1
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Shakibi Nia N, Griesser C, Mairegger T, Wernig EM, Bernardi J, Portenkirchner E, Penner S, Kunze-Liebhäuser J. Titanium Oxycarbide as Platinum-Free Electrocatalyst for Ethanol Oxidation. ACS Catal 2024; 14:324-329. [PMID: 38205023 PMCID: PMC10775143 DOI: 10.1021/acscatal.3c04097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 12/06/2023] [Accepted: 12/06/2023] [Indexed: 01/12/2024]
Abstract
The compound material titanium oxycarbide (TiOC) is found to be an effective electrocatalyst for the electrochemical oxidation of ethanol to CO2. The complete course of this reaction is one of the main challenges in direct ethanol fuel cells (DEFCs). While TiOC has previously been investigated as catalyst support material only, in this study we show that TiOC alone is able to oxidize ethanol to acetaldehyde without the need of expensive noble metal catalysts like Pt. It is suggested that this behavior is attributed to the presence of both undercoordinated sites, which allow ethanol to adsorb, and oxygenated sites, which facilitate the activation of water. This is a milestone in DEFC research and development and opens up innovative possibilities for the design of catalyst materials for intermediate temperature fuel cells.
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Affiliation(s)
- Niusha Shakibi Nia
- Institute
of Physical Chemistry, University of Innsbruck, 6020 Innsbruck, Austria
| | - Christoph Griesser
- Institute
of Physical Chemistry, University of Innsbruck, 6020 Innsbruck, Austria
| | - Thomas Mairegger
- Institute
of Physical Chemistry, University of Innsbruck, 6020 Innsbruck, Austria
| | - Eva-Maria Wernig
- Institute
of Physical Chemistry, University of Innsbruck, 6020 Innsbruck, Austria
| | - Johannes Bernardi
- USTEM, Technische Universität Wien, Stadionalle 2, 1020 Wien, Austria
| | | | - Simon Penner
- Institute
of Physical Chemistry, University of Innsbruck, 6020 Innsbruck, Austria
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2
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Grützmacher PG, Cutini M, Marquis E, Rodríguez Ripoll M, Riedl H, Kutrowatz P, Bug S, Hsu CJ, Bernardi J, Gachot C, Erdemir A, Righi MC. Se Nanopowder Conversion into Lubricious 2D Selenide Layers by Tribochemical Reactions. Adv Mater 2023; 35:e2302076. [PMID: 37247210 DOI: 10.1002/adma.202302076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Revised: 05/10/2023] [Indexed: 05/30/2023]
Abstract
Transition metal dichalcogenide (TMD) coatings have attracted enormous scientific and industrial interest due to their outstanding tribological behavior. The paradigmatic example is MoS2 , even though selenides and tellurides have demonstrated superior tribological properties. Here, an innovative in operando conversion of Se nanopowders into lubricious 2D selenides, by sprinkling them onto sliding metallic surfaces coated with Mo and W thin films, is described. Advanced material characterization confirms the tribochemical formation of a thin tribofilm containing selenides, reducing the coefficient of friction down to below 0.1 in ambient air, levels typically reached using fully formulated oils. Ab initio molecular dynamics simulations under tribological conditions reveal the atomistic mechanisms that result in the shear-induced synthesis of selenide monolayers from nanopowders. The use of Se nanopowder provides thermal stability and prevents outgassing in vacuum environments. Additionally, the high reactivity of the Se nanopowder with the transition metal coating in the conditions prevailing in the contact interface yields highly reproducible results, making it particularly suitable for the replenishment of sliding components with solid lubricants, avoiding the long-lasting problem of TMD-lubricity degradation caused by environmental molecules. The suggested straightforward approach demonstrates an unconventional and smart way to synthesize TMDs in operando and exploit their friction- and wear-reducing impact.
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Affiliation(s)
- Philipp G Grützmacher
- Institute for Engineering Design and Product Development, Tribology Research Division, TU Wien, Vienna, 1060, Austria
| | - Michele Cutini
- Department of Physics and Astronomy, Alma Mater Studiorum - University of Bologna, Bologna, 40127, Italy
| | - Edoardo Marquis
- Department of Physics and Astronomy, Alma Mater Studiorum - University of Bologna, Bologna, 40127, Italy
| | | | - Helmut Riedl
- Institute of Materials Science and Technology, TU Wien, Vienna, 1060, Austria
| | - Philip Kutrowatz
- Institute of Materials Science and Technology, TU Wien, Vienna, 1060, Austria
| | - Stefan Bug
- Institute for Engineering Design and Product Development, Tribology Research Division, TU Wien, Vienna, 1060, Austria
| | - Chia-Jui Hsu
- Institute for Engineering Design and Product Development, Tribology Research Division, TU Wien, Vienna, 1060, Austria
| | - Johannes Bernardi
- University Service Centre for Transmission Electron Microscopy (USTEM), TU Wien, Vienna, 1040, Austria
| | - Carsten Gachot
- Institute for Engineering Design and Product Development, Tribology Research Division, TU Wien, Vienna, 1060, Austria
| | - Ali Erdemir
- J. Mike Walker '66 Department of Mechanical Engineering, Texas A&M University, College Station, TX, 77843, USA
| | - Maria Clelia Righi
- Department of Physics and Astronomy, Alma Mater Studiorum - University of Bologna, Bologna, 40127, Italy
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3
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Gazil O, Bernardi J, Lassus A, Virgilio N, Unterlass MM. Urethane functions can reduce metal salts under hydrothermal conditions: synthesis of noble metal nanoparticles on flexible sponges applied in semi-automated organic reduction. J Mater Chem A Mater 2023; 11:12703-12712. [PMID: 37346738 PMCID: PMC10281335 DOI: 10.1039/d2ta09405c] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 02/04/2023] [Indexed: 06/23/2023]
Abstract
We report an additive-free one-pot hydrothermal synthesis of Au, Ag, Pd, and alloy AuPd nanoparticles (NPs) anchored on commercial polyurethane (PU) foams. While unable to reduce the precursor metal salts at room temperature, PU is able to serve as a reducing agent under hydrothermal conditions. The resulting NP@PU sponge materials perform comparably to reported state-of-the-art reduction catalysts, and are additionally very well suited for use in semi-automated synthesis: the NP anchoring is strong enough and the support flexible enough to be used as a 'catalytic sponge' that can be manipulated with a robotic arm, i.e., be repeatedly dipped into and drawn out of solutions, wrung out, and re-soaked.
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Affiliation(s)
- Olivier Gazil
- Universität Konstanz, Department of Chemistry, Solid State Chemistry Universitätsstrasse 10 D-78464 Konstanz Germany
- CREPEC, Department of Chemical Engineering, Polytechnique Montréal C.P. 6079 Succursale Centre-Ville Montréal Québec H3C 3A7 Canada
| | - Johannes Bernardi
- University Service Centre for Transmission Electron Microscopy, Vienna University of Technology Wiedner Hauptstrasse 8-10/137 A-1040 Vienna Austria
| | - Arthur Lassus
- CREPEC, Department of Chemical Engineering, Polytechnique Montréal C.P. 6079 Succursale Centre-Ville Montréal Québec H3C 3A7 Canada
| | - Nick Virgilio
- CREPEC, Department of Chemical Engineering, Polytechnique Montréal C.P. 6079 Succursale Centre-Ville Montréal Québec H3C 3A7 Canada
| | - Miriam M Unterlass
- Universität Konstanz, Department of Chemistry, Solid State Chemistry Universitätsstrasse 10 D-78464 Konstanz Germany
- Center for Molecular Medicine of the Austrian Academy of Sciences (CeMM) Lazarettgasse 14, AKH BT25.3 1090 Vienna Austria
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4
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Zeininger J, Raab M, Suchorski Y, Buhr S, Stöger-Pollach M, Bernardi J, Rupprechter G. Reaction Modes on a Single Catalytic Particle: Nanoscale Imaging and Micro-Kinetic Modeling. ACS Catal 2022; 12:12774-12785. [PMID: 36313520 PMCID: PMC9594309 DOI: 10.1021/acscatal.2c02901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 08/04/2022] [Indexed: 11/29/2022]
Abstract
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The kinetic behavior of individual Rh(hkl) nanofacets
coupled in a common reaction system was studied using the apex of
a curved rhodium microcrystal (radius of 0.65 μm) as a model
of a single catalytic particle and field electron microscopy for in
situ imaging of catalytic hydrogen oxidation. Depending on the extent
of interfacet coupling via hydrogen diffusion, different oscillating
reaction modes were observed including highly unusual multifrequential
oscillations: differently oriented nanofacets oscillated with differing
frequencies despite their immediate neighborhood. The transitions
between different modes were induced by variations in the particle
temperature, causing local surface reconstructions, which create locally
protruding atomic rows. These atomic rows modified the coupling strength
between individual nanofacets and caused the transitions between different
oscillating modes. Effects such as entrainment, frequency locking,
and reconstruction-induced collapse of spatial coupling were observed.
To reveal the origin of the different experimentally observed effects,
microkinetic simulations were performed for a network of 105 coupled
oscillators, modeling the individual nanofacets communicating via
hydrogen surface diffusion. The calculated behavior of the oscillators,
the local frequencies, and the varying degree of spatial synchronization
describe the experimental observations well.
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Affiliation(s)
- Johannes Zeininger
- Institute of Materials Chemistry, TU Wien, Getreidemarkt 9, 1060Vienna, Austria
| | - Maximilian Raab
- Institute of Materials Chemistry, TU Wien, Getreidemarkt 9, 1060Vienna, Austria
| | - Yuri Suchorski
- Institute of Materials Chemistry, TU Wien, Getreidemarkt 9, 1060Vienna, Austria
| | - Sebastian Buhr
- Institute of Materials Chemistry, TU Wien, Getreidemarkt 9, 1060Vienna, Austria
| | - Michael Stöger-Pollach
- University Service Center for Transmission Electron Microscopy, TU Wien, Wiedner Hauptstraße 8-10, 1040Vienna, Austria
| | - Johannes Bernardi
- University Service Center for Transmission Electron Microscopy, TU Wien, Wiedner Hauptstraße 8-10, 1040Vienna, Austria
| | - Günther Rupprechter
- Institute of Materials Chemistry, TU Wien, Getreidemarkt 9, 1060Vienna, Austria
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5
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Mohammadi A, Praty C, Farzi A, Soleimanzadeh H, Schwarz S, Stöger-Pollach M, Bernardi J, Penner S, Niaei A. Influence of CeO2 and WO3 Addition to Impregnated V2O5/TiO2 Catalysts on the Selective Catalytic Reduction of NOx with NH3. Catal Letters 2022. [DOI: 10.1007/s10562-022-04108-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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6
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Thurner CW, Bonmassar N, Winkler D, Haug L, Ploner K, Delir Kheyrollahi Nezhad P, Drexler X, Mohammadi A, van Aken PA, Kunze-Liebhäuser J, Niaei A, Bernardi J, Klötzer B, Penner S. Who Does the Job? How Copper Can Replace Noble Metals in Sustainable Catalysis by the Formation of Copper–Mixed Oxide Interfaces. ACS Catal 2022; 12:7696-7708. [PMID: 35799767 PMCID: PMC9251726 DOI: 10.1021/acscatal.2c01584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 05/23/2022] [Indexed: 11/28/2022]
Abstract
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Following the need
for an innovative catalyst and material design
in catalysis, we provide a comparative approach using pure and Pd-doped
LaCuxMn1–xO3 (x = 0.3 and 0.5) perovskite
catalysts to elucidate the beneficial role of the Cu/perovskite and
the promoting effect of CuyPdx/perovskite interfaces developing in situ under model NO + CO reaction conditions. The observed bifunctional
synergism in terms of activity and N2 selectivity is essentially
attributed to an oxygen-deficient perovskite interface, which provides
efficient NO activation sites in contact with in situ exsolved surface-bound monometallic Cu and bimetallic CuPd nanoparticles.
