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Alderman OLG, Benmore CJ, Holland D, Weber JKR. Boron coordination change in barium borate melts and glasses and its contribution to configurational heat capacity, entropy, and fragility. J Chem Phys 2023; 158:2895231. [PMID: 37290074 DOI: 10.1063/5.0153282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 05/10/2023] [Indexed: 06/10/2023] Open
Abstract
High-energy x-ray diffraction from molten and glassy BaB2O4 and BaB4O7 has been performed using aerodynamic levitation and laser heating over a wide range of temperatures. Remarkably, even in the presence of a heavy metal modifier dominating x-ray scattering, it was possible to extract accurate values for the tetrahedral, sp3, boron fraction, N4, which declines with increasing temperature, using bond valence-based mapping from the measured mean B-O bond lengths while accounting for vibrational thermal expansion. These are used within a boron-coordination-change model to extract enthalpies, ΔH, and entropies, ΔS, of isomerization between sp2 and sp3 boron. The results for BaB4O7, ΔH = 22(3) kJ mol-1 boron, ΔS = 19(2) J mol-1 boron K-1, agree quantitatively with those found previously for Na2B4O7. Analytical expressions for N4(J, T) and associated configurational heat capacity, CPconf(J, T), and entropy, Sconf(J, T), contributions are extended to cover a wide composition range 0 ≤ J = BaO/B2O3 ≤ 3 using a model for ΔH(J) and ΔS(J) derived empirically for lithium borates. Maxima in the CPconf(J, Tg) and fragility index contributions are thereby predicted for J ≲ 1, higher than the maximum observed and predicted in N4(J, Tg) at J ≃ 0.6. We discuss the utility of the boron-coordination-change isomerization model in the context of borate liquids containing other modifiers and the prospect of neutron diffraction to aid in empirical determinations of modifier-dependent effects, illustrated by new neutron diffraction data on Ba11B4O7 glass, its well-known α-polymorph, and lesser-known δ-phase.
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Affiliation(s)
- O L G Alderman
- ISIS Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Campus, Didcot OX11 0QX, United Kingdom
| | - C J Benmore
- X-Ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - D Holland
- Department of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - J K R Weber
- X-Ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA
- Materials Development, Inc., Arlington Heights, Illinois 60004, USA
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Topper B, Möncke D, Youngman RE, Valvi C, Kamitsos EI, Varsamis CPE. Zinc borate glasses: properties, structure and modelling of the composition-dependence of borate speciation. Phys Chem Chem Phys 2023; 25:5967-5988. [PMID: 36752128 DOI: 10.1039/d2cp05517a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The short-range order of binary zinc borate glasses, xZnO-(1-x)B2O3, has been quantitatively described as a function of ZnO content over the entire glass forming range for the first time, to the best of our knowledge. Multiple spectroscopic techniques (11B NMR, Raman, infrared) reveal detailed structural information regarding borate speciation and network connectivity, and a new model for quantifying the molar fractions of short-range order units is proposed. A consistent thermal history dependence for the fraction of tetrahedral boron (N4) is well accounted for by the proposed model. The model predicts density within 0.1% of experimental values and N4 to within 1% of NMR values. The intermediate character of four-coordinated zinc in borate glasses of this series is evident by the far infrared profiles and the glass transition temperature behavior, which decreases non-monotonically with increasing ZnO content.
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Affiliation(s)
- Brian Topper
- Inamori School of Engineering at the New York State College of Ceramics, Alfred University, 1 Saxon Drive, Alfred, NY 14802, USA. .,Department of Physics & Astronomy and Center for High Technology Materials, University of New Mexico, Albuquerque, NM 87131, USA
| | - Doris Möncke
- Inamori School of Engineering at the New York State College of Ceramics, Alfred University, 1 Saxon Drive, Alfred, NY 14802, USA.
| | - Randall E Youngman
- Science and Technology Division, Corning Incorporated, Corning, New York 14831, USA
| | - Christina Valvi
- Applied Physics Laboratory, Faculty of Engineering, University of West Attica, 250 Thivon, 112 41 Egaleo, Attica, Greece.
| | - Efstratios I Kamitsos
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece
| | - Christos P E Varsamis
- Applied Physics Laboratory, Faculty of Engineering, University of West Attica, 250 Thivon, 112 41 Egaleo, Attica, Greece.
