1
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Kumar A, Craig VSJ, Robertson H, Page AJ, Webber GB, Wanless EJ, Mitchell VD, Andersson GG. Specific Ion Effects at the Vapor-Formamide Interface: A Reverse Hofmeister Series in Ion Concentration Depth Profiles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:12618-12626. [PMID: 37642667 DOI: 10.1021/acs.langmuir.3c01286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Employing neutral impact collision ion scattering spectroscopy (NICISS), we have directly measured the concentration depth profiles (CDPs) of various monovalent ions at the vapor-formamide interface. NICISS provides CDPs of individual ions by measuring the energy loss of neutral helium atoms backscattered from the solution interface. CDPs at the vapor-formamide interface of Cl-, Br-, I-, Na+, K+, and Cs+ are measured and compared to elucidate the interfacial specific ion trends. We report a reverse Hofmeister series in the presence of inorganic ions (anion and cation) at the vapor-formamide interface relative to the water-vapor interface, and the CDPs are found to be independent of the counterion for most ions studied. Thus, ions at the surface of formamide follow a "Hofmeister paradigm" where the counterion does not impact the ion series. These specific ion trends are complemented with surface tension and X-ray absorption near-edge structure (XANES) measurements on formamide electrolyte solutions.
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Affiliation(s)
- Anand Kumar
- Flinders Institute of Nanoscale Science and Technology, College of Science and Engineering, Flinders University, Adelaide, SA 5042, Australia
| | - Vincent S J Craig
- Department of Materials Physics, Research School of Physics, The Australian National University, Canberra, ACT 2601, Australia
| | - Hayden Robertson
- College of Science, Engineering, and Environment, University of Newcastle, Callaghan, NSW 2308, Australia
| | - Alister J Page
- College of Science, Engineering, and Environment, University of Newcastle, Callaghan, NSW 2308, Australia
| | - Grant B Webber
- College of Science, Engineering, and Environment, University of Newcastle, Callaghan, NSW 2308, Australia
| | - Erica J Wanless
- College of Science, Engineering, and Environment, University of Newcastle, Callaghan, NSW 2308, Australia
| | | | - Gunther G Andersson
- Flinders Institute of Nanoscale Science and Technology, College of Science and Engineering, Flinders University, Adelaide, SA 5042, Australia
- Flinders Microscopy and Microanalysis, College of Science and Engineering, Flinders University, Adelaide, SA 5042, Australia
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2
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Tran-Phu T, Chatti M, Leverett J, Nguyen TKA, Simondson D, Hoogeveen DA, Kiy A, Duong T, Johannessen B, Meilak J, Kluth P, Amal R, Simonov AN, Hocking RK, Daiyan R, Tricoli A. Understanding the Role of (W, Mo, Sb) Dopants in the Catalyst Evolution and Activity Enhancement of Co 3 O 4 during Water Electrolysis via In Situ Spectroelectrochemical Techniques. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023:e2208074. [PMID: 36932896 DOI: 10.1002/smll.202208074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 02/27/2023] [Indexed: 06/18/2023]
Abstract
Unlocking the potential of the hydrogen economy is dependent on achieving green hydrogen (H2 ) production at competitive costs. Engineering highly active and durable catalysts for both oxygen and hydrogen evolution reactions (OER and HER) from earth-abundant elements is key to decreasing costs of electrolysis, a carbon-free route for H2 production. Here, a scalable strategy to prepare doped cobalt oxide (Co3 O4 ) electrocatalysts with ultralow loading, disclosing the role of tungsten (W), molybdenum (Mo), and antimony (Sb) dopants in enhancing OER/HER activity in alkaline conditions, is reported. In situ Raman and X-ray absorption spectroscopies, and electrochemical measurements demonstrate that the dopants do not alter the reaction mechanisms but increase the bulk conductivity and density of redox active sites. As a result, the W-doped Co3 O4 electrode requires ≈390 and ≈560 mV overpotentials to reach ±10 and ±100 mA cm-2 for OER and HER, respectively, over long-term electrolysis. Furthermore, optimal Mo-doping leads to the highest OER and HER activities of 8524 and 634 A g-1 at overpotentials of 0.67 and 0.45 V, respectively. These novel insights provide directions for the effective engineering of Co3 O4 as a low-cost material for green hydrogen electrocatalysis at large scales.
