0.55 μmol h−1 and 0.48 μmol h−1, respectively. The sample with x = 0.9 has a band gap of 2.82 eV, but did not evolve hydrogen. An extended photocatalytic test showed considerable reduction of activity over 20 hours.
- Published
- 2018
23. Effects of copper loading on NH3-SCR and NO oxidation over Cu impregnated CHA zeolite
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Nusnin Akter, Taejin Kim, Xianyin Chen, John B. Parise, and Jorge Anibal Boscoboinik
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General Chemical Engineering ,Inorganic chemistry ,chemistry.chemical_element ,Selective catalytic reduction ,02 engineering and technology ,General Chemistry ,Activation energy ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Copper ,Redox ,0104 chemical sciences ,Catalysis ,chemistry ,0210 nano-technology ,Zeolite ,Selectivity ,Incipient wetness impregnation - Abstract
Cu/CHA catalysts with various Cu loadings (0.5 wt%–6.0 wt%) were synthesized via incipient wetness impregnation. The catalysts were applied to the selective catalytic reduction (SCR) of NO with NH3 and NO oxidation reaction. XRD and N2 adsorption-desorption data showed that CHA structure was maintained with the incorporation of Cu, while specific surface areas decreased with increasing Cu loading. At intermediate Cu loading, 4 wt%, the highest NH3-SCR activity was observed with ∼98% N2 selectivity from 150 °C to 300 °C. Small amounts of water, 2%, slightly increased NO conversion in addition to the remarkable N2O and NO2 reduction at high temperature. Water effects are attributed to the improved Cu ion reducibility and mobility. NO oxidation results provided no relation between NO2 formation and SCR activity. Physicochemical properties, NO conversion, N2 selectivity, and activation energy data showed that impregnated samples’ molecular structure and catalytic activity are comparable to the conventional ion-exchanged (IE) samples’ ones.
- Published
- 2017
24. Cluster mediated conversion of amorphous Al(OH)3 to γ-AlOOH
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Am. M. Abeykoon, U. Bednarksi, R. Garrard, Karena W. Chapman, Jack Simonson, Michelle L. Beauvais, Brian L. Phillips, John B. Parise, Alicia Baccarella, and S. Fischer
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Coalescence (physics) ,Photoluminescence ,Materials science ,Nucleation ,Pair distribution function ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,Nanocrystalline material ,Hydrothermal circulation ,0104 chemical sciences ,Electronic, Optical and Magnetic Materials ,Amorphous solid ,Inorganic Chemistry ,Crystallography ,Solid-state nuclear magnetic resonance ,Materials Chemistry ,Ceramics and Composites ,Physical and Theoretical Chemistry ,0210 nano-technology - Abstract
We report a synthetic pathway by which amorphous Al(OH)3 is converted to γ-AlOOH through hydrothermal reaction in the presence of water at temperature T = 473 K. X-ray pair distribution function measurements reveal that the initially amorphous Al(OH)3 possesses a locally γ-Al(OH)3-like structure, while nanocrystalline γ-AlOOH precipitates within 1 h of continuous hydrothermal exposure. Solid state nuclear magnetic resonance measurements show that resonant features associated with four- and five-member Al clusters persist through 20 min of hydrothermal treatment, and ultraviolet (UV) spectra mark the onset of UV-induced photoluminescent features characteristic to γ-AlOOH with 10 min of exposure, indicating a coexistence region of γ-Al(OH)3-like and γ-AlOOH-like amorphous species. Powder x-ray diffraction measurements of desiccated powders reveal that the conversion process takes place in distinct, power law-defined stages with initial γ-AlOOH nucleation occurring within the first 20 min, followed by a ~ 1 h period of rapid grain coarsening and the subsequent onset of Lifshitz-Slyozov-Wagner-like coalescence.
- Published
- 2021
25. Effect of niobium oxide phase on the furfuryl alcohol dehydration
- Author
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Taejin Kim, Xianyin Chen, John B. Parise, Tiancheng Pu, Alwin James, Jaeha Lee, Xiaojun Chan, and Do Heui Kim
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Process Chemistry and Technology ,Condensation ,Inorganic chemistry ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,medicine.disease ,01 natural sciences ,Catalysis ,0104 chemical sciences ,Furfuryl alcohol ,chemistry.chemical_compound ,symbols.namesake ,chemistry ,Phase (matter) ,medicine ,symbols ,Niobium oxide ,Dehydration ,0210 nano-technology ,Selectivity ,Raman spectroscopy - Abstract
Different structural phases (e.g., TT, T, and H) of niobium oxide were synthesized, characterized by XRD and Raman, and utilized for the furfuryl alcohol dehydration and condensation under mild conditions (100 °C and ambient pressure). Furfuryl alcohol conversion was dependent on reaction time and niobium oxide phase. Niobic acid and T/H phase transitional niobium oxide showed higher catalytic activity in comparison to a single crystalline phase niobium oxide. While T/H phase transitional niobium oxide showed higher conversion than that of niobic acid and TT phase niobium oxide, higher C 9 -C 15 products' selectivity (> 60%) was obtained with the latter catalysts.