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Anomalous structure transition in undercooled melt regulates polymorphic selection in barium titanate crystallization. Commun Chem 2021; 4:27. [PMID: 36697544 PMCID: PMC9814643 DOI: 10.1038/s42004-021-00462-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 02/01/2021] [Indexed: 01/28/2023] Open
Abstract
The crystallization processes of titanates are central to the fabrication of optical and electrical crystals and glasses, but their rich polymorphism is not fully understood. Here, we show when and how polymorphic selection occurs during the crystallization of barium titanate (BaTiO3, BT) using in situ high energy synchrotron X-ray diffraction and ab initio molecular dynamic simulation. An anomalous structure transition is found in molten BT during cooling across the cubic-hexagonal transition temperature, which enables nucleation selection of BT by manipulating the undercooling: a cubic phase is preferred if nucleation is triggered at large undercooling, whereas a hexagonal phase is promoted at small undercooling. We further reveal that the nucleation selection between the cubic and the hexagonal phase is regulated by the intrinsic structure property of the melt, in particular, the degree of polymerization between Ti-O polyhedra. These findings provide an innovative perspective to link the polymorphic crystallization to the non-isomorphic structure transition of the melt beyond the conventional cognition of structural heredity.
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Examination of structure and optical properties of Ce 3+-doped strontium borate glass by regression analysis. Sci Rep 2021; 11:3811. [PMID: 33589692 PMCID: PMC7884713 DOI: 10.1038/s41598-021-83050-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 01/28/2021] [Indexed: 11/16/2022] Open
Abstract
Amorphous materials with non-periodic structures are commonly evaluated based on their chemical composition, which is not always the best parameter to evaluate physical properties, and an alternative parameter more suitable for performance evaluation must be considered. Herein, we quantified various structural and physical properties of Ce-doped strontium borate glasses and studied their correlations by principal component analysis. We found that the density-driven molar volume is suitable for the evaluation of structural data, while chemical composition is better for the evaluation of optical and luminescent data. Furthermore, the borate-rich glasses exhibited a stronger luminescence due to Ce3+, indicating a higher fraction of BO3/2 ring and larger cavity. Moreover, the internal quantum efficiency was found to originate from the local coordination states of the Ce3+ centres, independent of composition or molar volume. The comparison of numerical data of the matrix is useful not only for ensuring the homogenous doping of amorphous materials by activators, but also for determining the origin of physical properties.
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Möncke D, Ali S, Jonson B, Kamitsos EI. Anion polarizabilities in oxynitride glasses. Establishing a common optical basicity scale. Phys Chem Chem Phys 2020; 22:9543-9560. [PMID: 32319995 DOI: 10.1039/c9cp06930e] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Inspired by the work of John Duffy on optical basicity of oxyfluoride glasses, we apply here the concept of optical basicity to oxynitride systems. While in the original work of Duffy and Ingram the basicity of a medium could be probed by s2 ions like Pb2+, the low energy intrinsic absorption edge of nitride-containing systems does not allow the use of such probe ions. This study uses therefore experimental data on refractive index and density of alkaline earth and rare earth containing silicate oxynitride glasses, prepared by the authors or taken from the literature. In addition, literature reports on experimental or calculated refractive index, density and polarizability data are used to compare pure nitride systems, e.g. bulk or thin film materials that are either crystalline or glassy. We compare simple and complex nitride systems with their oxygen counterparts, by calculating their optical basicity using the chemical composition as well as the established relationship between optical basicity, Λ, and electronic polarizability in oxide systems. Our results on oxynitride systems are in good agreement with Duffy's previous work on oxyfluoride glasses and indicate that the optical basicity varies for the isoelectronic anions in nitrides, oxides and fluorides (N3-:O2-:F-) of a cation Mm+ as follows: Λ(MFm) = 1/2Λ(M2Om) = 1/3Λ(M3Nm). Using this relation for CaO, for which the optical basicity was set as unity by Duffy and Ingram, one has Λ(CaF2) = 0.50, Λ(CaO) = 1.00 and Λ(Ca3N2) = 1.50. The optical basicity of complex nitrides can therefore be calculated by the same method established for oxides using the equivalent fractions and the basicity of the constituent nitrides. The relationship between nitride polarizability αN and basicity Λ(nitride) was found to be linear, with Λ(nitride) = 0.39αN- 0.14 where αN is given in Å3.