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Affiliation(s)
- Thanh Tran-Phu
- Nanotechnology Research Laboratory, Research School of Chemistry, The Australian National University, Canberra, ACT, 2601, Australia
- Nanotechnology Research Laboratory, Faculty of Engineering, University of Sydney, Sydney, NSW, 2006, Australia
| | - Manjunath Chatti
- School of Chemistry, Monash University, Monash, Victoria, 3800, Australia
| | - Joshua Leverett
- Particles and Catalysis Research Laboratory, School of Chemical Engineering, The University of New South Wales, Sydney, NSW, 2052, Australia
| | - Thi Kim Anh Nguyen
- Nanotechnology Research Laboratory, Research School of Chemistry, The Australian National University, Canberra, ACT, 2601, Australia
- Nanotechnology Research Laboratory, Faculty of Engineering, University of Sydney, Sydney, NSW, 2006, Australia
| | - Darcy Simondson
- School of Chemistry, Monash University, Monash, Victoria, 3800, Australia
| | - Dijon A Hoogeveen
- School of Chemistry, Monash University, Monash, Victoria, 3800, Australia
| | - Alexander Kiy
- Department of Materials Physics, Research School of Physics, The Australian National University, Canberra, ACT, 2601, Australia
| | - The Duong
- School of Engineering, The Australian National University, Canberra, ACT, 2601, Australia
| | | | - Jaydon Meilak
- Department of Chemistry and Biotechnology, Swinburne University, Hawthorn, Victoria, 3166, Australia
| | - Patrick Kluth
- Department of Materials Physics, Research School of Physics, The Australian National University, Canberra, ACT, 2601, Australia
| | - Rose Amal
- Particles and Catalysis Research Laboratory, School of Chemical Engineering, The University of New South Wales, Sydney, NSW, 2052, Australia
| | - Alexandr N Simonov
- School of Chemistry, Monash University, Monash, Victoria, 3800, Australia
| | - Rosalie K Hocking
- Department of Chemistry and Biotechnology, Swinburne University, Hawthorn, Victoria, 3166, Australia
| | - Rahman Daiyan
- Particles and Catalysis Research Laboratory, School of Chemical Engineering, The University of New South Wales, Sydney, NSW, 2052, Australia
| | - Antonio Tricoli
- Nanotechnology Research Laboratory, Research School of Chemistry, The Australian National University, Canberra, ACT, 2601, Australia
- Nanotechnology Research Laboratory, Faculty of Engineering, University of Sydney, Sydney, NSW, 2006, Australia
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3
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Simondson D, Chatti M, Gardiner JL, Kerr BV, Hoogeveen DA, Cherepanov PV, Kuschnerus IC, Nguyen TD, Johannessen B, Chang SLY, MacFarlane DR, Hocking RK, Simonov AN. Mixed Silver–Bismuth Oxides: A Robust Oxygen Evolution Catalyst Operating at Low pH and Elevated Temperatures. ACS Catal 2022. [DOI: 10.1021/acscatal.2c03065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Darcy Simondson
- School of Chemistry, Monash University, Clayton 3800, Victoria, Australia
| | - Manjunath Chatti
- School of Chemistry, Monash University, Clayton 3800, Victoria, Australia
| | - James L. Gardiner
- School of Chemistry, Monash University, Clayton 3800, Victoria, Australia
| | - Brittany V. Kerr
- Department of Chemistry and Biotechnology, Swinburne University of Technology, Hawthorn 3122, Victoria, Australia
| | - Dijon A. Hoogeveen
- School of Chemistry, Monash University, Clayton 3800, Victoria, Australia
| | | | - Inga C. Kuschnerus
- Electron Microscope Unit, Mark Wainwright Analytical Centre, University of New South Wales, Sydney 2052, Australia
- School of Materials Science and Engineering, University of New South Wales, Sydney 2052, Australia
| | - Tam D. Nguyen
- School of Chemistry, Monash University, Clayton 3800, Victoria, Australia
| | | | - Shery L. Y. Chang
- Electron Microscope Unit, Mark Wainwright Analytical Centre, University of New South Wales, Sydney 2052, Australia
- School of Materials Science and Engineering, University of New South Wales, Sydney 2052, Australia
| | | | - Rosalie K. Hocking
- Department of Chemistry and Biotechnology, Swinburne University of Technology, Hawthorn 3122, Victoria, Australia
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4
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Kennedy BJ, Ablott TA, Avdeev M, Carter ML, Losurdo L, Saura-Muzquiz M, Thorogood KJ, Ting J, Wallwork KS, Zhang Z, Zhu H, Thorogood GJ. Synthesis and Structure of Oxygen Deficient Lead-Technetium Pyrochlore, the First Example of a Valence V Technetium Oxide. Front Chem 2021; 9:706269. [PMID: 34277573 PMCID: PMC8281135 DOI: 10.3389/fchem.2021.706269] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 06/08/2021] [Indexed: 11/13/2022] Open
Abstract
The structure of lead-technetium pyrochlore has been refined in space group Fd3¯m with a = 10.36584(2) Å using a combination of synchrotron X-ray and neutron powder diffraction data and confirmed via Electron Diffraction. The oxide is found to be oxygen deficient with a stoichiometry of Pb2Tc2O7-d. Displacive disorder of the Pb cations is evident from the refinements, as has been observed in Bi2Tc2O7-d. X-ray absorption spectroscopic measurements at the Tc K-edge demonstrate the valence of the Tc is greater than 4.0 as anticipated from the refined oxygen stoichiometry. Raman spectroscopy confirms the presence of disorder leading us to conclude that this pyrochlore is the first example of a valence V technetium oxide.