- Published
- 2017
26. Local structural variation with oxygen fugacity in Fe2SiO4+ fayalitic iron silicate melts
- Author
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J. K. R. Weber, O. L. G. Alderman, Jacqueline A. Johnson, S. Sendelbach, Lawrie Skinner, Martin Wilding, Charles E. Johnson, Steve M. Heald, Anthony Tamalonis, Lena Lazareva, Chris J. Benmore, Hien-Yoong Hah, and John B. Parise
- Subjects
Chemistry ,Analytical chemistry ,Context (language use) ,010502 geochemistry & geophysics ,01 natural sciences ,XANES ,Aerodynamic levitation ,Bond length ,Geochemistry and Petrology ,Mineral redox buffer ,Oxidation state ,0103 physical sciences ,X-ray crystallography ,010306 general physics ,Spectroscopy ,0105 earth and related environmental sciences - Abstract
The structure of molten Fe2SiO4+x has been studied using both high-energy X-ray diffraction and Fe K-edge X-ray absorption near-edge structure (XANES) spectroscopy, combined with aerodynamic levitation and laser beam heating. A wide range of Fe3+ contents were accessed by varying the levitation and atmospheric gas composition. Diffraction measurements were made in the temperature (T) and oxygen partial pressure ranges 1624(21) < T < 2183(94) K (uncertainties in parentheses) and -5.6(3) < DFMQ < +2.8(5) log units (relative to the Fayalite-Magnetite-Quartz buffer). Iron K-edge XANES measurements covered the ranges 1557(33) < T < 1994(36) K and -2.1(3) < DFMQ < +4.4(3) log units. Fe3+ contents, x = Fe3+/RFe, estimated directly from the pre-edge peaks of the XANES spectra varied between 0.15(1) and 0.40(2). While these agree in some cases with semi-empirical models, notable discrepancies are discussed in the context of the redox kinetics and the limitations in both the models and in the calibrations used to derive oxidation state from XANES spectra. XANES pre-edge peak areas imply average Fe–O coordination numbers, nFeO, close to 5 for all Fe3+/RFe. Diffraction measurements yielded values of 4.4(2) < nFeO < 4.7(1). There is limited evidence for a linear trend nFeO(x) = 4.46(3) + 0.4(1)x. Asymmetric Fe–O bond length distributions peak at around 1.96A and have a shoulder arising from longer interatomic distances. Mean rFeO lie close to 2.06A , consistent with nFeO close to 5. These observations suggest that Fe2+ is less efficient at stabilizing tetrahedral Fe3+ compared to large monovalent alkali cations. Comparison of in-situ XANES estimates of Fe3+/RFe in the melts to those of the quenched solids obtained from XANES as well as Mo¨ssbauer spectroscopy indicate rapid oxidation during cooling, enabled by stirring of the melt by the levitation gas flow. As such, the oxidation state of hot komatiitic and other highly fluid melts may not be retained, even during rapid cooling, as it is for cooler basaltic and more silicic magmas.
- Published
- 2017
27. The structure of liquid alkali nitrates and nitrites
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Chris J. Benmore, Mark Wilson, Martin Wilding, Mauro C. C. Ribeiro, O. L. G. Alderman, Anthony Tamalonis, John B. Parise, and J. K. R. Weber
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Length scale ,Diffraction ,Scattering ,Ammonium nitrate ,Inorganic chemistry ,Analytical chemistry ,General Physics and Astronomy ,02 engineering and technology ,Radius ,021001 nanoscience & nanotechnology ,Alkali metal ,01 natural sciences ,ESTRUTURA ELETRÔNICA ,chemistry.chemical_compound ,Molecular dynamics ,chemistry ,0103 physical sciences ,Physical and Theoretical Chemistry ,Nitrite ,010306 general physics ,0210 nano-technology - Abstract
High energy X-ray diffraction has been combined with containerless techniques to determine the structure of a series of alkali and ammonium nitrate and nitrite liquids. The systems have been modelled using molecular dynamics simulation which allows for the flexibility of, and movement of charge within, the molecular anions. The model reproduces the experimentally-determined scattering functions in both the low- and high-Q regimes reflecting the inter- and intra-molecular length-scales. For ammonium nitrate the best fit to the diffraction data is obtained by assuming the NH4+ cation to have a radius closer to that for Cs+ rather than a smaller cation such as Rb+ as often previously assumed. The alkali nitrites show an emergent length scale, attributed to the nitrogen-nitrogen spatial correlations, that depends on both temperature and the identity of the alkali cation. The corresponding nitrates show a more subtle effect in the nitrogen-nitrogen correlations. As a result, the nature of this N-N length-scale appears different for the respective nitrites and nitrates.
- Published
- 2017
28. Thermal expansion in UO2 determined by high-energy X-ray diffraction
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Lawrie Skinner, Chris J. Benmore, Malcolm Guthrie, Mark A. Williamson, John B. Parise, O. L. G. Alderman, and J. K. R. Weber
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010302 applied physics ,Diffraction ,Nuclear and High Energy Physics ,Materials science ,Scattering ,Transition temperature ,Thermodynamics ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Upper and lower bounds ,Thermal expansion ,Condensed Matter::Materials Science ,Crystallography ,Materials Science(all) ,Nuclear Energy and Engineering ,0103 physical sciences ,X-ray crystallography ,Melting point ,General Materials Science ,Crystallite ,0210 nano-technology - Abstract
Here we present crystallographic analyses of high-energy X-ray diffraction data on polycrystalline UO2 up to the melting temperature. The Rietveld refinements of our X-ray data are in agreement with previous measurements, but are systematically located around the upper bound of their uncertainty, indicating a slightly steeper trend of thermal expansion compared to established values. This observation is consistent with recent first principles calculations.
- Published
- 2016
29. The structure and thermochemistry of K2CO3–MgCO3 glass
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Richard A. Brooker, Brian L. Phillips, John B. Parise, Paul A. Bingham, Mark Wilson, Geetu Sharma, Martin Wilding, and Alexandra Navrotsky
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Materials science ,Mechanical Engineering ,Sodium molybdate ,Potassium ,Analytical chemistry ,chemistry.chemical_element ,02 engineering and technology ,Calorimetry ,010502 geochemistry & geophysics ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,Standard enthalpy of formation ,Ion ,chemistry.chemical_compound ,chemistry ,Mechanics of Materials ,Thermochemistry ,Carbonate ,General Materials Science ,0210 nano-technology ,Ternary operation ,0105 earth and related environmental sciences - Abstract
© 2019 Materials Research Society. Carbonate glasses can be formed routinely in the system K2CO3-MgCO3. The enthalpy of formation for one such 0.55K2CO3-0.45MgCO3 glass was determined at 298 K to be 115.00 ± 1.21 kJ/mol by drop solution calorimetry in molten sodium molybdate (3Na2O·MoO3) at 975 K. The corresponding heat of formation from oxides at 298 K was -261.12 ± 3.02 kJ/mol. This ternary glass is shown to be slightly metastable with respect to binary crystalline components (K2CO3 and MgCO3) and may be further stabilized by entropy terms arising from cation disorder and carbonate group distortions. This high degree of disorder is confirmed by 13C MAS NMR measurement of the average chemical shift tensor values, which show asymmetry of the carbonate anion to be significantly larger than previously reported values. Molecular dynamics simulations show that the structure of this carbonate glass reflects the strong interaction between the oxygen atoms in distorted carbonate anions and potassium cations.