The latter promotes the decomposition of the intermediate N2O at low temperatures, enhancing the selectivity toward N2. We show that the intelligent Cu/perovskite interfacial design is
the prerequisite to effectively replace noble metals by catalytically
equally potent metal–mixed-oxide interfaces. We have provided
the proof of principle for the NO + CO test reaction but anticipate
the extension to a universal concept applicable to similar materials
and reactions.
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Affiliation(s)
- Christoph W. Thurner
- Department of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
| | - Nicolas Bonmassar
- Max Plank Institute for Solid State Research, Heisenbergstaße 1, D-70569 Stuttgart, Germany
| | - Daniel Winkler
- Department of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
| | - Leander Haug
- Department of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
| | - Kevin Ploner
- Department of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
| | - Parastoo Delir Kheyrollahi Nezhad
- Department of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
- Reactor & Catalyst Research Laboratory, Department of Chemical and Petroleum Engineering, University of Tabriz, 29 Bahman Boulevard, Tabriz 51666-16471, Iran
| | - Xaver Drexler
- Department of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
| | - Asghar Mohammadi
- Department of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
- Reactor & Catalyst Research Laboratory, Department of Chemical and Petroleum Engineering, University of Tabriz, 29 Bahman Boulevard, Tabriz 51666-16471, Iran
| | - Peter A. van Aken
- Max Plank Institute for Solid State Research, Heisenbergstaße 1, D-70569 Stuttgart, Germany
| | - Julia Kunze-Liebhäuser
- Department of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
| | - Aligholi Niaei
- Reactor & Catalyst Research Laboratory, Department of Chemical and Petroleum Engineering, University of Tabriz, 29 Bahman Boulevard, Tabriz 51666-16471, Iran
| | - Johannes Bernardi
- University Service Centre for Transmission Electron Microscopy (USTEM), Technische Universität Wien, Wiedner Hauptstraße 8-10/057-02, A-1040 Wien, Austria
| | - Bernhard Klötzer
- Department of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
| | - Simon Penner
- Department of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
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7
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Batool S, Nandan SP, Myakala SN, Rajagopal A, Schubert JS, Ayala P, Naghdi S, Saito H, Bernardi J, Streb C, Cherevan A, Eder D. Surface Anchoring and Active Sites of [Mo 3S 13] 2- Clusters as Co-Catalysts for Photocatalytic Hydrogen Evolution. ACS Catal 2022; 12:6641-6650. [PMID: 35692252 PMCID: PMC9171716 DOI: 10.1021/acscatal.2c00972] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 03/31/2022] [Indexed: 11/30/2022]
Abstract
![]()
Achieving light-driven
splitting of water with high efficiency
remains a challenging task on the way to solar fuel exploration. In
this work, to combine the advantages of heterogeneous and homogeneous
photosystems, we covalently anchor noble-metal- and carbon-free thiomolybdate
[Mo3S13]2– clusters onto photoactive
metal oxide supports to act as molecular co-catalysts for photocatalytic
water splitting. We demonstrate that strong and surface-limited binding
of the [Mo3S13]2– to the oxide
surfaces takes place. The attachment involves the loss of the majority
of the terminal S22– groups, upon which
Mo–O–Ti bonds with the hydroxylated TiO2 surface
are established. The heterogenized [Mo3S13]2– clusters are active and stable co-catalysts for the
light-driven hydrogen evolution reaction (HER) with performance close
to the level of the benchmark Pt. Optimal HER rates are achieved for
2 wt % cluster loadings, which we relate to the accessibility of the
TiO2 surface required for efficient hole scavenging. We
further elucidate the active HER sites by applying thermal post-treatments
in air and N2. Our data demonstrate the importance of the
trinuclear core of the [Mo3S13]2– cluster and suggest bridging S22– and
vacant coordination sites at the Mo centers as likely HER active sites.
This work provides a prime example for the successful heterogenization
of an inorganic molecular cluster as a co-catalyst for light-driven
HER and gives the incentive to explore other thio(oxo)metalates.
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Affiliation(s)
- Samar Batool
- Institute of Materials Chemistry, TU Wien, Getreidemarkt 9/BC/02, 1060 Vienna, Austria
| | - Sreejith P. Nandan
- Institute of Materials Chemistry, TU Wien, Getreidemarkt 9/BC/02, 1060 Vienna, Austria
| | | | - Ashwene Rajagopal
- Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Jasmin S. Schubert
- Institute of Materials Chemistry, TU Wien, Getreidemarkt 9/BC/02, 1060 Vienna, Austria
| | - Pablo Ayala
- Institute of Materials Chemistry, TU Wien, Getreidemarkt 9/BC/02, 1060 Vienna, Austria
| | - Shaghayegh Naghdi
- Institute of Materials Chemistry, TU Wien, Getreidemarkt 9/BC/02, 1060 Vienna, Austria
| | - Hikaru Saito
- Institute for Materials Chemistry and Engineering, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580, Japan
| | - Johannes Bernardi
- University Service Centre for Transmission Electron Microscopy (USTEM), TU Wien, Wiedner Hauptstraße 8-10, 1040 Vienna, Austria
| | - Carsten Streb
- Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
- Department of Chemistry, Johannes Gutenberg University Mainz, Duesbergweg 10-14, 55128 Mainz, Germany
| | - Alexey Cherevan
- Institute of Materials Chemistry, TU Wien, Getreidemarkt 9/BC/02, 1060 Vienna, Austria
| | - Dominik Eder
- Institute of Materials Chemistry, TU Wien, Getreidemarkt 9/BC/02, 1060 Vienna, Austria
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8
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Kalantari N, Bekheet MF, Nezhad PDK, Back JO, Farzi A, Penner S, Delibaş NÇ, Schwarz S, Bernardi J, Salari D, Niaei A. Effect of chromium and boron incorporation methods on structural and catalytic properties of hierarchical ZSM-5 in the methanol-to-propylene process. J IND ENG CHEM 2022. [DOI: 10.1016/j.jiec.2022.03.049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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9
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Riedl C, Siebenhofer M, Nenning A, Friedbacher G, Weiss M, Rameshan C, Bernardi J, Limbeck A, Kubicek M, Opitz AK, Fleig J. Performance modulation through selective, homogenous surface doping of lanthanum strontium ferrite electrodes revealed by in situ PLD impedance measurements. J Mater Chem A Mater 2022; 10:2973-2986. [PMID: 35223041 PMCID: PMC8823903 DOI: 10.1039/d1ta08634k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 12/03/2021] [Indexed: 06/14/2023]
Abstract
Accelerating the oxygen reduction kinetics of solid oxide fuel cell (SOFC) cathodes is crucial to improve their efficiency and thus to provide the basis for an economically feasible application of intermediate temperature SOFCs. In this work, minor amounts of Pt were doped into lanthanum strontium ferrite (LSF) thin film electrodes to modulate the material's oxygen exchange performance. Surprisingly, Pt was found to be incorporated on the B-site of the perovskite electrode as non metallic Pt4+. The polarization resistance of LSF thin film electrodes with and without additional Pt surface doping was compared directly after film growth employing in situ electrochemical impedance spectroscopy inside a PLD chamber (i-PLD). This technique enables observation of the polarization resistance of pristine electrodes unaltered by degradation or any external contamination of the electrode surface. Moreover, growth of multi-layers of materials with different compositions on the very same single crystalline electrolyte substrate combined with in situ impedance measurements allow excellent comparability of different materials. Even a 5 nm layer of Pt doped LSF (1.5 at% Pt), i.e. a Pt loading of 80 ng cm-2, improved the polarization resistance by a factor of about 2.5. In addition, p(O2) and temperature dependent impedance measurements on both pure and Pt doped LSF were performed in situ and obtained similar activation energies and p(O2) dependence of the polarization resistance, which allow us to make far reaching mechanistic conclusions indicating that Pt4+ introduces additional active sites.