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Affiliation(s)
- Brendan J Kennedy
- School of Chemistry, The University of Sydney, Sydney, NSW, Australia
| | - Timothy A Ablott
- Nuclear Fuel Cycle, Australian Nuclear Science and Technology Organisation, Kirrawee DC, NSW, Australia
| | - Maxim Avdeev
- School of Chemistry, The University of Sydney, Sydney, NSW, Australia.,Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organisation, Kirrawee DC, NSW, Australia
| | - Melody L Carter
- Nuclear Fuel Cycle, Australian Nuclear Science and Technology Organisation, Kirrawee DC, NSW, Australia
| | - Linda Losurdo
- School of Chemistry, The University of Sydney, Sydney, NSW, Australia
| | | | - Kevin J Thorogood
- Nuclear Materials, Australian Nuclear Science and Technology Organisation, Kirrawee DC, NSW, Australia
| | - Jimmy Ting
- School of Chemistry, The University of Sydney, Sydney, NSW, Australia
| | - Kia S Wallwork
- Australian Synchrotron, Australian Nuclear Science and Technology Organisation, Clayton, VIC, Australia
| | - Zhaoming Zhang
- Nuclear Fuel Cycle, Australian Nuclear Science and Technology Organisation, Kirrawee DC, NSW, Australia
| | - Hanliang Zhu
- Nuclear Fuel Cycle, Australian Nuclear Science and Technology Organisation, Kirrawee DC, NSW, Australia
| | - Gordon J Thorogood
- Nuclear Fuel Cycle, Australian Nuclear Science and Technology Organisation, Kirrawee DC, NSW, Australia.,Department of Nuclear System Safety Engineering, Nagaoka University of Technology, Nagaoka, Japan
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5
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Farmer N, Rushmer T, Wykes J, Mallmann G. The Macquarie Deformation-DIA facility at the Australian Synchrotron: A tool for high-pressure, high-temperature experiments with synchrotron radiation. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2020; 91:114501. [PMID: 33261430 DOI: 10.1063/5.0022849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Accepted: 10/26/2020] [Indexed: 06/12/2023]
Abstract
The Macquarie University Deformation-DIA (MQ D-DIA) multi-anvil apparatus at the Australian Synchrotron provides a new experimental facility that enables simultaneous high-pressure and high-temperature in situ synchrotron experimentation in Australia. The MQ D-DIA can be easily deployed at any of a number of beamlines at the Australian Synchrotron, and we describe its installation at the x-ray absorption spectroscopy beamline, which enables in situ x-ray absorption near-edge spectroscopy and energy-scanning x-ray diffraction. A simple, reliable, and x-ray transparent high-pressure cell assembly has been developed for the D-DIA for which load/pressure and heater power/temperature relationships have been calibrated using in situ x-ray diffraction and "offline" mineral equilibration experiments. Additionally, we have mapped temperature distribution within the assembly using a new quantitative electron microprobe mapping technique developed for fine-grained polyphase samples. We are now investigating the speciation of geologically important trace elements in silicate melts (e.g., Zr, U, and Th) measured in situ under high pressure and temperature conditions corresponding to the Earth's mantle. Pressure-dependent changes in speciation influence partitioning behavior, and therefore the distribution in the Earth, of many trace elements. However, previous ex situ investigations are hampered by uncertainty as to whether high-pressure speciation can be faithfully recorded in samples recovered to ambient conditions. We present preliminary results showing an increase in the coordination number of Zr dissolved as a trace component of a sodium-rich silicate melt with pressure. These results also indicate that silicate melt composition exerts a strong influence on Zr speciation.
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Affiliation(s)
- Nicholas Farmer
- Department of Earth and Environmental Sciences, Macquarie University, Macquarie Park, NSW 2109, Australia
| | - Tracy Rushmer
- Department of Earth and Environmental Sciences, Macquarie University, Macquarie Park, NSW 2109, Australia
| | - Jeremy Wykes
- Australian Synchrotron, 800 Blackburn Road, Clayton, VIC 3168, Australia
| | - Guilherme Mallmann
- Research School of Earth Sciences, Australian National University, Acton, ACT 2601, Australia
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6
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Zhang Y, Wei T, Tran TT, Lu KT, Zhang Z, Price JR, Aharonovich I, Zheng R. [U(H 2O) 2]{[(UO 2) 10O 10(OH) 2][(UO 4)(H 2O) 2]}: A Mixed-Valence Uranium Oxide Hydrate Framework. Inorg Chem 2020; 59:12166-12175. [PMID: 32822161 DOI: 10.1021/acs.inorgchem.0c01099] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A uranium oxide hydrate framework, [U(H2O)2]{[(UO2)10O10(OH)2][(UO4)(H2O)2]} (UOF1), was synthesized hydrothermally using schoepite as a uranium precursor. The crystal strucutre of UOF1 was revealed with synchrotron single-crystal X-ray diffraction and confirmed with transmission electron miscroscopy. The typical uranyl oxide hydroxide layers similar to those in β-U3O8 are further connected via double-pentagonal-bipyramidal uranium polyhedra to form a three-dimensional (3D) framework structure with tetravalent uranium species inside the channels. The presence of mixed-valence uranium was investigated with a combination of X-ray absorption near-edge structure and diffuse reflectance spectroscopy. Apart from the major hexavalent uranium, evidence for tetravalent uranium was also found, consistent with the bond valence sum calculations. The successful preparation of UOF1 as the first pure uranium oxide hydrate framework sheds light on the structural understanding of the alteration of UO2+x as either a mineral or spent nuclear fuel.