- Published
- 2019
30. Exploring the structure of glass-forming liquids using high energy X-ray diffraction, containerless methodology and molecular dynamics simulation
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John B. Parise, Mauro C.C. Ribiero, Martin Wilding, O. L. G. Alderman, Mark Wilson, Chris J. Benmore, Richard Weber, Anthony Tamalonis, and Paul F. McMillan
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Diffraction ,Materials science ,Scattering ,Nucleation ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials ,Crystal ,Condensed Matter::Soft Condensed Matter ,lcsh:Chemistry ,Molecular dynamics ,lcsh:QD1-999 ,Chemical physics ,Metastability ,X-ray crystallography ,Materials Chemistry ,Ceramics and Composites ,lcsh:TA401-492 ,lcsh:Materials of engineering and construction. Mechanics of materials ,Supercooling - Abstract
High energy X-ray diffraction can be combined with containerless techniques to provide information on the atomic arrangements in glass-forming liquids in stable and metastable regimes. The high incident energies provide bulk diffraction data to high values of scattering vector which enables significantly more robust analysis of the local and medium-range order that influences important physical properties such as viscosity and crystal nucleation.These combined techniques have been applied to a range of oxide liquids. In this contribution we illustrate addition of further dimensions to phase space by controlling the partial pressure of oxygen that permits the study liquids containing iron. The advantages of rapid data acquisition are also demonstrated in a study of tellurite glass-forming systems where a transition from ergodic to non-ergodic regimes in the deeply supercooled liquid is shown. Finally we demonstrate how descriptions of the liquid structure can be developed by combining HEXRD with molecular dynamics simulations. Keywords: X-ray diffraction, Containerless techniques, Liquid structure
- Published
- 2019
31. CO
- Author
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Martin, Wilding, Paul A, Bingham, Mark, Wilson, Yoshio, Kono, James W E, Drewitt, Richard A, Brooker, and John B, Parise
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Computational chemistry ,Structure of solids and liquids ,Article ,Petrology - Abstract
Carbonate liquids are an important class of molten salts, not just for industrial applications, but also in geological processes. Carbonates are generally expected to be simple liquids, in terms of ionic interactions between the molecular carbonate anions and metal cations, and therefore relatively structureless compared to more “polymerized” silicate melts. But there is increasing evidence from phase relations, metal solubility, glass spectroscopy and simulations to suggest the emergence of carbonate “networks” at length scales longer than the component molecular anions. The stability of these emergent structures are known to be sensitive to temperature, but are also predicted to be favoured by pressure. This is important as a recent study suggests that subducted surface carbonate may melt near the Earth’s transition zone (~44 km), representing a barrier to the deep carbon cycle depending on the buoyancy and viscosity of these liquids. In this study we demonstrate a major advance in our understanding of carbonate liquids by combining simulations and high pressure measurements on a carbonate glass, (K2CO3-MgCO3) to pressures in excess of 40 GPa, far higher than any previous in situ study. We show the clear formation of extended low-dimensional carbonate networks of close CO32− pairs and the emergence of a “three plus one” local coordination environment, producing an unexpected increase in viscosity with pressure. Although carbonate melts may still be buoyant in the lower mantle, an increased viscosity by at least three orders of magnitude will restrict the upward mobility, possibly resulting in entrainment by the down-going slab.
- Published
- 2019
32. Direct Structural Identification of Gas Induced Gate‐Opening Coupled with Commensurate Adsorption in a Microporous Metal–Organic Framework
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Debasis Banerjee, John B. Parise, Thomas J. Emge, Hui Wang, Jing Li, and Anna M. Plonka
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Chemistry ,Organic Chemistry ,Inorganic chemistry ,02 engineering and technology ,General Chemistry ,Microporous material ,Crystal structure ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Catalysis ,0104 chemical sciences ,chemistry.chemical_compound ,Differential scanning calorimetry ,Adsorption ,Chemical engineering ,Propane ,Molecule ,Metal-organic framework ,0210 nano-technology ,Single crystal - Abstract
Gate-opening is a unique and interesting phenomenon commonly observed in flexible porous frameworks, where the pore characteristics and/or crystal structures change in response to external stimuli such as adding or removing guest molecules. For gate-opening that is induced by gas adsorption, the pore-opening pressure often varies for different adsorbate molecules and, thus, can be applied to selectively separate a gas mixture. The detailed understanding of this phenomenon is of fundamental importance to the design of industrially applicable gas-selective sorbents, which remains under investigated due to the lack of direct structural evidence for such systems. We report a mechanistic study of gas-induced gate-opening process of a microporous metal-organic framework, [Mn(ina)2 ] (ina=isonicotinate) associated with commensurate adsorption, by a combination of several analytical techniques including single crystal X-ray diffraction, in situ powder X-ray diffraction coupled with differential scanning calorimetry (XRD-DSC), and gas adsorption-desorption methods. Our study reveals that the pronounced and reversible gate opening/closing phenomena observed in [Mn(ina)2 ] are coupled with a structural transition that involves rotation of the organic linker molecules as a result of interaction of the framework with adsorbed gas molecules including carbon dioxide and propane. The onset pressure to open the gate correlates with the extent of such interaction.