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Affiliation(s)
- Christoph Riedl
- Institute of Chemical Technologies and Analytics, TU Wien Getreidemarkt 9-E164 1060 Vienna Austria
| | - Matthäus Siebenhofer
- Institute of Chemical Technologies and Analytics, TU Wien Getreidemarkt 9-E164 1060 Vienna Austria
- CEST Kompetenzzentrum für elektrochemische Oberflächentechnologie GmbH TFZ - Wiener Neustadt Viktor-Kaplan-Strasse 2 2700 Wiener Neustadt Austria
| | - Andreas Nenning
- Institute of Chemical Technologies and Analytics, TU Wien Getreidemarkt 9-E164 1060 Vienna Austria
| | - Gernot Friedbacher
- Institute of Chemical Technologies and Analytics, TU Wien Getreidemarkt 9-E164 1060 Vienna Austria
| | - Maximilian Weiss
- Institute of Chemical Technologies and Analytics, TU Wien Getreidemarkt 9-E164 1060 Vienna Austria
| | - Christoph Rameshan
- Institute of Materials Chemistry, TU Wien Getreidemarkt 9-E165-PC 1060 Vienna Austria
| | - Johannes Bernardi
- USTEM Universitäre Service-Einrichtung für Transmissions-Elektronenmikroskopie, TU Wien Wiedner Hauptstrasse. 8-10 1040 Wien Austria
| | - Andreas Limbeck
- Institute of Chemical Technologies and Analytics, TU Wien Getreidemarkt 9-E164 1060 Vienna Austria
| | - Markus Kubicek
- Institute of Chemical Technologies and Analytics, TU Wien Getreidemarkt 9-E164 1060 Vienna Austria
| | - Alexander Karl Opitz
- Institute of Chemical Technologies and Analytics, TU Wien Getreidemarkt 9-E164 1060 Vienna Austria
| | - Juergen Fleig
- Institute of Chemical Technologies and Analytics, TU Wien Getreidemarkt 9-E164 1060 Vienna Austria
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10
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Delir Kheyrollahi Nezhad P, Bekheet MF, Bonmassar N, Gili A, Kamutzki F, Gurlo A, Doran A, Schwarz S, Bernardi J, Praetz S, Niaei A, Farzi A, Penner S. Elucidating the role of earth alkaline doping in perovskite-based methane dry reforming catalysts. Catal Sci Technol 2022; 12:1229-1244. [PMID: 35310768 PMCID: PMC8859525 DOI: 10.1039/d1cy02044g] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 01/05/2022] [Indexed: 11/21/2022]
Abstract
To elucidate the role of earth alkaline doping in perovskite-based dry reforming of methane (DRM) catalysts, we embarked on a comparative and exemplary study of a Ni-based Sm perovskite with and without Sr doping. While the Sr-doped material appears as a structure-pure Sm1.5Sr0.5NiO4 Ruddlesden Popper structure, the undoped material is a NiO/monoclinic Sm2O3 composite. Hydrogen pre-reduction or direct activation in the DRM mixture in all cases yields either active Ni/Sm2O3 or Ni/Sm2O3/SrCO3 materials, with albeit different short-term stability and deactivation behavior. The much smaller Ni particle size after hydrogen reduction of Sm1.5Sr0.5NiO4, and of generally all undoped materials stabilizes the short and long-term DRM activity. Carbon dioxide reactivity manifests itself in the direct formation of SrCO3 in the case of Sm1.5Sr0.5NiO4, which is dominant at high temperatures. For Sm1.5Sr0.5NiO4, the CO : H2 ratio exceeds 1 at these temperatures, which is attributed to faster direct carbon dioxide conversion to SrCO3 without catalytic DRM reactivity. As no Sm2O2CO3 surface or bulk phase as a result of carbon dioxide activation was observed for any material – in contrast to La2O2CO3 – we suggest that oxy-carbonate formation plays only a minor role for DRM reactivity. Rather, we identify surface graphitic carbon as the potentially reactive intermediate. Graphitic carbon has already been shown as a crucial reaction intermediate in metal-oxide DRM catalysts and appears both for Sm1.5Sr0.5NiO4 and NiO/monoclinic Sm2O3 after reaction as crystalline structure. It is significantly more pronounced for the latter due to the higher amount of oxygen-deficient monoclinic Sm2O3 facilitating carbon dioxide activation. Despite the often reported beneficial role of earth alkaline dopants in DRM catalysis, we show that the situation is more complex. In our studies, the detrimental role of earth alkaline doping manifests itself in the exclusive formation of the sole stable carbonated species and a general destabilization of the Ni/monoclinic Sm2O3 interface by favoring Ni particle sintering. To elucidate the role of earth alkaline doping in perovskite-based dry reforming of methane (DRM) catalysts, we embarked on a comparative and exemplary study of a Ni-based Sm perovskite with and without Sr doping.![]()
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Affiliation(s)
- Parastoo Delir Kheyrollahi Nezhad
- Reactor & Catalyst Research Lab, Department of Chemical Engineering, Faculty of Chemical and Petroleum Engineering, University of Tabriz, Tabriz, Iran
| | - Maged F. Bekheet
- Fachgebiet Keramische Werkstoffe/Chair of Advanced Ceramic Materials, Institut für Werkstoffwissenschaften und -technologien, Technische Universität Berlin, Hardenbergstr. 40, 10623 Berlin, Germany
| | - Nicolas Bonmassar
- Department of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
| | - Albert Gili
- Institut für Chemie, Technische Universität Berlin, Sekretariat TC 8, Straße des 17. Juni 124, 10623 Berlin, Germany
| | - Franz Kamutzki
- Fachgebiet Keramische Werkstoffe/Chair of Advanced Ceramic Materials, Institut für Werkstoffwissenschaften und -technologien, Technische Universität Berlin, Hardenbergstr. 40, 10623 Berlin, Germany
| | - Aleksander Gurlo
- Fachgebiet Keramische Werkstoffe/Chair of Advanced Ceramic Materials, Institut für Werkstoffwissenschaften und -technologien, Technische Universität Berlin, Hardenbergstr. 40, 10623 Berlin, Germany
| | - Andrew Doran
- Advanced Light Source, Lawrence Berkeley National Laboratory Berkeley, California 94720, USA
| | - Sabine Schwarz
- University Service Center for Transmission Electron Microscopy, TU Wien, Wiedner Hauptstrasse 8-10, A-1040 Vienna, Austria
| | - Johannes Bernardi
- University Service Center for Transmission Electron Microscopy, TU Wien, Wiedner Hauptstrasse 8-10, A-1040 Vienna, Austria
| | - Sebastian Praetz
- Institute of Optics and Atomic Physics, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
| | - Aligholi Niaei
- Reactor & Catalyst Research Lab, Department of Chemical Engineering, Faculty of Chemical and Petroleum Engineering, University of Tabriz, Tabriz, Iran
| | - Ali Farzi
- Reactor & Catalyst Research Lab, Department of Chemical Engineering, Faculty of Chemical and Petroleum Engineering, University of Tabriz, Tabriz, Iran
| | - Simon Penner
- Department of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
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11
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Nedelkovski V, Andriotis OG, Wieland K, Gasser C, Steiger-Thirsfeld A, Bernardi J, Lendl B, Pretterklieber ML, Thurner PJ. Microbeam bending of hydrated human cortical bone lamellae from the central region of the body of femur shows viscoelastic behaviour. J Mech Behav Biomed Mater 2021; 125:104815. [PMID: 34678618 DOI: 10.1016/j.jmbbm.2021.104815] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 04/30/2021] [Accepted: 09/03/2021] [Indexed: 12/27/2022]
Abstract
Bone is a biological tissue with unique mechanical properties, owing to a complex hierarchical structure ranging from the nanoscale up to the macroscale. To better understand bone mechanics, investigation of mechanical properties of all structural elements at every hierarchical level and how they interact is necessary. Testing of bone structures at the lower microscale, e.g. bone lamellae, has been least performed and remains a challenge. Focused ion beam (FIB) milling is an attractive technique for machining microscopic samples from bone material and performing mechanical testing at the microscale using atomic force microscopy (AFM) and nanoindentation setups. So far, reported studies at this length scale have been performed on bone samples of animal origin, mostly in a dehydrated state, except for one study. Here we present an AFM-based microbeam bending method for performing bending measurements in both dehydrated and rehydrated conditions at the microscale. Single lamella bone microbeams of four human donors, aged 65-94 yrs, were machined via FIB and tested both in air and fully submerged in Hank's Balanced Salt Solution (HBSS) to investigate the effect of (de)hydration and to a certain extent, of age, on bone mechanics. Bending moduli were found to reduce up to 5 times after 2 h of rehydration and no trend of change in bending moduli with respect to age could be observed. Mechanical behavior changed from almost purely elastic to viscoelastic upon rehydration and a trend of lower dissipated energy in samples from older donors could be observed in the rehydrated state. These results confirm directly the importance of water for the mechanical properties of bone tissue at the microscale. Moreover, the trend of lowered capability of energy dissipation in older donors may contribute to a decrease of fracture toughness and thus an increase in bone fragility with age.
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Affiliation(s)
- Vedran Nedelkovski
- Institute of Lightweight Design and Structural Biomechanics, TU Wien, 1060, Vienna, Austria
| | - Orestis G Andriotis
- Institute of Lightweight Design and Structural Biomechanics, TU Wien, 1060, Vienna, Austria
| | - Karin Wieland
- Institute of Chemical Technologies and Analytics, TU Wien, 1060, Vienna, Austria
| | - Christoph Gasser
- Institute of Chemical Technologies and Analytics, TU Wien, 1060, Vienna, Austria
| | | | - Johannes Bernardi
- University Service Center for Transmission Electron Microscopy, TU Wien, 1040, Vienna, Austria
| | - Bernhard Lendl
- Institute of Chemical Technologies and Analytics, TU Wien, 1060, Vienna, Austria
| | - Michael L Pretterklieber
- Center for Anatomy and Cell Biology, Division of Anatomy, Medical University of Vienna, 1090, Vienna, Austria; Division of Macroscopic and Clinical Anatomy, Medical University Graz, 8010, Graz, Austria
| | - Philipp J Thurner
- Institute of Lightweight Design and Structural Biomechanics, TU Wien, 1060, Vienna, Austria.
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12
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Ploner K, Doran A, Kunz M, Gili A, Gurlo A, Köwitsch N, Armbrüster M, Bernardi J, Watschinger M, Penner S. Steering the methanol steam reforming reactivity of intermetallic Cu-In compounds by redox activation: stability vs. formation of an intermetallic compound-oxide interface. Catal Sci Technol 2021; 11:5518-5533. [PMID: 34457240 PMCID: PMC8365629 DOI: 10.1039/d1cy00913c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Accepted: 07/19/2021] [Indexed: 11/21/2022]
Abstract
To compare the inherent methanol steam reforming properties of intermetallic compounds and a corresponding intermetallic compound–oxide interface, we selected the Cu–In system as a model to correlate the stability limits, self-activation and redox activation properties with the catalytic performance. Three distinct intermetallic Cu–In compounds – Cu7In3, Cu2In and Cu11In9 – were studied both in an untreated and redox-activated state resulting from alternating oxidation–reduction cycles. The stability of all studied intermetallic compounds during methanol steam reforming (MSR) operation is essentially independent of the initial stoichiometry and all accordingly resist substantial structural changes. The inherent activity under batch MSR conditions is highest for Cu2In, corroborating the results of a Cu2In/In2O3 sample accessed through reactive metal–support interaction. Under flow MSR operation, Cu7In3 displays considerable deactivation, while Cu2In and Cu11In9 feature stable performance at simultaneously high CO2 selectivity. The missing significant self-activation is most evident in the operando thermogravimetric experiments, where no oxidation is detected for any of the intermetallic compounds. In situ X-ray diffraction allowed us to monitor the partial decomposition and redox activation of the Cu–In intermetallic compounds into Cu0.9In0.1/In2O3 (from Cu7In3), Cu7In3/In2O3 (from Cu2In) and Cu7In3/Cu0.9In0.1/In2O3 (from Cu11In9) interfaces with superior MSR performance compared to the untreated samples. Although the catalytic profiles appear surprisingly similar, the latter interface with the highest indium content exhibits the least deactivation, which we explain by formation of stabilizing In2O3 patches under MSR conditions. To compare the properties of intermetallic compounds and intermetallic compound–oxide interfaces, Cu–In was used as a model to correlate stability limits, self-activation and redox activation with the inherent methanol steam reforming performance.![]()
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Affiliation(s)
- Kevin Ploner
- Department of Physical Chemistry, University of Innsbruck Innrain 52c A-6020 Innsbruck Austria +4351250758003
| | - Andrew Doran
- Advanced Light Source, Lawrence Berkeley National Laboratory Berkeley California 94720 USA
| | - Martin Kunz
- Advanced Light Source, Lawrence Berkeley National Laboratory Berkeley California 94720 USA
| | - Albert Gili
- Chair of Advanced Ceramic Materials, Institut für Werkstoffwissenschaften und - Technologien, Technical University Berlin Hardenbergstr. 40 D-10623 Berlin Germany.,Institute of Chemistry, Technical University Berlin Sekretariat TC 8, Straße des 17. Juni 124 D-10623 Berlin Germany
| | - Aleksander Gurlo
- Chair of Advanced Ceramic Materials, Institut für Werkstoffwissenschaften und - Technologien, Technical University Berlin Hardenbergstr. 40 D-10623 Berlin Germany
| | - Nicolas Köwitsch
- Institute of Chemistry, Materials for Innovative Energy Concepts, Technical University Chemnitz Straße der Nationen 62 D-09111 Chemnitz Germany
| | - Marc Armbrüster
- Institute of Chemistry, Materials for Innovative Energy Concepts, Technical University Chemnitz Straße der Nationen 62 D-09111 Chemnitz Germany
| | - Johannes Bernardi
- University Service Centre for Transmission Electron Microscopy, TU Wien Wiedner Hauptstr. 8-10 A-1040 Vienna Austria
| | - Maximilian Watschinger
- Department of Physical Chemistry, University of Innsbruck Innrain 52c A-6020 Innsbruck Austria +4351250758003
| | - Simon Penner
- Department of Physical Chemistry, University of Innsbruck Innrain 52c A-6020 Innsbruck Austria +4351250758003
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13
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Suchorski Y, Zeininger J, Buhr S, Raab M, Stöger-Pollach M, Bernardi J, Grönbeck H, Rupprechter G. Resolving multifrequential oscillations and nanoscale interfacet communication in single-particle catalysis. Science 2021; 372:1314-1318. [PMID: 34016741 DOI: 10.1126/science.abf8107] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 02/17/2021] [Accepted: 05/05/2021] [Indexed: 11/02/2022]
Abstract
In heterogeneous catalysis research, the reactivity of individual nanofacets of single particles is typically not resolved. We applied in situ field electron microscopy to the apex of a curved rhodium crystal (radius of 650 nanometers), providing high spatial (~2 nanometers) and time resolution (~2 milliseconds) of oscillatory catalytic hydrogen oxidation, to image adsorbed species and reaction fronts on the individual facets. Using ionized water as the imaging species, the active sites were directly imaged with field ion microscopy. The catalytic behavior of differently structured nanofacets and the extent of coupling between them were monitored individually. We observed limited interfacet coupling, entrainment, frequency locking, and reconstruction-induced collapse of spatial coupling. The experimental results are backed up by microkinetic modeling of time-dependent oxygen species coverages and oscillation frequencies.