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Affiliation(s)
- Yingjie Zhang
- Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, New South Wales 2232, Australia
| | - Tao Wei
- Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, New South Wales 2232, Australia
| | - Toan Trong Tran
- School of Mathematical and Physical Sciences, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | - Kimbal T Lu
- Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, New South Wales 2232, Australia.,School of Physics, The University of Sydney, Camperdown, New South Wales 2006, Australia
| | - Zhaoming Zhang
- Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, New South Wales 2232, Australia
| | - Jason R Price
- Australian Synchrotron, Australian Nuclear Science and Technology Organisation, 800 Blackburn Road, Clayton, Victoria 3168, Australia
| | - Igor Aharonovich
- School of Mathematical and Physical Sciences, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | - Rongkun Zheng
- School of Physics, The University of Sydney, Camperdown, New South Wales 2006, Australia
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7
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Kayser P, Orlandi F, Avdeev M, Zhang Z, Kimpton JA, Kennedy BJ. Structural Chemistry and Magnetic Properties of the Hexagonal Double Perovskite Ba 2CoOsO 6. Inorg Chem 2020; 59:6613-6622. [PMID: 32286805 DOI: 10.1021/acs.inorgchem.0c00761] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The double perovskite Ba2CoOsO6, synthesized using solid-state methods at ambient pressure, is shown as a rare example of an oxide adopting the 6L-trigonal (S.G.: P3̅m1) perovskite structure. The structure, refined using a combination of X-ray and neutron diffraction data, showed the Co and Os were ordered over the two dimer sites with additional ordering over the corner-sharing sites. Bond valence calculations show the presence of the Co(II) and Os(VI) valence states, and the latter was confirmed using X-ray absorption spectroscopy. Bulk magnetic susceptibility measurements show Ba2CoOsO6 to undergo antiferromagnetic ordering near 100 K, and neutron diffraction showed an ordered moment on the Co3, Co4, and Os2 sites; whereas the Os1/Co1 remained disordered.
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Affiliation(s)
- Paula Kayser
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia.,Centre for Science at Extreme Conditions and School of Chemistry, The University of Edinburgh, Edinburgh EH9 3JZ, U.K
| | - Fabio Orlandi
- ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Oxford, Didcot, Oxon OX11 0QX, U.K
| | - Maxim Avdeev
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia.,Australian Nuclear Science and Technology Organisation, Lucas Heights, New South Wales 2234, Australia
| | - Zhaoming Zhang
- Australian Nuclear Science and Technology Organisation, Lucas Heights, New South Wales 2234, Australia
| | - Justin A Kimpton
- Australian Synchrotron, Australian Nuclear Science and Technology Organisation, 800 Blackburn Road, Clayton, Victoria 3168, Australia
| | - Brendan J Kennedy
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
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8
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Zhang Y, Aughterson RD, Zhang Z, Wei T, Lu K, Čejka J, Karatchevtseva I. Syntheses, Crystal Structures, and Spectroscopic Studies of Uranyl Oxide Hydrate Phases with La(III)/Nd(III) Ions. Inorg Chem 2019; 58:10812-10821. [PMID: 31373489 DOI: 10.1021/acs.inorgchem.9b01102] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have synthesized two uranyl oxide hydrate (UOH) phases incorporating La(III) or Nd(III) ions under hydrothermal conditions. Investigations with scanning electron microscopy and transmission electron microscopy (TEM) revealed thin-plate morphologies with a U-to-Ln atomic ratio of 2:1 (Ln = La or Nd), while single-crystal X-ray diffraction and TEM electron diffraction studies confirmed that both UOH phases crystallized in the trigonal P31m space group with uranyl oxide layered structures incorporating La(III)/Nd(III) ions as interlayer species. Vibrational spectroscopic studies revealed typical vibrational modes for U ions, with the derived U═O bond lengths being comparable to the values reported on other UOH phases. Bond-valence-sum calculations suggest hexavalent uranium in the uranyl form, which was confirmed by the results of diffuse-reflectance and X-ray absorption near-edge structure spectroscopies. This work reports the first single-crystal structural investigation of UOH phases with Ln ions, which has significant implications in the weathering products of uraninite mineral in nature as well as the alteration products of spent nuclear fuels during interim storage and safe disposal over geological timespans.