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Affiliation(s)
- Doris Möncke
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece.
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A. Marques RV, Saturnino M, Martins F, Velasquez Cabrera CE, Pereira Bezerra Lima C, Fortini Veloso MA, Costa AL. Tritium Breeder Layer Evaluation of Fusion-Fission Hybrid System. FUSION SCIENCE AND TECHNOLOGY 2020. [DOI: 10.1080/15361055.2019.1704594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Renato Vinicius A. Marques
- Universidade Federal de Minas Gerais, Departamento de Engenharia Nuclear, Escola de Engenharia, UFMG Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais CEP 31270-901, Brazil
| | - Marcia Saturnino
- Universidade Federal de Minas Gerais, Departamento de Engenharia Nuclear, Escola de Engenharia, UFMG Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais CEP 31270-901, Brazil
| | - Felipe Martins
- Universidade Federal de Minas Gerais, Departamento de Engenharia Nuclear, Escola de Engenharia, UFMG Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais CEP 31270-901, Brazil
| | - Carlos Eduardo Velasquez Cabrera
- Universidade Federal de Minas Gerais, Departamento de Engenharia Nuclear, Escola de Engenharia, UFMG Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais CEP 31270-901, Brazil
| | - Claubia Pereira Bezerra Lima
- Universidade Federal de Minas Gerais, Departamento de Engenharia Nuclear, Escola de Engenharia, UFMG Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais CEP 31270-901, Brazil
| | - Maria Auxiliadora Fortini Veloso
- Universidade Federal de Minas Gerais, Departamento de Engenharia Nuclear, Escola de Engenharia, UFMG Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais CEP 31270-901, Brazil
| | - Antonella Lombardi Costa
- Universidade Federal de Minas Gerais, Departamento de Engenharia Nuclear, Escola de Engenharia, UFMG Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais CEP 31270-901, Brazil
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Alderman OLG, Benmore CJ, Feller S, Kamitsos EI, Simandiras ED, Liakos DG, Jesuit M, Boyd M, Packard M, Weber R. Short-Range Disorder in TeO 2 Melt and Glass. J Phys Chem Lett 2020; 11:427-431. [PMID: 31867975 DOI: 10.1021/acs.jpclett.9b03231] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
High-resolution X-ray pair distribution functions for molten and glassy TeO2 reveal coordination numbers nTeO ≈ 4. However, distinct from the known α-, β-, and γ-TeO2 polymorphs, there is considerable short-range disorder such that no clear cutoff distance between bonded and nonbonded interactions exists. We suggest that this is similar to disorder in δ-TeO2 and arises from a broad distribution of asymmetric Te-O-Te bridges, something that we observe becomes increasingly asymmetric with increasing liquid temperature. Such behavior is qualitatively consistent with existing interpretations of Raman scattering spectra, and equivalent to temperature-induced coordination number reduction, for sufficiently large cutoff radii. Therefore, TeO2 contains a distribution of local environments that are, furthermore, temperature dependent, making it distinct from the canonical single-oxide glass formers. Our results are in good agreement with high-level ab initio cluster calculations.