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Affiliation(s)
- Y Suchorski
- Institute of Materials Chemistry, TU Wien, Getreidemarkt 9, 1060 Vienna, Austria
| | - J Zeininger
- Institute of Materials Chemistry, TU Wien, Getreidemarkt 9, 1060 Vienna, Austria
| | - S Buhr
- Institute of Materials Chemistry, TU Wien, Getreidemarkt 9, 1060 Vienna, Austria
| | - M Raab
- Institute of Materials Chemistry, TU Wien, Getreidemarkt 9, 1060 Vienna, Austria
| | - M Stöger-Pollach
- University Service Center for Transmission Electron Microscopy, TU Wien, Wiedner Hauptstraße 8-10, 1040 Vienna, Austria
| | - J Bernardi
- University Service Center for Transmission Electron Microscopy, TU Wien, Wiedner Hauptstraße 8-10, 1040 Vienna, Austria
| | - H Grönbeck
- Department of Physics and Competence Centre for Catalysis, Chalmers University of Technology, 41296 Göteborg, Sweden
| | - G Rupprechter
- Institute of Materials Chemistry, TU Wien, Getreidemarkt 9, 1060 Vienna, Austria.
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14
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Bekheet MF, Delir Kheyrollahi Nezhad P, Bonmassar N, Schlicker L, Gili A, Praetz S, Gurlo A, Doran A, Gao Y, Heggen M, Niaei A, Farzi A, Schwarz S, Bernardi J, Klötzer B, Penner S. Steering the Methane Dry Reforming Reactivity of Ni/La 2O 3 Catalysts by Controlled In Situ Decomposition of Doped La 2NiO 4 Precursor Structures. ACS Catal 2021; 11:43-59. [PMID: 33425477 PMCID: PMC7783868 DOI: 10.1021/acscatal.0c04290] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Indexed: 11/28/2022]
Abstract
The influence of A- and/or B-site doping of Ruddlesden-Popper perovskite materials on the crystal structure, stability, and dry reforming of methane (DRM) reactivity of specific A2BO4 phases (A = La, Ba; B = Cu, Ni) has been evaluated by a combination of catalytic experiments, in situ X-ray diffraction, X-ray absorption spectroscopy (XAS), X-ray photoelectron spectroscopy (XPS), and aberration-corrected electron microscopy. At room temperature, B-site doping of La2NiO4 with Cu stabilizes the orthorhombic structure (Fmmm) of the perovskite, while A-site doping with Ba yields a tetragonal space group (I4/mmm). We observed the orthorhombic-to-tetragonal transformation above 170 °C for La2Ni0.9Cu0.1O4 and La2Ni0.8Cu0.2O4, slightly higher than for undoped La2NiO4. Loss of oxygen in interstitial sites of the tetragonal structure causes further structure transformations for all samples before decomposition in the temperature range of 400 °C-600 °C. Controlled in situ decomposition of the parent or A/B-site doped perovskite structures in a DRM mixture (CH4:CO2 = 1:1) in all cases yields an active phase consisting of exsolved nanocrystalline metallic Ni particles in contact with hexagonal La2O3 and a mixture of (oxy)carbonate phases (hexagonal and monoclinic La2O2CO3, BaCO3). Differences in the catalytic activity evolve because of (i) the in situ formation of Ni-Cu alloy phases (in a composition of >7:1 = Ni:Cu) for La2Ni0.9Cu0.1O4, La2Ni0.8Cu0.2O4, and La1.8Ba0.2Ni0.9Cu0.1O4, (ii) the resulting Ni particle size and amount of exsolved Ni, and (iii) the inherently different reactivity of the present (oxy)carbonate species. Based on the onset temperature of catalytic DRM activity, the latter decreases in the order of La2Ni0.9Cu0.1O4 ∼ La2Ni0.8Cu0.2O4 ≥ La1.8Ba0.2Ni0.9Cu0.1O4 > La2NiO4 > La1.8Ba0.2NiO4. Simple A-site doped La1.8Ba0.2NiO4 is essentially DRM inactive. The Ni particle size can be efficiently influenced by introducing Ba into the A site of the respective Ruddlesden-Popper structures, allowing us to control the Ni particle size between 10 nm and 30 nm both for simple B-site and A-site doped structures. Hence, it is possible to steer both the extent of the metal-oxide-(oxy)carbonate interface and its chemical composition and reactivity. Counteracting the limitation of the larger Ni particle size, the activity can, however, be improved by additional Cu-doping on the B-site, enhancing the carbon reactivity. Exemplified for the La2NiO4 based systems, we show how the delicate antagonistic balance of doping with Cu (rendering the La2NiO4 structure less stable and suppressing coking by efficiently removing surface carbon) and Ba (rendering the La2NiO4 structure more stable and forming unreactive surface or interfacial carbonates) can be used to tailor prospective DRM-active catalysts.
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Affiliation(s)
- Maged F. Bekheet
- Fachgebiet Keramische
Werkstoffe/Chair of Advanced Ceramic Materials, Institut für
Werkstoffwissenschaften und -technologien, Technische Universität Berlin, Hardenbergstr. 40, 10623 Berlin, Germany
| | - Parastoo Delir Kheyrollahi Nezhad
- Reactor & Catalyst Research Lab, Department of Chemical Engineering, University of Tabriz, Tabriz 51386, Iran
- Department of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
| | - Nicolas Bonmassar
- Department of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
| | - Lukas Schlicker
- Fachgebiet Keramische
Werkstoffe/Chair of Advanced Ceramic Materials, Institut für
Werkstoffwissenschaften und -technologien, Technische Universität Berlin, Hardenbergstr. 40, 10623 Berlin, Germany
| | - Albert Gili
- Fachgebiet Keramische
Werkstoffe/Chair of Advanced Ceramic Materials, Institut für
Werkstoffwissenschaften und -technologien, Technische Universität Berlin, Hardenbergstr. 40, 10623 Berlin, Germany
| | - Sebastian Praetz
- Institute of Optics
and Atomic Physics, Technische Universität
Berlin, Hardenbergstraße
36, 10623 Berlin, Germany
| | - Aleksander Gurlo
- Fachgebiet Keramische
Werkstoffe/Chair of Advanced Ceramic Materials, Institut für
Werkstoffwissenschaften und -technologien, Technische Universität Berlin, Hardenbergstr. 40, 10623 Berlin, Germany
| | - Andrew Doran
- Advanced Light Source, Lawrence Berkeley National Laboratory Berkeley, California 94720, United States
| | - Yuanxu Gao
- Ernst Ruska-Centrum
für Mikroskopie und Spektroskopie mit Elektronen Forschungszentrum
Jülich GmbH 52425 Jülich, Germany
| | - Marc Heggen
- Ernst Ruska-Centrum
für Mikroskopie und Spektroskopie mit Elektronen Forschungszentrum
Jülich GmbH 52425 Jülich, Germany
| | - Aligholi Niaei
- Reactor & Catalyst Research Lab, Department of Chemical Engineering, University of Tabriz, Tabriz 51386, Iran
| | - Ali Farzi
- Reactor & Catalyst Research Lab, Department of Chemical Engineering, University of Tabriz, Tabriz 51386, Iran
| | - Sabine Schwarz
- University Service Center for Transmission Electron Microscopy, TU Wien, Wiedner Hauptstrasse 8-10, A-1040 Vienna, Austria
| | - Johannes Bernardi
- University Service Center for Transmission Electron Microscopy, TU Wien, Wiedner Hauptstrasse 8-10, A-1040 Vienna, Austria
| | - Bernhard Klötzer
- Department of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
| | - Simon Penner
- Department of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
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15
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Capra M, Loria F, Bernini C, Bovone G, Moros A, Stöger-Pollach M, Schachinger T, Bernardi J, Siri AS, Vignolo M. Method for the production of pure and C-doped nanoboron powders tailored for superconductive applications. Nanotechnology 2020; 31:494001. [PMID: 32990260 DOI: 10.1088/1361-6528/abb269] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The present paper describes the improvement of the performances of boron powder obtained applying the freeze-drying process (FDP) for the nanostructuration and doping of B2O3, which is here used as boron precursor. After the nanostructuration process, B2O3 is reduced to elemental nanoboron (nB) through magnesiothermic reaction with Mg. For this work, the usefulness of the process was tested focusing on the carbon-doping (C-doping), using Cblack, inulin and haemoglobin as C sources. The choice of these molecules, their concentration, size and shape, aims at producing improvements in the final compound of boron: in this case the superconductive magnesium diboride, which has been prepared and characterized both as powder and wire. The characteristics of B2O3, B and MgB2 powder, as well as MgB2 wire were tested and compared with that obtained using the best commercial precursors: H. C. Starck micrometric boron and Pavezyum nanometric boron. Both the FDP and the magnesiothermic reaction were carried out with simplicity and a great variety of doping sources, i.e. elements or compounds, which can be organic or inorganic and soluble or insoluble. The FDP allows to produce nB suitable for numerous applications. This process is also very competitive in terms of scalability and production costs if compared to the via gas technique adopted by nanoboron producers currently available on the world market.