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Affiliation(s)
- Yingjie Zhang
- Australian Nuclear Science and Technology Organisation (ANSTO) , Locked Bag 2001 , Kirrawee DC , New South Wales 2232 , Australia
| | - Robert D Aughterson
- Australian Nuclear Science and Technology Organisation (ANSTO) , Locked Bag 2001 , Kirrawee DC , New South Wales 2232 , Australia
| | - Zhaoming Zhang
- Australian Nuclear Science and Technology Organisation (ANSTO) , Locked Bag 2001 , Kirrawee DC , New South Wales 2232 , Australia
| | - Tao Wei
- Australian Nuclear Science and Technology Organisation (ANSTO) , Locked Bag 2001 , Kirrawee DC , New South Wales 2232 , Australia
| | - Kimbal Lu
- Australian Nuclear Science and Technology Organisation (ANSTO) , Locked Bag 2001 , Kirrawee DC , New South Wales 2232 , Australia
| | - Jiří Čejka
- Department of Mineralogy and Petrology , National Museum , Cirkusová 1740 , 19300 Prague 9 , Czech Republic
| | - Inna Karatchevtseva
- Australian Nuclear Science and Technology Organisation (ANSTO) , Locked Bag 2001 , Kirrawee DC , New South Wales 2232 , Australia
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9
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Chatti M, Gardiner JL, Fournier M, Johannessen B, Williams T, Gengenbach TR, Pai N, Nguyen C, MacFarlane DR, Hocking RK, Simonov AN. Intrinsically stable in situ generated electrocatalyst for long-term oxidation of acidic water at up to 80 °C. Nat Catal 2019. [DOI: 10.1038/s41929-019-0277-8] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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10
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Liang J, Levina A, Jia J, Kappen P, Glover C, Johannessen B, Lay PA. Reactivity and Transformation of Antimetastatic and Cytotoxic Rhodium(III)–Dimethyl Sulfoxide Complexes in Biological Fluids: An XAS Speciation Study. Inorg Chem 2019; 58:4880-4893. [DOI: 10.1021/acs.inorgchem.8b03477] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Jun Liang
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Aviva Levina
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Junteng Jia
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Peter Kappen
- Australian Synchrotron, ANSTO, 800 Blackburn Road, Clayton, Victoria 3168, Australia
| | - Chris Glover
- Australian Synchrotron, ANSTO, 800 Blackburn Road, Clayton, Victoria 3168, Australia
| | - Bernt Johannessen
- Australian Synchrotron, ANSTO, 800 Blackburn Road, Clayton, Victoria 3168, Australia
| | - Peter A. Lay
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
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11
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Kalniņa D, Levina A, Pei A, Gross KA, Lay PA. Synthesis, characterization and in vitro anti-cancer activity of vanadium-doped nanocrystalline hydroxyapatite. NEW J CHEM 2019. [DOI: 10.1039/c9nj03406d] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Nanocrystalline V(v)-doped hydroxyapatite and its reduced analogue (V(v) and V(iv) mixture) show promising in vitro cytotoxicity against cultured human bone cancer cells.
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Affiliation(s)
- Daina Kalniņa
- Faculty of Materials Science and Applied Chemistry
- Riga Technical University
- Riga LV1658
- Latvia
- School of Chemistry
| | - Aviva Levina
- School of Chemistry
- University of Sydney
- Sydney
- Australia
| | - Alexander Pei
- School of Chemistry
- University of Sydney
- Sydney
- Australia
- Exchange Student from Boston University
| | - Kārlis Agris Gross
- Faculty of Materials Science and Applied Chemistry
- Riga Technical University
- Riga LV1658
- Latvia
| | - Peter A. Lay
- School of Chemistry
- University of Sydney
- Sydney
- Australia
- Sydney Analytical
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12
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Injac S, Yuen AKL, Avdeev M, Orlandi F, Kennedy BJ. Structural and magnetic studies of KOsO4, a 5d1 quantum magnet oxide. Phys Chem Chem Phys 2019; 21:7261-7264. [DOI: 10.1039/c9cp00448c] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The quantum magnet KOsO4 has been characterized by a combination of X-ray and neutron diffraction techniques. This represents the first structural and magnetic characterization of a simple Os7+, S = 1/2 oxide system.
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Affiliation(s)
- Sean Injac
- School of Chemistry
- The University of Sydney
- Sydney
- Australia
| | | | - Maxim Avdeev
- School of Chemistry
- The University of Sydney
- Sydney
- Australia
- Australian Nuclear Science and Technology Organisation
| | - Fabio Orlandi
- ISIS Neutron Pulsed Facility
- Science and Technology Facilities Council
- Rutherford Appleton Laboratory
- Oxford OX11 0QX
- UK
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13
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Reynolds E, Zhang Z, Avdeev M, Thorogood GJ, Poineau F, Czerwinski KR, Kimpton JA, Kennedy BJ. Thermal Expansion Behavior in TcO 2. Toward Breaking the Tc-Tc Bond. Inorg Chem 2017; 56:9219-9224. [PMID: 28737380 DOI: 10.1021/acs.inorgchem.7b01235] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The structure of TcO2 between 25 and 1000 °C has been determined in situ using X-ray powder diffraction methods and is found to remain monoclinic in space group P21/c. Thermal expansion in TcO2 is highly anisotropic, with negative thermal expansion of the b axis observed above 700 °C. This is the result of an anomalous expansion along the a axis that is a consequence of weakening of the Tc-Tc bonds.