- Published
- 2016
33. Magnetic Hydrogels from Alkyne/Cobalt Carbonyl-Functionalized ABA Triblock Copolymers
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Kim Kisslinger, Laura C. Pavelka, Wendy L. Hom, Bingyin Jiang, Surita R. Bhatia, Robert B. Grubbs, Pengqing Yu, Xianyin Chen, and John B. Parise
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chemistry.chemical_classification ,Ethylene oxide ,Alkyne ,chemistry.chemical_element ,Chain transfer ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Biochemistry ,Catalysis ,0104 chemical sciences ,Styrene ,chemistry.chemical_compound ,Colloid and Surface Chemistry ,chemistry ,Polymerization ,Self-healing hydrogels ,Polymer chemistry ,Copolymer ,0210 nano-technology ,Cobalt - Abstract
A series of alkyne-functionalized poly(4-(phenylethynyl)styrene)-block-poly(ethylene oxide)-block-poly(4-(phenylethynyl)styrene) (PPES-b-PEO-b-PPES) ABA triblock copolymers was synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization. PESn[Co2(CO)6]x-EO800-PESn[Co2(CO)6]x ABA triblock copolymer/cobalt adducts (10-67 wt % PEO) were subsequently prepared by reaction of the alkyne-functionalized PPES block with Co2(CO)8 and their phase behavior was studied by TEM. Heating triblock copolymer/cobalt carbonyl adducts at 120 °C led to cross-linking of the PPES/Co domains and the formation of magnetic cobalt nanoparticles within the PPES/Co domains. Magnetic hydrogels could be prepared by swelling the PEO domains of the cross-linked materials with water. Swelling tests, rheological studies and actuation tests demonstrated that the water capacity and modulus of the hydrogels were dependent upon the composition of the block copolymer precursors.
- Published
- 2016
34. Light Hydrocarbon Adsorption Mechanisms in Two Calcium-Based Microporous Metal Organic Frameworks
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Debasis Banerjee, Rajamani Krishna, William R. Woerner, Hui Wang, Xianyin Chen, John B. Parise, Jing Li, Anna M. Plonka, Yu Han, and Xinglong Dong
- Subjects
chemistry.chemical_classification ,Chemistry ,General Chemical Engineering ,Inorganic chemistry ,02 engineering and technology ,General Chemistry ,Microporous material ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Adsorption ,Hydrocarbon ,Acetylene ,Materials Chemistry ,Molecule ,Metal-organic framework ,0210 nano-technology ,Protein crystallization ,Single crystal - Abstract
The adsorption mechanism of ethane, ethylene, and acetylene (C2Hn; n = 2, 4, 6) on two microporous metal organic frameworks (MOFs) is described here that is consistent with observations from single crystal and powder X-ray diffraction, calorimetric measurements, and gas adsorption isotherm measurements. Two calcium-based MOFs, designated as SBMOF-1 and SBMOF-2 (SB: Stony Brook), form three-dimensional frameworks with one-dimensional open channels. As determined from single crystal diffraction experiments, channel geometries of both SBMOF-1 and SBMOF-2 provide multiple adsorption sites for hydrocarbon molecules through C–H···π and C–H···O interactions, similarly to interactions in the molecular and protein crystals. Both materials selectively adsorb C2 hydrocarbon gases over methane as determined with IAST and breakthrough calculations as well as experimental breakthrough measurements, with C2H6/CH4 selectivity as high as 74 in SBMOF-1.
- Published
- 2016
35. Phase Behavior of Alkyne-Functionalized Styrenic Block Copolymer/Cobalt Carbonyl Adducts and in Situ Formation of Magnetic Nanoparticles by Thermolysis
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Tadanori Koga, Kim Kisslinger, Dmytro Nykypanchuk, Xianyin Chen, John B. Parise, Robert B. Grubbs, Bin Qian, Bingyin Jiang, and Maya K. Endoh
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chemistry.chemical_classification ,Materials science ,Polymers and Plastics ,Organic Chemistry ,Thermal decomposition ,Alkyne ,Chain transfer ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Styrene ,Inorganic Chemistry ,chemistry.chemical_compound ,chemistry ,Polymerization ,Phase (matter) ,Polymer chemistry ,Materials Chemistry ,Copolymer ,Lamellar structure ,0210 nano-technology - Abstract
A series of polystyrene-block-poly(4-(phenylethynyl)styrene) (PS-b-PPES) diblock copolymers with a range of compositions were prepared by reversible addition–fragmentation chain transfer (RAFT) polymerization. Block copolymer/cobalt carbonyl adducts (PSx-PPESy[Co2(CO)6]n) were subsequently prepared by reaction of Co2(CO)8 with the alkyne groups of the PPES block. Phase behavior of the block copolymer/cobalt carbonyl adducts (PSx-PPESy[Co2(CO)6]n, 8% ≤ wt % PS ≤ 68%) was studied by small-angle X-ray scattering and transmission electron microscopy (TEM). As the composition of PSx-PPESy[Co2(CO)6]n copolymers was shifted from PS as the majority block to PPESy[Co2(CO)6]n as the majority block, the morphology was observed to shift from lamellar with larger PS domains to cylindrical with PS as the minority component and then to spherical with PS as the minority component. These observations have been used to map out a partial phase diagram for PSx-PPESy[Co2(CO)6]n diblock copolymers. Heating of PSx-PPESy[Co2(CO)...