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Affiliation(s)
- Marco Capra
- CNR-SPIN, C.so M.F. Perrone 24, 16152 Genova, Italy
- Physic Department of Genoa University, Via Dodecaneso 33, 16146 Genova, Italy
| | | | | | - Gianmarco Bovone
- CNR-SPIN, C.so M.F. Perrone 24, 16152 Genova, Italy
- Now at Department of Quantum Matter Physics (DQMP), University of Geneva, Geneva, Switzerland
| | - Alice Moros
- USTEM - Technische Universitaet Wien, Wien, Wiedner Hauptstr. 8-10, A-1040, Österreich
| | | | - Thomas Schachinger
- USTEM - Technische Universitaet Wien, Wien, Wiedner Hauptstr. 8-10, A-1040, Österreich
| | - Johannes Bernardi
- USTEM - Technische Universitaet Wien, Wien, Wiedner Hauptstr. 8-10, A-1040, Österreich
| | - Antonio Sergio Siri
- Physic Department of Genoa University, Via Dodecaneso 33, 16146 Genova, Italy
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16
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Opitz AK, Nenning A, Vonk V, Volkov S, Bertram F, Summerer H, Schwarz S, Steiger-Thirsfeld A, Bernardi J, Stierle A, Fleig J. Understanding electrochemical switchability of perovskite-type exsolution catalysts. Nat Commun 2020; 11:4801. [PMID: 32968079 PMCID: PMC7511332 DOI: 10.1038/s41467-020-18563-w] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 08/31/2020] [Indexed: 11/09/2022] Open
Abstract
Exsolution of metal nanoparticles from perovskite-type oxides is a very promising approach to obtain catalysts with superior properties. One particularly interesting property of exsolution catalysts is the possibility of electrochemical switching between different activity states. In this work, synchrotron-based in-situ X-ray diffraction experiments on electrochemically polarized La0.6Sr0.4FeO3-δ thin film electrodes are performed, in order to simultaneously obtain insights into the phase composition and the catalytic activity of the electrode surface. This shows that reversible electrochemical switching between a high and low activity state is accompanied by a phase change of exsolved particles between metallic α--Fe and Fe-oxides. Reintegration of iron into the perovskite lattice is thus not required for obtaining a switchable catalyst, making this process especially interesting for intermediate temperature applications. These measurements also reveal how metallic particles on La0.6Sr0.4FeO3-δ electrodes affect the H2 oxidation and H2O splitting mechanism and why the particle size plays a minor role.
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Affiliation(s)
- Alexander K Opitz
- TU Wien, Institute of Chemical Technologies and Analytics, Getreidemarkt 9/164-EC, 1060, Vienna, Austria.
| | - Andreas Nenning
- TU Wien, Institute of Chemical Technologies and Analytics, Getreidemarkt 9/164-EC, 1060, Vienna, Austria
| | - Vedran Vonk
- Deutsches Elektronen-Synchrotron (DESY), 22607, Hamburg, Germany
| | - Sergey Volkov
- Deutsches Elektronen-Synchrotron (DESY), 22607, Hamburg, Germany
| | - Florian Bertram
- Deutsches Elektronen-Synchrotron (DESY), 22607, Hamburg, Germany
| | - Harald Summerer
- TU Wien, Institute of Chemical Technologies and Analytics, Getreidemarkt 9/164-EC, 1060, Vienna, Austria
- TU Wien, Institute of Materials Chemistry, Getreidemarkt 9/165-PC, 1060, Vienna, Austria
| | - Sabine Schwarz
- TU Wien, University Service Centre for Transmission Electron Microscopy (USTEM), Wiedner Hauptstraße 8-10, 1040, Vienna, Austria
| | - Andreas Steiger-Thirsfeld
- TU Wien, University Service Centre for Transmission Electron Microscopy (USTEM), Wiedner Hauptstraße 8-10, 1040, Vienna, Austria
| | - Johannes Bernardi
- TU Wien, University Service Centre for Transmission Electron Microscopy (USTEM), Wiedner Hauptstraße 8-10, 1040, Vienna, Austria
| | - Andreas Stierle
- Deutsches Elektronen-Synchrotron (DESY), 22607, Hamburg, Germany
| | - Jürgen Fleig
- TU Wien, Institute of Chemical Technologies and Analytics, Getreidemarkt 9/164-EC, 1060, Vienna, Austria
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17
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Altrocchi C, de Korte T, Braam S, Volders P, Bernardi J, Spatjens R, Zaza A, Heijman J. Repolarization instability and arrhythmia susceptibility upon IKr block in isolated and 2D-monolayers of hiPSC-CMs. J Pharmacol Toxicol Methods 2020. [DOI: 10.1016/j.vascn.2020.106723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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18
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Yan X, Bauer E, Rogl P, Bernardi J, Prokofiev A, Paschen S. Thermoelectric Properties and Stability of Nanocomposites Type I Clathrate Ba‐Cu‐Si with SiC. Z Anorg Allg Chem 2020. [DOI: 10.1002/zaac.202000043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Xinlin Yan
- Institute of Solid State Physics Vienna University of Technology Wiedner Hauptstr. 8–10 1040 Vienna Austria
| | - Ernst Bauer
- Institute of Solid State Physics Vienna University of Technology Wiedner Hauptstr. 8–10 1040 Vienna Austria
| | - Peter Rogl
- Institute of Materials Chemistry and Research Vienna University Währingerstr. 42 1090 Vienna Austria
| | | | - Andrey Prokofiev
- Institute of Solid State Physics Vienna University of Technology Wiedner Hauptstr. 8–10 1040 Vienna Austria
| | - Silke Paschen
- Institute of Solid State Physics Vienna University of Technology Wiedner Hauptstr. 8–10 1040 Vienna Austria
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19
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Nedelkovski V, Hahn R, Mayrhofer PH, Steiger-Thirsfeld A, Bernardi J, Thurner PJ. Influence of experimental constraints on micromechanical assessment of micromachined hard-tissue samples. J Mech Behav Biomed Mater 2020; 106:103741. [PMID: 32250952 DOI: 10.1016/j.jmbbm.2020.103741] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 02/14/2020] [Accepted: 03/10/2020] [Indexed: 11/26/2022]
Abstract
Continuing technological advancement of mechanical characterization at the microscale has enabled the isolation of micron-sized specimens and their direct mechanical characterization. Such techniques, initially developed for engineering materials and MEMS, can also be applied on hard biological materials. Bone is a material with a complex hierarchical structure ranging from the macro- all the way down to the nanoscale. To fully understand bone tissue mechanics, knowledge of the mechanics of all structural elements i.e. at every length scale is necessary. Particularly, the mechanical properties of microstructural elements, such as bone lamellae are still largely unknown. In the last decade, testing protocols have been devised to close this gap including bending and compression of micrometer-sized bone specimens. However, the precision and accuracy of results obtained have not been discussed. In this study, we aim to do exactly this: we validate microbeam bending by testing silicon microbeams with known mechanical constants, and evaluate the precision and sources of errors in both microbeam bending and micropillar compression by means of finite element (FE) modeling. Bending of Si-microbeams reproduced the expected value for the bending modulus within 17% accuracy, although the effect of geometrical uncertainties was estimated to result in relative errors of up to 50%. The deformation of constraining bulk material had a smaller influence, with relative errors of 11%, for microbeam bending and 25% for micropillar compression. For the latter this error could be sufficiently eliminated by the Sneddon correction. The tapering of micropillars had a negligible effect on overall apparent stiffness, but induced inhomogeneous stress state within micropillars may lead to superposed structural deformation mechanisms and be responsible for failure patterns observed in past studies.
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Affiliation(s)
- Vedran Nedelkovski
- Institute of Lightweight Design and Structural Biomechanics, TU Wien, 1060, Vienna, Austria
| | - Rainer Hahn
- Institute of Materials Science and Technology, TU Wien, 1060, Vienna, Austria
| | - Paul H Mayrhofer
- Institute of Materials Science and Technology, TU Wien, 1060, Vienna, Austria
| | | | - Johannes Bernardi
- University Service Center for Transmission Electron Microscopy, TU Wien, 1040, Vienna, Austria
| | - Philipp J Thurner
- Institute of Lightweight Design and Structural Biomechanics, TU Wien, 1060, Vienna, Austria.
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20
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Bonmassar N, Bekheet MF, Schlicker L, Gili A, Gurlo A, Doran A, Gao Y, Heggen M, Bernardi J, Klötzer B, Penner S. In Situ-Determined Catalytically Active State of LaNiO3 in Methane Dry Reforming. ACS Catal 2019. [DOI: 10.1021/acscatal.9b03687] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Nicolas Bonmassar
- Department of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
| | - Maged F. Bekheet
- Fachgebiet Keramische Werkstoffe/Chair of Advanced Ceramic Materials, Institut für Werkstoffwissenschaften und -technologien, Technische Universität Berlin, Hardenbergstr. 40, 10623 Berlin, Germany
| | - Lukas Schlicker
- Fachgebiet Keramische Werkstoffe/Chair of Advanced Ceramic Materials, Institut für Werkstoffwissenschaften und -technologien, Technische Universität Berlin, Hardenbergstr. 40, 10623 Berlin, Germany
| | - Albert Gili
- Fachgebiet Keramische Werkstoffe/Chair of Advanced Ceramic Materials, Institut für Werkstoffwissenschaften und -technologien, Technische Universität Berlin, Hardenbergstr. 40, 10623 Berlin, Germany
| | - Aleksander Gurlo
- Fachgebiet Keramische Werkstoffe/Chair of Advanced Ceramic Materials, Institut für Werkstoffwissenschaften und -technologien, Technische Universität Berlin, Hardenbergstr. 40, 10623 Berlin, Germany
| | - Andrew Doran
- Advanced Light Source, Lawrence Berkeley National Laboratory Berkeley, California 94720, United States
| | - Yuanxu Gao
- Ernst Ruska-Centrum für Mikroskopie und Spektroskopie mit Elektronen, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Marc Heggen
- Ernst Ruska-Centrum für Mikroskopie und Spektroskopie mit Elektronen, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Johannes Bernardi
- University Service Center for Transmission Electron Microscopy, TU Wien, Wiedner Hauptstrasse 8-10, A-1040 Vienna, Austria
| | - Bernhard Klötzer
- Department of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
| | - Simon Penner
- Department of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
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21
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Grünbacher M, Tarjomannejad A, Nezhad PDK, Praty C, Ploner K, Mohammadi A, Niaei A, Klötzer B, Schwarz S, Bernardi J, Farzi A, Gómez MJI, Rivero VT, Penner S. Promotion of La(Cu0.7Mn0.3)0.98M0.02O3−δ (M = Pd, Pt, Ru and Rh) perovskite catalysts by noble metals for the reduction of NO by CO. J Catal 2019. [DOI: 10.1016/j.jcat.2019.09.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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22
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Lukashuk L, Yigit N, Li H, Bernardi J, Föttinger K, Rupprechter G. Operando XAS and NAP-XPS investigation of CO oxidation on meso- and nanoscale CoO catalysts. Catal Today 2019. [DOI: 10.1016/j.cattod.2018.12.052] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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23
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Seifner MS, Dijkstra A, Bernardi J, Steiger-Thirsfeld A, Sistani M, Lugstein A, Haverkort JEM, Barth S. Epitaxial Ge 0.81Sn 0.19 Nanowires for Nanoscale Mid-Infrared Emitters. ACS Nano 2019; 13:8047-8054. [PMID: 31282653 DOI: 10.1021/acsnano.9b02843] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Highly oriented Ge0.81Sn0.19 nanowires have been synthesized by a low-temperature chemical vapor deposition growth technique. The nanostructures form by a self-seeded vapor-liquid-solid mechanism. In this process, liquid metallic Sn seeds enable the anisotropic crystal growth and act as a sole source of Sn for the formation of the metastable Ge1-xSnx semiconductor material. The strain relaxation for a lattice mismatch of ε = 2.94% between the Ge (111) substrate and the constant Ge0.81Sn0.19 composition of nanowires is confined to a transition zone of <100 nm. In contrast, Ge1-xSnx structures with diameters in the micrometer range show a 5-fold longer compositional gradient very similar to epitaxial thin-film growth. Effects of the Sn growth promoters' dimensions on the morphological and compositional evolution of Ge1-xSnx are described. The temperature- and laser power-dependent photoluminescence analyses verify the formation of a direct band gap material with emission in the mid-infrared region and values expected for unstrained Ge0.81Sn0.19 (e.g., band gap of 0.3 eV at room temperature). These materials hold promise in applications such as thermal imaging and photodetection as well as building blocks for group IV-based mid- to near-IR photonics.