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Affiliation(s)
- Emily Reynolds
- Inorganic Chemistry Laboratory, University of Oxford , South Parks Road, OX1 3QR Oxford, U.K
| | - Zhaoming Zhang
- Australian Nuclear Science and Technology Organisation , Lucas Heights, New South Wales 2234, Australia
| | - Maxim Avdeev
- Australian Nuclear Science and Technology Organisation , Lucas Heights, New South Wales 2234, Australia
| | - Gordon J Thorogood
- Australian Nuclear Science and Technology Organisation , Lucas Heights, New South Wales 2234, Australia
| | - Frederic Poineau
- Department of Chemistry and Biochemistry, University of Nevada-Las Vegas , 4505 Maryland Parkway, Las Vegas, Nevada 89154, United States
| | - Kenneth R Czerwinski
- Department of Chemistry and Biochemistry, University of Nevada-Las Vegas , 4505 Maryland Parkway, Las Vegas, Nevada 89154, United States
| | - Justin A Kimpton
- Australian Synchrotron , 800 Blackburn Road, Clayton, Victoria 3168, Australia
| | - Brendan J Kennedy
- School of Chemistry, The University of Sydney , Sydney, New South Wales 2006, Australia
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14
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Kayser P, Injac S, Kennedy BJ, Vogt T, Avdeev M, Maynard-Casely HE, Zhang Z. Structural and Magnetic Properties of the Osmium Double Perovskites Ba2–xSrxYOsO6. Inorg Chem 2017; 56:6565-6575. [DOI: 10.1021/acs.inorgchem.7b00691] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Paula Kayser
- School of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia
| | - Sean Injac
- School of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia
| | - Brendan J. Kennedy
- School of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia
| | - Thomas Vogt
- Department of Chemistry and Biochemistry, University of South Carolina, 631 Sumter Street, Columbia, South Carolina 29208, United States
| | - Maxim Avdeev
- Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW 2234, Australia
| | | | - Zhaoming Zhang
- Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW 2234, Australia
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15
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Markham J, Liang J, Levina A, Mak R, Johannessen B, Kappen P, Glover CJ, Lai B, Vogt S, Lay PA. (Pentamethylcyclopentadienato)rhodium Complexes for Delivery of the Curcumin Anticancer Drug. Eur J Inorg Chem 2017. [DOI: 10.1002/ejic.201601331] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Jack Markham
- School of Chemistry; The University of Sydney; 2006 NSW Australia
| | - Jun Liang
- School of Chemistry; The University of Sydney; 2006 NSW Australia
| | - Aviva Levina
- School of Chemistry; The University of Sydney; 2006 NSW Australia
| | - Rachel Mak
- School of Chemistry; The University of Sydney; 2006 NSW Australia
| | | | - Peter Kappen
- Australian Synchrotron; 800 Blackburn Rd 3168 Clayton VIC Australia
| | - Chris J. Glover
- Australian Synchrotron; 800 Blackburn Rd 3168 Clayton VIC Australia
| | - Barry Lai
- Advanced Photon Source, Building 401; Argonne National Laboratory; 9700 South Cass Ave 60439 Lemont IL USA
| | - Stefan Vogt
- Advanced Photon Source, Building 401; Argonne National Laboratory; 9700 South Cass Ave 60439 Lemont IL USA
| | - Peter A. Lay
- School of Chemistry; The University of Sydney; 2006 NSW Australia
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16
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Reynolds E, Kennedy BJ, Avdeev M, Thorogood GJ, Zhang Z, Brand HE. Structural and spectroscopic studies of Ba2Y1−δUO6+x. J SOLID STATE CHEM 2016. [DOI: 10.1016/j.jssc.2016.07.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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17
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Murphy GL, Kennedy BJ, Kimpton JA, Gu Q, Johannessen B, Beridze G, Kowalski PM, Bosbach D, Avdeev M, Zhang Z. Nonstoichiometry in Strontium Uranium Oxide: Understanding the Rhombohedral–Orthorhombic Transition in SrUO4. Inorg Chem 2016; 55:9329-34. [DOI: 10.1021/acs.inorgchem.6b01391] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gabriel L. Murphy
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Brendan J. Kennedy
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Justin A. Kimpton
- Australian Synchrotron, 800 Blackburn
Road, Clayton, Victoria 3168, Australia
| | - Qinfen Gu
- Australian Synchrotron, 800 Blackburn
Road, Clayton, Victoria 3168, Australia
| | - Bernt Johannessen
- Australian Synchrotron, 800 Blackburn
Road, Clayton, Victoria 3168, Australia
| | - George Beridze
- Institute of Energy and Climate Research, IEK-6 Nuclear
Waste Management and Reactor Safety, Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Strasse, 52428 Jülich, Germany
- JARA High-Performance Computing, Schinkelstrasse 2, 52062 Aachen, Germany
| | - Piotr M. Kowalski
- Institute of Energy and Climate Research, IEK-6 Nuclear
Waste Management and Reactor Safety, Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Strasse, 52428 Jülich, Germany
- JARA High-Performance Computing, Schinkelstrasse 2, 52062 Aachen, Germany
| | - Dirk Bosbach
- Institute of Energy and Climate Research, IEK-6 Nuclear
Waste Management and Reactor Safety, Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Strasse, 52428 Jülich, Germany
- JARA High-Performance Computing, Schinkelstrasse 2, 52062 Aachen, Germany
| | - Maxim Avdeev
- Australian Nuclear Science and Technology Organisation, Lucas Heights, New South
Wales 2234, Australia
| | - Zhaoming Zhang
- Australian Nuclear Science and Technology Organisation, Lucas Heights, New South
Wales 2234, Australia
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18
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Best SP, Levina A, Glover C, Johannessen B, Kappen P, Lay PA. XAS spectroelectrochemistry: reliable measurement of X-ray absorption spectra from redox manipulated solutions at room temperature. JOURNAL OF SYNCHROTRON RADIATION 2016; 23:743-750. [PMID: 27140154 DOI: 10.1107/s1600577516005464] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 04/01/2016] [Indexed: 06/05/2023]
Abstract
The design and operation of a low-volume spectroelectrochemical cell for X-ray absorption spectroscopy (XAS) of solutions at room temperature is described. Fluorescence XAS measurements are obtained from samples contained in the void space of a 50 µL reticulated vitreous carbon (sponge) working electrode. Both rapid electrosynthesis and control of the effects of photoreduction are achieved by control over the flow properties of the solution through the working electrode, where a good balance between the rate of consumption of sample and the minimization of decomposition was obtained by pulsing the flow of the solution by 1-2 µL with duty cycle of ∼3 s while maintaining a small net flow rate (26-100 µL h(-1)). The performance of the cell in terms of control of the redox state of the sample and minimization of the effects of photoreduction was demonstrated by XAS measurements of aqueous solutions of the photosensitive Fe(III) species, [Fe(C2O4)3](3-), together with that of the electrogenerated [Fe(C2O4)3](4-) product. The current response from the cell during the collection of XAS spectra provides an independent measure of the stability of the sample of the measurement. The suitability of the approach for the study of small volumes of mM concentrations of protein samples was demonstrated by the measurement of the oxidized and electrochemically reduced forms of cytochrome c.