- Published
- 2016
36. Direct structural evidence of commensurate-to-incommensurate transition of hydrocarbon adsorption in a microporous metal organic framework
- Author
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William R. Woerner, John B. Parise, Thomas J. Emge, Jing Li, Qihan Gong, Haohan Wu, Anna M. Plonka, David H. Olson, Hui Wang, Jacek Jagiello, and Debasis Banerjee
- Subjects
Chemistry ,Inorganic chemistry ,02 engineering and technology ,General Chemistry ,Microporous material ,Crystal structure ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Condensed Matter::Soft Condensed Matter ,Condensed Matter::Materials Science ,Adsorption ,Differential scanning calorimetry ,Physisorption ,Chemical physics ,Molecule ,Metal-organic framework ,Physics::Chemical Physics ,0210 nano-technology ,Single crystal - Abstract
The efficiency of physisorption-based separation of gas-mixtures depends on the selectivity of adsorbent which is directly linked to size, shape, polarizability and other physical properties of adsorbed molecules. Commensurate adsorption is an interesting and important adsorption phenomenon, where the adsorbed amount, location, and orientation of an adsorbate are commensurate with the crystal symmetry of the adsorbent. Understanding this phenomenon is important and beneficial as it can provide vital information about adsorbate–adsorbent interaction and adsorption–desorption mechanism. So far, only sporadic examples of commensurate adsorption have been reported in porous materials such as zeolites and metal organic frameworks (MOFs). In this work we show for the first time direct structural evidence of commensurate-to-incommensurate transition of linear hydrocarbon molecules (C2–C7) in a microporous MOF, by employing a number of analytical techniques including single crystal X-ray diffraction (SCXRD), in situ powder X-ray diffraction coupled with differential scanning calorimetry (PXRD-DSC), gas adsorption and molecular simulations.
- Published
- 2016
37. Simultaneous in Situ X-ray Diffraction and Calorimetric Studies as a Tool To Evaluate Gas Adsorption in Microporous Materials
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William R. Woerner, Praveen K. Thallapally, Debasis Banerjee, Xianyin Chen, John B. Parise, and Anna M. Plonka
- Subjects
Flue gas ,Chemistry ,Mineralogy ,02 engineering and technology ,Microporous material ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,General Energy ,Adsorption ,Differential scanning calorimetry ,Chemical engineering ,X-ray crystallography ,Imidazole ,Physical and Theoretical Chemistry ,0210 nano-technology ,Zeolite ,Water vapor - Abstract
Combined application of in situ X-ray diffraction (XRD) and differential scanning calorimetry (DSC) is a novel technique for rapidly evaluating the suitability of microporous materials for postcombustion CO2 capture. Further, while many microporous materials show promise for CO2 capture, most are not evaluated in the presence of water vapor, a major component of postcombustion flue gas. As a demonstration of the versatility of XRD-DSC techniques, representatives of the classes of materials typically proposed for CO2 capture, zeolites, and metal–organic frameworks (MOFs) were studied: zeolite NaX, Ni-MOF-74 [Ni2(dobdc); dobdc = 2,5-dihydroxyterephthalate], ZIF-7 [ZIF: zeolitic imidazole framework, Zn(phim)2; phim: benzimidazole], and SBMOF-1 [Ca(sdb); sdb: 4,4′-sulfonyldibenzoate]. Although NaX and Ni-MOF-74 show very high affinity toward CO2 under idealized dry conditions, they are also very sensitive to the presence of water vapor and experience significant performance loss above 25% relative humidity (R...
- Published
- 2015
38. Iodine in Metal-Organic Frameworks at High Pressure
- Author
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Xiaojun Chan, Sanjit Ghose, Hui Zhong, Taejin Kim, Alexander F. Goncharov, Lars Ehm, Sergey S. Lobanov, John A. Daly, and John B. Parise
- Subjects
Absorption spectroscopy ,Inorganic chemistry ,chemistry.chemical_element ,Sorption ,02 engineering and technology ,Electronic structure ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Iodine ,01 natural sciences ,0104 chemical sciences ,Polyiodide ,chemistry.chemical_compound ,chemistry ,Polymerization ,Molecule ,Metal-organic framework ,Physical and Theoretical Chemistry ,0210 nano-technology - Abstract
Capture of highly volatile radioactive iodine is a promising application of metal-organic frameworks (MOFs), thanks to their high porosity with flexible chemical architecture. Specifically, strong charge-transfer binding of iodine to the framework enables efficient and selective iodine uptake as well as its long-term storage. As such, precise knowledge of the electronic structure of iodine is essential for a detailed modeling of the iodine sorption process, which will allow for rational design of iodophilic MOFs in the future. Here we probe the electronic structure of iodine in MOFs at variable iodine···framework interaction by Raman and optical absorption spectroscopy at high pressure ( P). The electronic structure of iodine in the straight channels of SBMOF-1 (Ca- sdb, sdb = 4,4'-sulfonyldibenzoate) is modified irreversibly at P3.4 GPa by charge transfer, marking a polymerization of iodine molecules into a 1D polyiodide chain. In contrast, iodine in the sinusoidal channels of SBMOF-3 (Cd- sdb) retains its molecular (I
- Published
- 2018
39. Iodine Adsorption in Metal Organic Frameworks in the Presence of Humidity
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Praveen K. Thallapally, Taejin Kim, Xiaojun Chan, John A. Daly, Debasis Banerjee, Sergey S. Lobanov, Xianyin Chen, John B. Parise, and Anna M. Plonka
- Subjects
Materials science ,Radioactive waste ,Sorption ,02 engineering and technology ,Microporous material ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Spent nuclear fuel ,0104 chemical sciences ,Adsorption ,Chemical engineering ,General Materials Science ,Metal-organic framework ,0210 nano-technology ,Volatility (chemistry) ,Water vapor - Abstract
Used nuclear fuel reprocessing represents a unique challenge when dealing with radionuclides such as isotopes of 85Kr and 129I2 due to their volatility and long half-life. Efficient capture of 129I2 ( t1/2 = 15.7 × 106 years) from the nuclear waste stream can help reduce the risk of releasing I2 radionuclide into the environment and/or potential incorporation into the human thyroid. Metal organic frameworks have the reported potential to be I2 adsorbents but the effect of water vapor, generally present in the reprocessing off-gas stream, is rarely taken into account. Moisture-stable porous metal organic frameworks that can selectively adsorb I2 in the presence of water vapor are thus of great interest. Herein, we report on the I2 adsorption capacity of two microporous metal organic frameworks at both dry and humid conditions. Single-crystal X-ray diffraction and Raman spectroscopy reveal distinct sorption sites of molecular I2 within the pores in proximity to the phenyl- and phenol-based linkers stabilized by the I···π and I···O interactions, which allow selective uptake of iodine.