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Affiliation(s)
- Michael S Seifner
- Institute of Materials Chemistry , TU Wien , Getreidemarkt 9/BC/02 , A-1060 Vienna , Austria
| | - Alain Dijkstra
- Department of Applied Physics , Eindhoven University of Technology , 5600MB Eindhoven , The Netherlands
| | - Johannes Bernardi
- University Service Center for TEM (USTEM) , TU Wien , Wiedner Hauptstraße 8-10 , 1040 Vienna , Austria
| | - Andreas Steiger-Thirsfeld
- University Service Center for TEM (USTEM) , TU Wien , Wiedner Hauptstraße 8-10 , 1040 Vienna , Austria
| | - Masiar Sistani
- Institute of Solid State Electronics , TU Wien , Gußhausstraße 25-25a , 1040 Vienna , Austria
| | - Alois Lugstein
- Institute of Solid State Electronics , TU Wien , Gußhausstraße 25-25a , 1040 Vienna , Austria
| | - Jos E M Haverkort
- Department of Applied Physics , Eindhoven University of Technology , 5600MB Eindhoven , The Netherlands
| | - Sven Barth
- Institute of Materials Chemistry , TU Wien , Getreidemarkt 9/BC/02 , A-1060 Vienna , Austria
- Physikalisches Institut , Goethe-Universität Frankfurt , Max-von-Laue-Straße 1 , 60438 Frankfurt am Main , Germany
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24
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Kocsis K, Niedermaier M, Kasparek V, Bernardi J, Redhammer G, Bockstedte M, Berger T, Diwald O. From Anhydrous Zinc Oxide Nanoparticle Powders to Aqueous Colloids: Impact of Water Condensation and Organic Salt Adsorption on Free Exciton Emission. Langmuir 2019; 35:8741-8747. [PMID: 31244249 PMCID: PMC7116045 DOI: 10.1021/acs.langmuir.9b00656] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Variations in the composition and structure of ZnO nanoparticle interfaces have a key influence on the materials' optoelectronic properties and are responsible for high number of discrepant results reported for ZnO-based nanomaterials. Here, we conduct a systematic study of the room-temperature photoluminescence of anhydrous ZnO nanocrystals, as synthesized in the gas phase and processed in water-free atmosphere, and of their colloidal derivatives in aqueous dispersions with varying amounts of organic salt admixtures. A free exciton band at hν = 3.3 eV is essentially absent in the anhydrous ZnO nanocrystal powders measured in vacuum or in oxygen atmosphere. Surface hydration of the nanoparticles during colloid formation leads to the emergence of the free exciton band at hν = 3.3 eV and induces a small but significant release in lattice strain as detected by X-ray diffraction. Most importantly, admixture of acetate or citrate ions to the aqueous colloidal dispersions not only allows for the control of the ζ-potential but also affects the intensity of the free exciton emission in a correlated manner. The buildup of negative charge at the solid-liquid interface, as produced by citrate adsorption, increases the free exciton emission. This effect is attributed to the suppression of electron trapping in the near-surface region, which counteracts nonradiative exciton recombination. Using well-defined ZnO nanoparticles as model systems for interface chemistry studies, our findings highlight water-induced key effects that depend on the composition of the aqueous solution shell around the semiconducting metal oxide nanoparticles.
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Affiliation(s)
- Krisztina Kocsis
- Department of Chemistry and Physics of Materials, University
of Salzburg, Jakob-Haringer-Strasse 2a, 5020 Salzburg, Austria
| | - Matthias Niedermaier
- Department of Chemistry and Physics of Materials, University
of Salzburg, Jakob-Haringer-Strasse 2a, 5020 Salzburg, Austria
| | - Vít Kasparek
- Central European Institute of Technology, Brno University of
Technology, Purkynova 123, 612 00 Brno, Czech Republic
| | - Johannes Bernardi
- University Service Centre for Transmission Electron
Microscopy, Technische Universität Wien, 1040 Vienna, Austria
| | - Günther Redhammer
- Department of Chemistry and Physics of Materials, University
of Salzburg, Jakob-Haringer-Strasse 2a, 5020 Salzburg, Austria
| | - Michel Bockstedte
- Department of Chemistry and Physics of Materials, University
of Salzburg, Jakob-Haringer-Strasse 2a, 5020 Salzburg, Austria
| | - Thomas Berger
- Department of Chemistry and Physics of Materials, University
of Salzburg, Jakob-Haringer-Strasse 2a, 5020 Salzburg, Austria
| | - Oliver Diwald
- Department of Chemistry and Physics of Materials, University
of Salzburg, Jakob-Haringer-Strasse 2a, 5020 Salzburg, Austria
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25
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Niedermaier M, Taniteerawong C, Schwab T, Zickler G, Bernardi J, Diwald O. Impurity Segregation and Nanoparticle Reorganization of Indium Doped MgO Cubes. ChemNanoMat 2019; 5:634-641. [PMID: 31231606 PMCID: PMC6563704 DOI: 10.1002/cnma.201900077] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Accepted: 02/26/2019] [Indexed: 06/09/2023]
Abstract
Metal oxide nanocomposites are non-equilibrium solids and promising precursors for functional materials. Annealing of such materials can provide control over impurity segregation and, depending on the level of consolidation, represents a versatile approach to engineer free surfaces, particle-particle interfaces and grain boundaries. Starting with indium-magnesium-oxide nanoparticle powders obtained via injection of an indium organic precursor into the magnesium combustion flame and subsequent particle quenching in argon, we investigated the stability of the trivalent In3+ ions in the host lattice of MgO nanoparticles by determining grain growth, morphology evolution and impurity segregation. The latter process is initiated by vacuum annealing at 873 K and can be tracked at 1173 K on a time scale of minutes. In the first instance the surface segregated indium wets the nanoparticle interfaces. After prolonged annealing indium evaporates and leaves the powder via the gas phase. Resulting MgO nanocubes are devoid of residual indium, regain their high morphological definition and show spectroscopic fingerprints (UV Diffuse Reflectance and Photoluminescence emission) that are characteristic of electronically unperturbed MgO cube corner and edge features. The results of this combined XRD, TEM, and spectroscopy study reveal the parameter window within which control over indium segregation is used to introduce a semiconducting metal oxide component into the intergranular region between insulating MgO nanograins.
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Affiliation(s)
- Matthias Niedermaier
- Department of Chemistry and Physics of MaterialsUniversity of SalzburgJakob-Haringer-Strasse 2a5020SalzburgAustria
| | - Chatpawee Taniteerawong
- Department of Chemistry and Physics of MaterialsUniversity of SalzburgJakob-Haringer-Strasse 2a5020SalzburgAustria
| | - Thomas Schwab
- Department of Chemistry and Physics of MaterialsUniversity of SalzburgJakob-Haringer-Strasse 2a5020SalzburgAustria
| | - Gregor Zickler
- Department of Chemistry and Physics of MaterialsUniversity of SalzburgJakob-Haringer-Strasse 2a5020SalzburgAustria
| | - Johannes Bernardi
- University Service Centre for Transmission Electron MicroscopyTechnische Universität Wien1040ViennaAustria
| | - Oliver Diwald
- Department of Chemistry and Physics of MaterialsUniversity of SalzburgJakob-Haringer-Strasse 2a5020SalzburgAustria
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26
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Ploner K, Schlicker L, Gili A, Gurlo A, Doran A, Zhang L, Armbrüster M, Obendorf D, Bernardi J, Klötzer B, Penner S. Reactive metal-support interaction in the Cu-In 2O 3 system: intermetallic compound formation and its consequences for CO 2-selective methanol steam reforming. Sci Technol Adv Mater 2019; 20:356-366. [PMID: 31068984 PMCID: PMC6493314 DOI: 10.1080/14686996.2019.1590127] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 02/27/2019] [Accepted: 02/28/2019] [Indexed: 06/09/2023]
Abstract
The reactive metal-support interaction in the Cu-In2O3 system and its implications on the CO2 selectivity in methanol steam reforming (MSR) have been assessed using nanosized Cu particles on a powdered cubic In2O3 support. Reduction in hydrogen at 300 °C resulted in the formation of metallic Cu particles on In2O3. This system already represents a highly CO2-selective MSR catalyst with ~93% selectivity, but only 56% methanol conversion and a maximum H2 formation rate of 1.3 µmol gCu -1 s-1. After reduction at 400 °C, the system enters an In2O3-supported intermetallic compound state with Cu2In as the majority phase. Cu2In exhibits markedly different self-activating properties at equally pronounced CO2 selectivities between 92% and 94%. A methanol conversion improvement from roughly 64% to 84% accompanied by an increase in the maximum hydrogen formation rate from 1.8 to 3.8 µmol gCu -1 s-1 has been observed from the first to the fourth consecutive runs. The presented results directly show the prospective properties of a new class of Cu-based intermetallic materials, beneficially combining the MSR properties of the catalyst's constituents Cu and In2O3. In essence, the results also open up the pathway to in-depth development of potentially CO2-selective bulk intermetallic Cu-In compounds with well-defined stoichiometry in MSR.