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Affiliation(s)
- O L G Alderman
- Materials Development, Inc. , Arlington Heights , Illinois 60004 , United States
| | - C J Benmore
- X-Ray Science Division, Advanced Photon Source , Argonne National Laboratory , Argonne , Illinois 60439 , United States
| | - S Feller
- Department of Physics , Coe College , Cedar Rapids , Iowa 52402 , United States
| | - E I Kamitsos
- National Hellenic Research Foundation , 48 Vassileos Constantinou Avenue , 11635 Athens , Greece
| | - E D Simandiras
- National Hellenic Research Foundation , 48 Vassileos Constantinou Avenue , 11635 Athens , Greece
| | - D G Liakos
- Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1 , 45470 Mülheim an der Ruhr , Germany
| | - M Jesuit
- Department of Physics , Coe College , Cedar Rapids , Iowa 52402 , United States
| | - M Boyd
- Department of Physics , Coe College , Cedar Rapids , Iowa 52402 , United States
| | - M Packard
- Department of Physics , Coe College , Cedar Rapids , Iowa 52402 , United States
| | - R Weber
- Materials Development, Inc. , Arlington Heights , Illinois 60004 , United States
- X-Ray Science Division, Advanced Photon Source , Argonne National Laboratory , Argonne , Illinois 60439 , United States
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Baroni A, Pacaud F, Salanne M, Micoulaut M, Delaye JM, Zeidler A, Salmon PS, Ferlat G. Many-body effects at the origin of structural transitions in B 2O 3. J Chem Phys 2019; 151:224508. [PMID: 31837684 DOI: 10.1063/1.5131763] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The structural properties of glassy diboron trioxide, g-B2O3, are investigated from ambient to high pressure conditions using two types of atomic force-field models that account for many-body effects. These models are parameterized by a dipole- and force-fitting procedure of reference datasets created via first-principles calculations on a series of configurations. The predictions of the models are tested against experimental data, where particular attention is paid to the structural transitions in g-B2O3 that involve changes to both the short- and medium-range order. The models outperform those previously devised, where improvement originates from the incorporation of two key physical ingredients, namely, (i) the polarizability of the oxide ion and (ii) the ability of an oxide ion to change both size and shape in response to its coordination environment. The results highlight the importance of many-body effects for accurately modeling this challenging system.
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Affiliation(s)
- Axelle Baroni
- Sorbonne Université, CNRS, PHENIX, F-75005 Paris, France
| | - Fabien Pacaud
- Sorbonne Université, CNRS, PHENIX, F-75005 Paris, France
| | | | | | - Jean-Marc Delaye
- CEA, DEN, Laboratoire d'Etude des Matériaux et Procédés Actifs, 30207 Bagnols-sur-Cèze, France
| | - Anita Zeidler
- Department of Physics, University of Bath, Bath BA2 7AY, United Kingdom
| | - Philip S Salmon
- Department of Physics, University of Bath, Bath BA2 7AY, United Kingdom
| | - Guillaume Ferlat
- Sorbonne Université, CNRS, MNHN, IRD, IMPMC, F-75005 Paris, France
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Lu WD, Wang D, Zhao Z, Song W, Li WC, Lu AH. Supported Boron Oxide Catalysts for Selective and Low-Temperature Oxidative Dehydrogenation of Propane. ACS Catal 2019. [DOI: 10.1021/acscatal.9b02284] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Wen-Duo Lu
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, P.R. China
| | - Dongqi Wang
- Center for Multi-Disciplinary Research, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Zhenchao Zhao
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, P.R. China
| | - Wei Song
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, P.R. China
| | - Wen-Cui Li
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, P.R. China
| | - An-Hui Lu
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, P.R. China
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Yu Y, Stevensson B, Edén M. Direct Experimental Evidence for Abundant BO 4-BO 4 Motifs in Borosilicate Glasses From Double-Quantum 11B NMR Spectroscopy. J Phys Chem Lett 2018; 9:6372-6376. [PMID: 30354174 DOI: 10.1021/acs.jpclett.8b02907] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
By using double-quantum-single-quantum correlation 11B nuclear magnetic resonance (NMR) experiments and atomistic molecular dynamics (MD) simulations, we resolve the long-standing controversy of whether directly interlinked BO4-BO4 groups exist in the technologically ubiquitous class of alkali/alkaline-earth based borosilicate (BS) glasses. Most structural models of Na2O-B2O3-SiO2 glasses assume the absence of B[4]-O-B[4] linkages, whereas they have been suggested to exist in Ca-bearing BS analogs. Our results demonstrate that while B[4]-O-B[4] linkages are disfavored relative to their B[3]-O-B[3]/B[4] counterparts, they are nevertheless abundant motifs in Na2O-B2O3-SiO2 glasses over a large composition space, while the B[4]-O-B[4] contents are indeed elevated in Na2O-CaO-B2O3-SiO2 glasses. We discuss the compositional and structural parameters that control the degree of B[4]-O-B[4] bonding.