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Affiliation(s)
- Stephen P Best
- School of Chemistry, University of Melbourne, Parkville, Melbourne, Victoria 3010, Australia
| | - Aviva Levina
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Chris Glover
- Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168, Australia
| | - Bernt Johannessen
- Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168, Australia
| | - Peter Kappen
- Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168, Australia
| | - Peter A Lay
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
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19
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Gransbury GK, Kappen P, Glover CJ, Hughes JN, Levina A, Lay PA, Musgrave IF, Harris HH. Comparison of KP1019 and NAMI-A in tumour-mimetic environments. Metallomics 2016; 8:762-73. [DOI: 10.1039/c6mt00145a] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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20
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Levina A, McLeod AI, Gasparini SJ, Nguyen A, De Silva WGM, Aitken JB, Harris HH, Glover C, Johannessen B, Lay PA. Reactivity and Speciation of Anti-Diabetic Vanadium Complexes in Whole Blood and Its Components: The Important Role of Red Blood Cells. Inorg Chem 2015; 54:7753-66. [PMID: 26230577 DOI: 10.1021/acs.inorgchem.5b00665] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Reactions with blood components are crucial for controlling the antidiabetic, anticancer, and other biological activities of V(V) and V(IV) complexes. Despite extensive studies of V(V) and V(IV) reactions with the major blood proteins (albumin and transferrin), reactions with whole blood and red blood cells (RBC) have been studied rarely. A detailed speciation study of Na3[V(V)O4] (A), K4[V(IV)2O2(citr)2]·6H2O (B; citr = citrato(4-)); [V(IV)O(ma)2] (C; ma = maltolato(-)), and (NH4)[V(V)(O)2(dipic)] (D; dipic = pyridine-2,6-dicarboxylato(2-)) in whole rat blood, freshly isolated rat plasma, and commercial bovine serum using X-ray absorption near-edge structure (XANES) spectroscopy is reported. The latter two compounds are potential oral antidiabetic drugs, and the former two are likely to represent their typical decomposition products in gastrointestinal media. XANES spectral speciation was performed by principal component analysis and multiple linear regression techniques, and the distribution of V between RBC and plasma fractions was measured by electrothermal atomic absorption spectroscopy. Reactions of A, C, or D with whole blood (1.0 mM V, 1-6 h at 310 K) led to accumulation of ∼50% of total V in the RBC fraction (∼10% in the case of B), which indicated that RBC act as V carriers to peripheral organs. The spectra of V products in RBC were independent of the initial V complex, and were best fitted by a combination of V(IV)-carbohydrate (2-hydroxyacid moieties) and/or citrate (65-85%) and V(V)-protein (15-35%) models. The presence of RBC created a more reducing environment in the plasma fraction of whole blood compared with those in isolated plasma or serum, as shown by the differences in distribution of V(IV) and V(V) species in the reaction products of A-D in these media. At physiologically relevant V concentrations (<50 μM), this role of RBC may promote the formation of V(III)-transferrin as a major V carrier in the blood plasma. The results reported herein have broad implications for the roles of RBC in the transport and speciation of metal pro-drugs that have broad applications across medicine.
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Affiliation(s)
- Aviva Levina
- †School of Chemistry, The University of Sydney, Sydney NSW 2006, Australia
| | - Andrew I McLeod
- †School of Chemistry, The University of Sydney, Sydney NSW 2006, Australia
| | - Sylvia J Gasparini
- †School of Chemistry, The University of Sydney, Sydney NSW 2006, Australia
| | - Annie Nguyen
- †School of Chemistry, The University of Sydney, Sydney NSW 2006, Australia
| | | | - Jade B Aitken
- †School of Chemistry, The University of Sydney, Sydney NSW 2006, Australia.,‡Australian Synchrotron, 800 Blackburn Rd., Clayton VIC 3168, Australia
| | - Hugh H Harris
- †School of Chemistry, The University of Sydney, Sydney NSW 2006, Australia
| | - Chris Glover
- ‡Australian Synchrotron, 800 Blackburn Rd., Clayton VIC 3168, Australia
| | - Bernt Johannessen
- ‡Australian Synchrotron, 800 Blackburn Rd., Clayton VIC 3168, Australia
| | - Peter A Lay
- †School of Chemistry, The University of Sydney, Sydney NSW 2006, Australia
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21
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Blanchard PER, Reynolds E, Kennedy BJ, Ling CD, Zhang Z, Thorogood G, Cowie BCC, Thomsen L. An unconventional method for measuring the Tc L3-edge of technetium compounds. JOURNAL OF SYNCHROTRON RADIATION 2014; 21:1275-1281. [PMID: 25343795 DOI: 10.1107/s1600577514014891] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Accepted: 06/24/2014] [Indexed: 06/04/2023]
Abstract
Tc L3-edge XANES spectra have been collected on powder samples of SrTcO3 (octahedral Tc(4+)) and NH4TcO4 (tetrahedral Tc(7+)) immobilized in an epoxy resin. Features in the Tc L3-edge XANES spectra are compared with the pre-edge feature of the Tc K-edge as well as other 4d transition metal L3-edges. Evidence of crystal field splitting is obvious in the Tc L3-edge, which is sensitive to the coordination number and oxidation state of the Tc cation. The Tc L3 absorption edge energy difference between SrTcO3 (Tc(4+)) and NH4TcO4 (Tc(7+)) shows that the energy shift at the Tc L3-edge is an effective tool for studying changes in the oxidation states of technetium compounds. The Tc L3-edge spectra are compared with those obtained from Mo and Ru oxide standards with various oxidation states and coordination environments. Most importantly, fitting the Tc L3-edge to component peaks can provide direct evidence of crystal field splitting that cannot be obtained from the Tc K-edge.