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Affiliation(s)
- Kevin Ploner
- Department of Physical Chemistry, University of Innsbruck, Innsbruck, Austria
| | - Lukas Schlicker
- Fachgebiet Keramische Werkstoffe/Chair of Advanced Ceramic Materials, Institut für Werkstoffwissenschaften und -technologien, Berlin, Germany
| | - Albert Gili
- Fachgebiet Keramische Werkstoffe/Chair of Advanced Ceramic Materials, Institut für Werkstoffwissenschaften und -technologien, Berlin, Germany
| | - Aleksander Gurlo
- Fachgebiet Keramische Werkstoffe/Chair of Advanced Ceramic Materials, Institut für Werkstoffwissenschaften und -technologien, Berlin, Germany
| | - Andrew Doran
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Lei Zhang
- Faculty of Natural Sciences, Institute of Chemistry, Materials for Innovative Energy Concepts, Chemnitz University of Technology, Chemnitz, Germany
| | - Marc Armbrüster
- Faculty of Natural Sciences, Institute of Chemistry, Materials for Innovative Energy Concepts, Chemnitz University of Technology, Chemnitz, Germany
| | - Dagmar Obendorf
- Institut für Analytische Chemie und Radiochemie, University of Innsbruck, Innsbruck, Austria
| | - Johannes Bernardi
- University Service Center for Transmission Electron Microscopy, Vienna, Austria
| | - Bernhard Klötzer
- Department of Physical Chemistry, University of Innsbruck, Innsbruck, Austria
| | - Simon Penner
- Department of Physical Chemistry, University of Innsbruck, Innsbruck, Austria
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27
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Suchorski Y, Datler M, Bespalov I, Zeininger J, Stöger-Pollach M, Bernardi J, Grönbeck H, Rupprechter G. Surface-Structure Libraries: Multifrequential Oscillations in Catalytic Hydrogen Oxidation on Rhodium. J Phys Chem C Nanomater Interfaces 2019; 123:4217-4227. [PMID: 31057690 PMCID: PMC6494118 DOI: 10.1021/acs.jpcc.8b11421] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 01/18/2019] [Indexed: 05/18/2023]
Abstract
Multifrequential oscillating spatiotemporal patterns in the catalytic hydrogen oxidation on rhodium have been observed in situ in the 10-6 mbar pressure range using photoemission electron microscopy. The effect is manifested by periodic chemical waves, which travel over the polycrystalline Rh surface and change their oscillation frequency while crossing boundaries between different Rh(hkl) domains. Each crystallographically specific μm-sized Rh(hkl) domain exhibits an individual wave pattern and oscillation frequency, despite the global diffusional coupling of the surface reaction, altogether creating a structure library. This unique reaction behavior is attributed to the ability of stepped surfaces of high-Miller-index domains to facilitate the formation of subsurface oxygen, serving as a feedback mechanism of kinetic oscillations. Formation of a network of subsurface oxygen as a result of colliding reaction fronts was observed in situ. Microkinetic model analysis was used to rationalize the observed effects and to reveal the relation between the barriers for surface oxidation and oscillation frequency. Structural limits of the oscillations, the existence range of oscillations, as well as the effect of varying hydrogen pressure are demonstrated.
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Affiliation(s)
- Yuri Suchorski
- Institute
of Materials Chemistry, Technische Universität
Wien, Getreidemarkt 9, 1060 Vienna, Austria
| | - Martin Datler
- Institute
of Materials Chemistry, Technische Universität
Wien, Getreidemarkt 9, 1060 Vienna, Austria
| | - Ivan Bespalov
- Institute
of Materials Chemistry, Technische Universität
Wien, Getreidemarkt 9, 1060 Vienna, Austria
| | - Johannes Zeininger
- Institute
of Materials Chemistry, Technische Universität
Wien, Getreidemarkt 9, 1060 Vienna, Austria
| | | | - Johannes Bernardi
- USTEM, Technische Universität Wien, Wiedner Hauptstrasse 8-10, 1040 Vienna, Austria
| | - Henrik Grönbeck
- Department
of Physics and Competence Centre for Catalysis, Chalmers University of Technology, 41296 Gothenburg, Sweden
| | - Günther Rupprechter
- Institute
of Materials Chemistry, Technische Universität
Wien, Getreidemarkt 9, 1060 Vienna, Austria
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28
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Hauser D, Auer A, Kunze-Liebhäuser J, Schwarz S, Bernardi J, Penner S. Hybrid synthesis of zirconium oxycarbide nanopowders with defined and controlled composition. RSC Adv 2019; 9:3151-3156. [PMID: 30931107 PMCID: PMC6394884 DOI: 10.1039/c8ra09584a] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Accepted: 01/17/2019] [Indexed: 01/17/2023] Open
Abstract
A combined synthesis strategy involving a carbothermal reduction and gelation approach with glycine as gelating agent was used to obtain Zr-based (oxy)carbide materials with defined and controlled composition. A comparatively low temperature approach (1500 °C) allows exploration of the ZrC–ZrO2 phase diagram and reproducibly leads to zirconium (oxy)carbide phases with different C/Zr ratios, as confirmed by combined X-ray diffraction (XRD) and transmission electron microscopy (TEM) data. The latter also indicates a chemically very homogeneous distribution of oxygen and carbon throughout the sample bulk, a prerequisite for further characterization of its intrinsic physico-chemical properties. Due to the general variability of the synthesis procedure – variation of metal precursor, amount of gelating agent and carbon precursor source – it is expected that the method can be easily adapted and transferred to other metal – oxycarbide materials. A combined synthesis strategy involving a carbothermal reduction and gelation approach with glycine as gelating agent was used to obtain Zr-based (oxy)carbide materials with defined and controlled composition.![]()
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Affiliation(s)
- Daniel Hauser
- Institute of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria. ; Tel: +43 512 507 58003
| | - Andrea Auer
- Institute of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria. ; Tel: +43 512 507 58003
| | - Julia Kunze-Liebhäuser
- Institute of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria. ; Tel: +43 512 507 58003
| | - Sabine Schwarz
- University Service Centre for Transmission Electron Microscopy, Technische Universität Wien, Wiedner Hauptstrasse 4-6, A-1040 Wien, Austria
| | - Johannes Bernardi
- University Service Centre for Transmission Electron Microscopy, Technische Universität Wien, Wiedner Hauptstrasse 4-6, A-1040 Wien, Austria
| | - Simon Penner
- Institute of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria. ; Tel: +43 512 507 58003
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29
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Götsch T, Köpfle N, Grünbacher M, Bernardi J, Carbonio EA, Hävecker M, Knop-Gericke A, Bekheet MF, Schlicker L, Doran A, Gurlo A, Franz A, Klötzer B, Penner S. Crystallographic and electronic evolution of lanthanum strontium ferrite (La0.6Sr0.4FeO3−δ) thin film and bulk model systems during iron exsolution. Phys Chem Chem Phys 2019; 21:3781-3794. [DOI: 10.1039/c8cp07743f] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We study the changes in the crystallographic phases and in the chemical states during the iron exsolution process of lanthanum strontium ferrite (LSF, La0.6Sr0.4FeO3−δ).
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30
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Thomele D, Gheisi AR, Niedermaier M, Elsässer MS, Bernardi J, Grönbeck H, Diwald O. Thin water films and particle morphology evolution in nanocrystalline MgO. J Am Ceram Soc 2018; 101:4994-5003. [PMID: 30333631 PMCID: PMC6175089 DOI: 10.1111/jace.15775] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 05/05/2018] [Indexed: 05/29/2023]
Abstract
A key question in the field of ceramics and catalysis is how and to what extent residual water in the reactive environment of a metal oxide particle powder affects particle coarsening and morphology. With X-ray Diffraction (XRD) and Transmission Electron Microscopy (TEM), we investigated annealing-induced morphology changes on powders of MgO nanocubes in different gaseous H2O environments. The use of such a model system for particle powders enabled us to describe how adsorbed water that originates from short exposure to air determines the evolution of MgO grain size, morphology, and microstructure. While cubic nanoparticles with a predominant abundance of (100) surface planes retain their shape after annealing to T = 1173 K under continuous pumping with a base pressure of water p(H2O) = 10-5 mbar, higher water partial pressures promote mass transport on the surfaces and across interfaces of such particle systems. This leads to substantial growth and intergrowth of particles and simultaneously favors the formation of step edges and shallow protrusions on terraces. The mass transfer is promoted by thin films of water providing a two-dimensional solvent for Mg2+ ion hydration. In addition, we obtained direct evidence for hydroxylation-induced stabilization of (110) faces and step edges of the grain surfaces.
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Affiliation(s)
- Daniel Thomele
- Department of Chemistry and Physics of MaterialsParis‐Lodron University SalzburgSalzburgAustria
| | - Amir R. Gheisi
- Institute of Particle TechnologyFriedrich‐Alexander Universität Erlangen‐NürnbergErlangenGermany
| | - Matthias Niedermaier
- Department of Chemistry and Physics of MaterialsParis‐Lodron University SalzburgSalzburgAustria
| | - Michael S. Elsässer
- Department of Chemistry and Physics of MaterialsParis‐Lodron University SalzburgSalzburgAustria
| | - Johannes Bernardi
- University Service Center for Transmission Electron MicroscopyTechnische Universität WienViennaAustria
| | - Henrik Grönbeck
- Department of Physics and Competence Centre for CatalysisChalmers University of TechnologyGothenburgSweden
| | - Oliver Diwald
- Department of Chemistry and Physics of MaterialsParis‐Lodron University SalzburgSalzburgAustria
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31
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Götsch T, Ploner K, Bernardi J, Schlicker L, Gili A, Doran A, Gurlo A, Penner S. Formation of Pd-Ce intermetallic compounds by reductive metal-support interaction. J SOLID STATE CHEM 2018. [DOI: 10.1016/j.jssc.2018.05.036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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32
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Suchorski Y, Datler M, Bespalov I, Zeininger J, Stöger-Pollach M, Bernardi J, Grönbeck H, Rupprechter G. Visualizing catalyst heterogeneity by a multifrequential oscillating reaction. Nat Commun 2018; 9:600. [PMID: 29426883 PMCID: PMC5807506 DOI: 10.1038/s41467-018-03007-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 01/12/2018] [Indexed: 11/23/2022] Open
Abstract
It is well documented that different surface structures of catalytically active metals may exhibit different catalytic properties. This is typically examined by comparing the catalytic activities and/or selectivities of various well-defined smooth and stepped/kinked single crystal surfaces. Here we report the direct observation of the heterogeneity of active polycrystalline surfaces under reaction conditions, which is manifested by multifrequential oscillations during hydrogen oxidation over rhodium, imaged in situ by photoemission electron microscopy. Each specific surface structure, i.e. the crystallographically different µm-sized domains of rhodium, exhibits an individual spiral pattern and oscillation frequency, despite the global diffusional coupling of the surface reaction. This reaction behavior is attributed to the ability of stepped surfaces of high-Miller-index domains to facilitate the formation of subsurface oxygen, serving as feedback mechanism of the observed oscillations. The current experimental findings, backed by microkinetic modeling, may open an alternative approach towards addressing the structure-sensitivity of heterogeneous surfaces.