- Published
- 2018
40. Structure and Liquid Fragility in Sodium Carbonate
- Author
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Anthony Tamalonis, Mauro C. C. Ribeiro, J. K. R. Weber, Martin Wilding, Chris J. Benmore, O. L. G. Alderman, Mark Wilson, and John B. Parise
- Subjects
SÓDIO ,Chemistry ,Charge separation ,Charge density ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Local structure ,Ion ,chemistry.chemical_compound ,Fragility ,Chemical physics ,0103 physical sciences ,Carbonate ,Physical and Theoretical Chemistry ,010306 general physics ,0210 nano-technology ,Sodium carbonate - Abstract
The relationship between local structure and dynamics is explored for molten sodium carbonate. A flexible fluctuating-charge model, which allows for changes in the shape and charge distribution of the carbonate molecular anion, is developed. The system shows the evolution of highly temperature-dependent complex low-dimensional structures which control the dynamics (and hence the liquid fragility). By varying the molecular anion charge distribution, the key interactions responsible for the formation of these structures can be identified and rationalized. An increase in the mean charge separation within the carbonate ions increases the connectivity of the emerging structures and leads to an increase in the system fragility.
- Published
- 2017
41. Exploring the Structure of High Temperature, Iron-bearing Liquids
- Author
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John B. Parise, Richard Weber, Lawrie Skinner, Martin Wilding, Lena Lazareva, Chris J. Benmore, Antony Tamalonis, and O. L. G. Alderman
- Subjects
Quenching ,Materials science ,business.industry ,Slag ,Advanced Photon Source ,Steelmaking ,Viscosity ,Crystallography ,Chemical physics ,visual_art ,Metastability ,Smelting ,visual_art.visual_art_medium ,business ,Supercooling - Abstract
This paper describes the direct measurements of the structure of iron-bearing liquids using a combination of containerless techniques and in-situ high energy x-ray diffraction.These capabilities provide data that is important to help model and optimize processes such as smelting, steel making, and controlling slag chemistry. A successful programme of liquid studies has been undertaken and the Advanced Photon Source using these combined techniques which include the provision of gas mixing and the control of pO2and the changing influence of mixed valance elements. It is possible to combine rapid image acquisition with quenching of liquids to obtain the full diffraction patterns of deeply supercooled liquids and the metastable supercooled liquid regime, where the liquid structures and viscosity change most dramatically, can also be explored.
- Published
- 2015
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42. Molten uranium dioxide structure and dynamics
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Lawrie Skinner, T.C. Wiencek, J. K. R. Weber, John B. Parise, A. Hebden, Chris J. Benmore, L. Leibowitz, Mark A. Williamson, O. L. G. Alderman, Malcolm Guthrie, and Anthony Tamalonis
- Subjects
Zirconium ,Multidisciplinary ,Nuclear fuel ,Chemistry ,Fission ,Uranium dioxide ,Metallurgy ,chemistry.chemical_element ,Pair distribution function ,Mineralogy ,Oxygen ,chemistry.chemical_compound ,Levitation ,Leakage (electronics) - Abstract
Uranium dioxide (UO 2 ) is the major nuclear fuel component of fission power reactors. A key concern during severe accidents is the melting and leakage of radioactive UO 2 as it corrodes through its zirconium cladding and steel containment. Yet, the very high temperatures (>3140 kelvin) and chemical reactivity of molten UO 2 have prevented structural studies. In this work, we combine laser heating, sample levitation, and synchrotron x-rays to obtain pair distribution function measurements of hot solid and molten UO 2 . The hot solid shows a substantial increase in oxygen disorder around the lambda transition (2670 K) but negligible U-O coordination change. On melting, the average U-O coordination drops from 8 to 6.7 ± 0.5. Molecular dynamics models refined to this structure predict higher U-U mobility than 8-coordinated melts.
- Published
- 2014
43. Unexpected visible light driven photocatalytic activity without cocatalysts and sacrificial reagents from a (GaN)
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H A Naveen, Dharmagunawardhane, Alwin, James, Qiyuan, Wu, William R, Woerner, Robert M, Palomino, Alexandra, Sinclair, Alexander, Orlov, and John B, Parise
- Abstract
Optical and photocatalytic properties were determined for the solid solution series (GaN)
- Published
- 2017
44. Photocatalytic hydrogen evolution using nanocrystalline gallium oxynitride spinel
- Author
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Xianyin Chen, John B. Parise, Quiyan Wu, Huafeng Huang, Alexander Orlov, H. A. Naveen Dharmagunawardhane, Peter G. Khalifah, and William R. Woerner
- Subjects
Valence (chemistry) ,Materials science ,Renewable Energy, Sustainability and the Environment ,Inorganic chemistry ,Spinel ,Analytical chemistry ,chemistry.chemical_element ,General Chemistry ,engineering.material ,medicine.disease_cause ,Nanocrystalline material ,chemistry ,Photocatalysis ,engineering ,medicine ,General Materials Science ,Irradiation ,Gallium ,Hydrate ,Ultraviolet - Abstract
Photocatalytic hydrogen evolution from water was observed over nanocrystalline gallium oxynitride spinel under simulated solar light irradiation (320 nm < λ < 800 nm). Up to 8 μmol h−1 of H2 was evolved without co-catalyst loading. The photocatalyst was synthesized by the ammonolysis of gallium nitrate hydrate (Ga(NO3)3·xH2O). Optical measurements indicate an indirect gap (Eg) in the visible region (Eg = 2.50 eV) which is ascribed to photoexcitations from the N 2p valence states. A direct gap has an onset at ultraviolet energies (Eg = 3.69 eV), which is ascribed to photoexcitations from lower energy O 2p valence states.