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Affiliation(s)
| | - Emily Reynolds
- School of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia
| | - Brendan J Kennedy
- School of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia
| | - Chris D Ling
- School of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia
| | - Zhaoming Zhang
- Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW 2234, Australia
| | - Gordon Thorogood
- Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW 2234, Australia
| | - Bruce C C Cowie
- Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168, Australia
| | - Lars Thomsen
- Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168, Australia
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22
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Levina A, McLeod AI, Lay PA. Vanadium Speciation by XANES Spectroscopy: A Three-Dimensional Approach. Chemistry 2014; 20:12056-60. [DOI: 10.1002/chem.201403993] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Indexed: 11/09/2022]
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23
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Hocking RK, Malaeb R, Gates WP, Patti AF, Chang SLY, Devlin G, MacFarlane DR, Spiccia L. Formation of a Nanoparticulate Birnessite-Like Phase in Purported Molecular Water Oxidation Catalyst Systems. ChemCatChem 2014. [DOI: 10.1002/cctc.201400066] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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24
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Boland DD, Collins RN, Glover CJ, David Waite T. An in situ quick-EXAFS and redox potential study of the Fe(II)-catalysed transformation of ferrihydrite. Colloids Surf A Physicochem Eng Asp 2013. [DOI: 10.1016/j.colsurfa.2013.02.009] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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25
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Ohlin CA, Harley SJ, McAlpin JG, Hocking RK, Mercado BQ, Johnson RL, Villa EM, Fidler MK, Olmstead MM, Spiccia L, Britt RD, Casey WH. Rates of water exchange for two cobalt(II) heteropolyoxotungstate compounds in aqueous solution. Chemistry 2011; 17:4408-17. [PMID: 21416515 DOI: 10.1002/chem.201003550] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2010] [Indexed: 11/12/2022]
Abstract
Polyoxometalate ions are used as ligands in water-oxidation processes related to solar energy production. An important step in these reactions is the association and dissociation of water from the catalytic sites, the rates of which are unknown. Here we report the exchange rates of water ligated to Co(II) atoms in two polyoxotungstate sandwich molecules using the (17)O-NMR-based Swift-Connick method. The compounds were the [Co(4)(H(2)O)(2)(B-α-PW(9)O(34))(2)](10-) and the larger αββα-[Co(4)(H(2)O)(2)(P(2)W(15)O(56))(2)](16-) ions, each with two water molecules bound trans to one another in a Co(II) sandwich between the tungstate ligands. The clusters, in both solid and solution state, were characterized by a range of methods, including NMR, EPR, FT-IR, UV-Vis, and EXAFS spectroscopy, ESI-MS, single-crystal X-ray crystallography, and potentiometry. For [Co(4)(H(2)O)(2)(B-α-PW(9)O(34))(2)](10-) at pH 5.4, we estimate: k(298)=1.5(5)±0.3×10(6) s(-1), ΔH(≠)=39.8±0.4 kJ mol(-1), ΔS(≠)=+7.1±1.2 J mol(-1) K(-1) and ΔV(≠)=5.6 ±1.6 cm(3) mol(-1). For the Wells-Dawson sandwich cluster (αββα-[Co(4)(H(2)O)(2)(P(2)W(15)O(56))(2)](16-)) at pH 5.54, we find: k(298)=1.6(2)±0.3×10(6) s(-1), ΔH(≠)=27.6±0.4 kJ mol(-1) ΔS(≠)=-33±1.3 J mol(-1) K(-1) and ΔV(≠)=2.2±1.4 cm(3) mol(-1) at pH 5.2. The molecules are clearly stable and monospecific in slightly acidic solutions, but dissociate in strongly acidic solutions. This dissociation is detectable by EPR spectroscopy as S=3/2 Co(II) species (such as the [Co(H(2)O)(6)](2+) monomer ion) and by the significant reduction of the Co-Co vector in the XAS spectra.
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Affiliation(s)
- C André Ohlin
- Department of Chemistry, University of California, Davis, California 95616, USA
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