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Affiliation(s)
- Yang Yu
- Physical Chemistry Division, Department of Materials and Environmental Chemistry , Stockholm University , SE-106 91 Stockholm , Sweden
| | - Baltzar Stevensson
- Physical Chemistry Division, Department of Materials and Environmental Chemistry , Stockholm University , SE-106 91 Stockholm , Sweden
| | - Mattias Edén
- Physical Chemistry Division, Department of Materials and Environmental Chemistry , Stockholm University , SE-106 91 Stockholm , Sweden
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Pacaud F, Delaye JM, Charpentier T, Cormier L, Salanne M. Structural study of Na2O–B2O3–SiO2 glasses from molecular simulations using a polarizable force field. J Chem Phys 2017; 147:161711. [DOI: 10.1063/1.4992799] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Yu Y, Stevensson B, Edén M. Medium-Range Structural Organization of Phosphorus-Bearing Borosilicate Glasses Revealed by Advanced Solid-State NMR Experiments and MD Simulations: Consequences of B/Si Substitutions. J Phys Chem B 2017; 121:9737-9752. [PMID: 28876931 DOI: 10.1021/acs.jpcb.7b06654] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The short and intermediate range structures of a large series of bioactive borophosphosilicate (BPS) glasses were probed by solid-state nuclear magnetic resonance (NMR) spectroscopy and atomistic molecular dynamics (MD) simulations. Two BPS glass series were designed by gradually substituting SiO2 by B2O3 in the respective phosphosilicate base compositions 24.1Na2O-23.3CaO-48.6SiO2-4.0P2O5 ("S49") and 24.6Na2O-26.7CaO-46.1SiO2-2.6P2O5 ("S46"), the latter constituting the "45S5 Bioglass" utilized for bone grafting applications. The BPS glass networks are built by interconnected SiO4, BO4, and BO3 moieties, whereas P exists mainly as orthophosphate anions, except for a minor network-associated portion involving P-O-Si and P-O-B[4] motifs, whose populations were estimated by heteronuclear 31P{11B} NMR experimentation. The high Na+/Ca2+ contents give fragmented glass networks with large amounts of nonbridging oxygen (NBO) anions. The MD-generated glass models reveal an increasing propensity for NBO accommodation among the network units according to BO4 < SiO4 < BO3 ≪ PO4. The BO4/BO3 intermixing was examined by double-quantum-single-quantum correlation 11B NMR experiments, which evidenced the presence of all three BO3-BO3, BO3-BO4, and BO4-BO4 connectivities, with B[3]-O-B[4] bridges dominating. Notwithstanding that B[4]-O-B[4] linkages are disfavored, both NMR spectroscopy and MD simulations established their presence in these modifier-rich BPS glasses, along with non-negligible B[4]-NBO contacts, at odds with the conventional structural view of borosilicate glasses. We discuss the relative propensities for intermixing of the Si/B/P network formers. Despite the absence of pronounced preferences for Si-O-Si bond formation, the glass models manifest subtle subnanometer-sized structural inhomogeneities, where SiO4 tetrahedra tend to self-associate into small chain/ring motifs embedded in BO3/BO4-dominated domains.
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Affiliation(s)
- Yang Yu
- Physical Chemistry Division, Department of Materials and Environmental Chemistry, Stockholm University , SE-106 91 Stockholm, Sweden
| | - Baltzar Stevensson
- Physical Chemistry Division, Department of Materials and Environmental Chemistry, Stockholm University , SE-106 91 Stockholm, Sweden
| | - Mattias Edén
- Physical Chemistry Division, Department of Materials and Environmental Chemistry, Stockholm University , SE-106 91 Stockholm, Sweden
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