- Published
- 2014
45. Structural Chemistry of Akdalaite, Al10O14(OH)2, the Isostructural Aluminum Analogue of Ferrihydrite
- Author
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Brian L. Phillips, John B. Parise, Bingying Xia, William R. Woerner, Anna M. Plonka, Lars Ehm, and Jack Simonson
- Subjects
akdalaite ,Boehmite ,Materials science ,General Chemical Engineering ,Crystal structure ,010501 environmental sciences ,engineering.material ,010502 geochemistry & geophysics ,ferrihydrite ,01 natural sciences ,Inorganic Chemistry ,solution synthesis ,Ferrihydrite ,NMR spectroscopy ,lcsh:QD901-999 ,General Materials Science ,Isostructural ,0105 earth and related environmental sciences ,Nuclear magnetic resonance spectroscopy ,Condensed Matter Physics ,Nanocrystalline material ,X-ray diffraction ,Crystallography ,bond valence sums ,X-ray crystallography ,engineering ,lcsh:Crystallography ,Akdalaite - Abstract
As part of an effort to characterize clusters and intermediate phases likely to be encountered along solution reaction pathways that produce iron and aluminum oxide-hydroxides from Fe and Al precursors, the complete structure of Al10O14(OH)2 (akdalaite) was determined from a combination of single-crystal X-ray diffraction (SC-XRD) data collected at 100 K to define the Al and O positions, and solid-state nuclear magnetic resonance (NMR) and neutron powder diffraction (NPD) data collected at room temperature (~300 K) to precisely determine the nature of hydrogen in the structure. Two different synthesis routes produced different crystal morphologies. Using an aluminum oxyhydroxide floc made from mixing AlCl3 and 0.48 M NaOH, the product had uniform needle morphology, while using nanocrystalline boehmite (Vista Chemical Company Catapal D alumina) as the starting material produced hexagonal plates. Akdalaite crystallizes in the space group P63mc with lattice parameters of a = 5.6244(3) Å, and c = 8.8417(3) Å, (SC-XRD) and a = 5.57610(2) Å, and c = 8.77247(6) Å, (NPD). The crystal structure features Al13O40 Keggin clusters. The structural chemistry of akdalaite is nonideal but broadly conforms to that of ferrihydrite, the nanomineral with which it is isostructural.
- Published
- 2019
46. From 1D Chain to 3D Network: A New Family of Inorganic–Organic Hybrid Semiconductors MO3(L)x (M = Mo, W; L = Organic Linker) Built on Perovskite-like Structure Modules
- Author
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Jing Li, Xiao Zhang, Ahmad Safari, Suraj Joottu Thiagarajan, Mehdi Hejazi, Ronggui Yang, William R. Woerner, Simon J. Teat, John B. Parise, Wenqian Xu, Debasis Banerjee, Qihan Gong, and Thomas J. Emge
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business.industry ,Chemistry ,Nanotechnology ,General Chemistry ,Crystal structure ,Dielectric ,Biochemistry ,Catalysis ,Colloid and Surface Chemistry ,Thermal conductivity ,Semiconductor ,Chemical engineering ,Negative thermal expansion ,Molecule ,business ,Linker ,Perovskite (structure) - Abstract
MO3 (M = Mo, W) or VI-VI binary compounds are important semiconducting oxides that show great promise for a variety of applications. In an effort to tune and enhance their properties in a systematic manner we have applied a designing strategy to deliberately introduce organic linker molecules in these perovskite-like crystal lattices. This approach has led to a wealth of new hybrid structures built on one-dimensional (1D) and two-dimensional (2D) VI-VI modules. The hybrid semiconductors exhibit a number of greatly improved properties and new functionality, including broad band gap tunability, negative thermal expansion, largely reduced thermal conductivity, and significantly enhanced dielectric constant compared to their MO3 parent phases.
- Published
- 2013
47. Effect of Ferrihydrite Crystallite Size on Phosphate Adsorption Reactivity
- Author
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Xionghan Feng, Xiaoming Wang, Wei Li, John B. Parise, Richard Harrington, Fan Liu, and Donald L. Sparks
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Surface Properties ,Inorganic chemistry ,General Chemistry ,Phosphate ,Ferric Compounds ,Phosphates ,law.invention ,chemistry.chemical_compound ,Ferrihydrite ,Adsorption ,chemistry ,law ,Specific surface area ,Nanoparticles ,Environmental Chemistry ,Reactivity (chemistry) ,Particle size ,Crystallite ,Particle Size ,Crystallization ,Nuclear chemistry - Abstract
The influence of crystallite size on the adsorption reactivity of phosphate on 2-line to 6-line ferrihydrites was investigated by combining adsorption experiments, structure and surface analysis, and spectroscopic analysis. X-ray diffraction (XRD) and transmission electron microscopy (TEM) showed that the ferrihydrite samples possessed a similar fundamental structure with a crystallite size varying from 1.6 to 4.4 nm. N2 adsorption on freeze-dried samples revealed that the specific surface area (SSABET) decreased from 427 to 234 m(2) g(-1) with increasing crystallite size and micropore volume (Vmicro) from 0.137 to 0.079 cm(3) g(-1). Proton adsorption (QH) at pH 4.5 and 0.01 M KCl ranged from 0.73 to 0.55 mmol g(-1). Phosphate adsorption capacity at pH 4.5 and 0.01 M KCl for the ferrihydrites decreased from 1690 to 980 μmol g(-1) as crystallite size increased, while the adsorption density normalized to SSABET was similar. Phosphate adsorption on the ferrihydrites exhibited similar behavior with respect to both kinetics and the adsorption mechanism. The kinetics could be divided into three successive first-order stages: relatively fast adsorption, slow adsorption, and a very slow stage. With decreasing crystallite size, ferrihydrites exhibited increasing rate constants per mass for all stages. Analysis of OH(-) release and attenuated total reflectance infrared spectroscopy (ATR-IR) and differential pair distribution function (d-PDF) results indicated that initially phosphate preferentially bound to two Fe-OH2(1/2+) groups to form a binuclear bidentate surface complex without OH(-) release, with smaller size ferrihydrites exchanging more Fe-OH2(1/2+) per mass. Subsequently, phosphate exchanged with both Fe-OH2(1/2+) and Fe-OH(1/2-) with a constant amount of OH(-) released per phosphate adsorbed. Also in this stage binuclear bidentate surface complexes were formed with a P-Fe atomic pair distance of ~3.25 Å.
- Published
- 2013
48. Synthesis, structural characterization and high pressure phase transitions of monolithium hydronium sulfate
- Author
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Debasis Banerjee, Wenqian Xu, John B. Parise, Sun Jin Kim, and Anna M. Plonka
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Materials science ,Hydronium ,Space group ,chemistry.chemical_element ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials ,Ion ,Inorganic Chemistry ,chemistry.chemical_compound ,symbols.namesake ,Crystallography ,chemistry ,X-ray crystallography ,Materials Chemistry ,Ceramics and Composites ,symbols ,Lithium ,Physical and Theoretical Chemistry ,Sulfate ,Raman spectroscopy ,Single crystal - Abstract
A three dimensional lithium hydronium sulfate LiSO4·H3O [1], [space group Pna21 a=8.7785(12) A, b=9.1297(12) A, c=5.2799(7) A, V=423.16(10) A3] was synthesized via solvothermal methods using 1,5-naphthalenedisulfonic acid (1,5-NSA) as the source of sulfate ions. The structure of [1], determined by single crystal X-ray diffraction techniques, consists of corner sharing LiO4 and SO4 tetrahedra, forming an anionic 3-D open framework that is charge balanced by hydronium ions positioned within channels running along [001] and forming strong H-bonding with the framework oxygen atoms. Compound [1] undergoes two reversible phase transitions, involving reorientation of SO42− ions at pressures of approximately 2.5 and 5 GPa at room temperature, as evident from characteristic discontinuous frequency drops in the ν1 mode of the Raman spectra. Additionally, compound [1] forms dense β-lithium sulfate at 300 °C, as evident from temperature dependent powder XRD and combined reversible TGA-DSC experiments.
- Published
- 2013
49. Temperature dependent structure formation and photoluminescence studies of a series of magnesium-based coordination networks
- Author
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Anna M. Plonka, Sun Jin Kim, Debasis Banerjee, Paul J. Calderone, and John B. Parise
- Subjects
Photoluminescence ,Quenching (fluorescence) ,Structure formation ,Chemistry ,Magnesium ,Inorganic chemistry ,chemistry.chemical_element ,Network connectivity ,Inorganic Chemistry ,Solvent ,Crystallography ,Hydrolysis ,Materials Chemistry ,Molecule ,Physical and Theoretical Chemistry - Abstract
A series of three magnesium trimesate coordination networks was synthesized from identical reaction mixtures by varying synthetic temperature. Mg(HBTC)(DMF)2·[(CH3)2NH] (1; BTC = trimesate; space group P63/m, a = 16.596(4) A, c = 14.351(8) A) crystallizes at 65 °C, Mg3(BTC)(HCOO)3(DMF)3 (2; space group P ¯ 3, a = 13.928(2) A, c = 8.025(6) A) crystallizes at 100 °C, and Mg3(BTC)2(DMF)4 (3; space group P21/c, a = 17.490(4) A, b = 11.940(2) A, c = 18.460(4) A, β = 116.87(3)°) crystallizes at a temperature of 180 °C. Each network contains metal-coordinated solvent DMF molecules, but thermodynamics and solvent hydrolysis play major roles in structure formation. Compounds 1 and 2 are two-dimensional networks which incorporate hydrolysis byproducts. Compound 3 is a three-dimensional network and shows no inclusion of byproducts. The series follows the trend of increased network connectivity resulting from increased temperature. Each of the networks show a weak photoluminescence response, suggesting that coordinated solvent molecules and interlayer species play a role in quenching photoluminescence.
- Published
- 2013
50. Lanthanide metal-organic frameworks based on a thiophenedicarboxylate linker: Characterization and luminescence
- Author
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Quddus A. Nizami, John B. Parise, Paul J. Calderone, Debasis Banerjee, and Anna M. Plonka
- Subjects
Lanthanide ,Quenching (fluorescence) ,Chemistry ,Metal ions in aqueous solution ,Inorganic chemistry ,General Chemistry ,Condensed Matter Physics ,Solvent ,Crystallography ,Molecule ,General Materials Science ,Metal-organic framework ,Isostructural ,Luminescence - Abstract
Three topologically-related lanthanide thiophenedicarboxylate (TDC) metal-organic frameworks were synthesized using an identical metal:linker:solvet ratio. Nd(TDC)3(EtOH)3(H2O)·H2O (1; space group Cc, a = 24.035(2) A, b = 10.063(1) A, c = 18.998(1) A, β = 132.41(1)°) contains the same metal-TDC coordination modes as two other compounds which have the isostructural formula Ln(TDC)3(EtOH)3(H2O)·H2O; Ln = Tb (2; space group P ¯ 1, a = 12.807(9) A, b = 14.557(1) A, c = 19.128(1) A, α = 106.66(2)°, β = 105.62(2)°, γ = 93.691(2)°), Dy (3; space group P ¯ 1, a = 12.793(8) A, b = 14.682(1) A, c = 19.077(1) A, α = 107.12(1)°, β = 105.54(1)°, γ = 93.518(2)°). An equimolar solvent mixture of water and ethanol causes both types of solvent molecules coordinating to metal centers. The fluorescence spectra of compounds 2 and 3 show characteristic bands related to their respective metal ions, but Dy-based 3 is very weak compared to Tb-based 2, indicating coordinating solvent molecules may be quenching Dy fluorescence.
- Published
- 2013
Catalog
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