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Affiliation(s)
- Yuri Suchorski
- Institute of Materials Chemistry, Technische Universität Wien, 1060, Vienna, Austria
| | - Martin Datler
- Institute of Materials Chemistry, Technische Universität Wien, 1060, Vienna, Austria
| | - Ivan Bespalov
- Institute of Materials Chemistry, Technische Universität Wien, 1060, Vienna, Austria
| | - Johannes Zeininger
- Institute of Materials Chemistry, Technische Universität Wien, 1060, Vienna, Austria
| | | | | | - Henrik Grönbeck
- Department of Physics and Competence Centre for Catalysis, Chalmers University of Technology, SE-412 96, Gothenburg, Sweden
| | - Günther Rupprechter
- Institute of Materials Chemistry, Technische Universität Wien, 1060, Vienna, Austria.
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33
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Yakymovych A, Kaptay G, Flandorfer H, Bernardi J, Schwarz S, Ipser H. The nano heat effect of replacing macro-particles by nano-particles in drop calorimetry: the case of core/shell metal/oxide nano-particles. RSC Adv 2018; 8:8856-8869. [PMID: 35539825 PMCID: PMC9078637 DOI: 10.1039/c7ra13643a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2017] [Accepted: 02/20/2018] [Indexed: 11/21/2022] Open
Abstract
Difference in the enthalpy effect by replacing micro- by nano-sized particles in drop calorimetry.
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Affiliation(s)
- A. Yakymovych
- Department of Inorganic Chemistry – Functional Materials
- Faculty of Chemistry
- University of Vienna
- 1090 Vienna
- Austria
| | - G. Kaptay
- Department of Nanotechnology
- University of Miskolc
- Miskolc-Egyetemváros
- Hungary-3515
- MTA-ME Materials Science Research Group
| | - H. Flandorfer
- Department of Inorganic Chemistry – Functional Materials
- Faculty of Chemistry
- University of Vienna
- 1090 Vienna
- Austria
| | - J. Bernardi
- University Service Center for Transmission Electron Microscopy
- Vienna University of Technology
- A-1040 Vienna
- Austria
| | - S. Schwarz
- University Service Center for Transmission Electron Microscopy
- Vienna University of Technology
- A-1040 Vienna
- Austria
| | - H. Ipser
- Department of Inorganic Chemistry – Functional Materials
- Faculty of Chemistry
- University of Vienna
- 1090 Vienna
- Austria
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34
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Salihovic M, Hüsing N, Bernardi J, Presser V, Elsaesser MS. Carbon aerogels with improved flexibility by sphere templating. RSC Adv 2018; 8:27326-27331. [PMID: 35539967 PMCID: PMC9083318 DOI: 10.1039/c8ra04848g] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 07/24/2018] [Indexed: 11/21/2022] Open
Abstract
Using soft templating, mechanically reversible compressible resorcinol–formaldehyde aerogels can be converted into mechanically reversible compressible carbon aerogels with high surface area by carbonization in an inert atmosphere.
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Affiliation(s)
- Miralem Salihovic
- Chemistry and Physics of Materials
- University of Salzburg
- 5020 Salzburg
- Austria
| | - Nicola Hüsing
- Chemistry and Physics of Materials
- University of Salzburg
- 5020 Salzburg
- Austria
| | | | - Volker Presser
- INM – Leibniz Institute for New Materials
- 66123 Saarbrücken
- Germany
- Saarland University
- 66123 Saarbrücken
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35
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Navickas E, Chen Y, Lu Q, Wallisch W, Huber TM, Bernardi J, Stöger-Pollach M, Friedbacher G, Hutter H, Yildiz B, Fleig J. Dislocations Accelerate Oxygen Ion Diffusion in La 0.8Sr 0.2MnO 3 Epitaxial Thin Films. ACS Nano 2017; 11:11475-11487. [PMID: 28981249 PMCID: PMC5707630 DOI: 10.1021/acsnano.7b06228] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 10/05/2017] [Indexed: 05/24/2023]
Abstract
Revealing whether dislocations accelerate oxygen ion transport is important for providing abilities in tuning the ionic conductivity of ceramic materials. In this study, we report how dislocations affect oxygen ion diffusion in Sr-doped LaMnO3 (LSM), a model perovskite oxide that serves in energy conversion technologies. LSM epitaxial thin films with thicknesses ranging from 10 nm to more than 100 nm were prepared by pulsed laser deposition on single-crystal LaAlO3 and SrTiO3 substrates. The lattice mismatch between the film and substrates induces compressive or tensile in-plane strain in the LSM layers. This lattice strain is partially reduced by dislocations, especially in the LSM films on LaAlO3. Oxygen isotope exchange measured by secondary ion mass spectrometry revealed the existence of at least two very different diffusion coefficients in the LSM films on LaAlO3. The diffusion profiles can be quantitatively explained by the existence of fast oxygen ion diffusion along threading dislocations that is faster by up to 3 orders of magnitude compared to that in LSM bulk.
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Affiliation(s)
- Edvinas Navickas
- Institute
of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9, Vienna A-1060, Austria
| | - Yan Chen
- Department
of Nuclear Science and Engineering and Department of Materials Science and
Engineering, Massachusetts Institute of
Technology, 77 Massachusetts Avenue, 24-107, Cambridge, Massachusetts 02139, United States
| | - Qiyang Lu
- Department
of Nuclear Science and Engineering and Department of Materials Science and
Engineering, Massachusetts Institute of
Technology, 77 Massachusetts Avenue, 24-107, Cambridge, Massachusetts 02139, United States
| | - Wolfgang Wallisch
- University
Service Centre for Transmission Electron Microscopy, Vienna University of Technology, Wiedner Hauptstr. 8-10, Vienna A-1040, Austria
| | - Tobias M. Huber
- Institute
of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9, Vienna A-1060, Austria
- Department
of Nuclear Science and Engineering and Department of Materials Science and
Engineering, Massachusetts Institute of
Technology, 77 Massachusetts Avenue, 24-107, Cambridge, Massachusetts 02139, United States
- Next-Generation
Fuel Cell Research Center (NEXT-FC) and International Institute for Carbon-Neutral
Energy Research (WPI-I2CNER), Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Johannes Bernardi
- University
Service Centre for Transmission Electron Microscopy, Vienna University of Technology, Wiedner Hauptstr. 8-10, Vienna A-1040, Austria
| | - Michael Stöger-Pollach
- University
Service Centre for Transmission Electron Microscopy, Vienna University of Technology, Wiedner Hauptstr. 8-10, Vienna A-1040, Austria
| | - Gernot Friedbacher
- Institute
of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9, Vienna A-1060, Austria
| | - Herbert Hutter
- Institute
of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9, Vienna A-1060, Austria
| | - Bilge Yildiz
- Department
of Nuclear Science and Engineering and Department of Materials Science and
Engineering, Massachusetts Institute of
Technology, 77 Massachusetts Avenue, 24-107, Cambridge, Massachusetts 02139, United States
| | - Jürgen Fleig
- Institute
of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9, Vienna A-1060, Austria
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36
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Ploner K, Götsch T, Kogler G, Thalinger R, Bernardi J, Zhao Q, Zhuo C, Klötzer B, Penner S. Structural and Catalytic Properties of Ag- and Co3O4-Impregnated Strontium Titanium Ferrite SrTi0.7Fe0.3O3−δ in Methanol Steam Reforming. Ind Eng Chem Res 2017. [DOI: 10.1021/acs.iecr.7b03778] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Kevin Ploner
- Institut
für Physikalische Chemie, Universität Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
| | - Thomas Götsch
- Institut
für Physikalische Chemie, Universität Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
| | - Günther Kogler
- Institut
für Physikalische Chemie, Universität Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
| | - Ramona Thalinger
- Institut
für Physikalische Chemie, Universität Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
| | - Johannes Bernardi
- University
Service Centre for Transmission Electron Microscopy, TU Wien, Wiedner Hauptstraße
8−10, A-1040 Vienna, Austria
| | - Qian Zhao
- Institut
für Physikalische Chemie, Universität Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
| | - Chen Zhuo
- Institut
für Physikalische Chemie, Universität Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
| | - Bernhard Klötzer
- Institut
für Physikalische Chemie, Universität Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
| | - Simon Penner
- Institut
für Physikalische Chemie, Universität Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
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37
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Putz F, Morak R, Elsaesser MS, Balzer C, Braxmeier S, Bernardi J, Paris O, Reichenauer G, Hüsing N. Setting Directions: Anisotropy in Hierarchically Organized Porous Silica. Chem Mater 2017; 29:7969-7975. [PMID: 28989232 PMCID: PMC5627989 DOI: 10.1021/acs.chemmater.7b03032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 08/31/2017] [Indexed: 05/29/2023]
Abstract
Structural hierarchy, porosity, and isotropy/anisotropy are highly relevant factors for mechanical properties and thereby the functionality of porous materials. However, even though anisotropic and hierarchically organized, porous materials are well known in nature, such as bone or wood, producing the synthetic counterparts in the laboratory is difficult. We report for the first time a straightforward combination of sol-gel processing and shear-induced alignment to create hierarchical silica monoliths exhibiting anisotropy on the levels of both, meso- and macropores. The resulting material consists of an anisotropic macroporous network of struts comprising 2D hexagonally organized cylindrical mesopores. While the anisotropy of the mesopores is an inherent feature of the pores formed by liquid crystal templating, the anisotropy of the macropores is induced by shearing of the network. Scanning electron microscopy and small-angle X-ray scattering show that the majority of network forming struts is oriented towards the shearing direction; a quantitative analysis of scattering data confirms that roughly 40% of the strut volume exhibits a preferred orientation. The anisotropy of the material's macroporosity is also reflected in its mechanical properties; i.e., the Young's modulus differs by nearly a factor of 2 between the directions of shear application and perpendicular to it. Unexpectedly, the adsorption-induced strain of the material exhibits little to no anisotropy.
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Affiliation(s)
- Florian Putz
- Chemistry
and Physics of Materials, Paris Lodron University
Salzburg, 5020 Salzburg, Austria
| | - Roland Morak
- Institute
of Physics, Montanuniversität Leoben, 8700 Leoben, Austria
| | - Michael S. Elsaesser
- Chemistry
and Physics of Materials, Paris Lodron University
Salzburg, 5020 Salzburg, Austria
| | - Christian Balzer
- Bavarian
Center for Applied Energy Research, Würzburg, 97074 Würzburg, Germany
| | - Stephan Braxmeier
- Bavarian
Center for Applied Energy Research, Würzburg, 97074 Würzburg, Germany
| | | | - Oskar Paris
- Institute
of Physics, Montanuniversität Leoben, 8700 Leoben, Austria
| | - Gudrun Reichenauer
- Bavarian
Center for Applied Energy Research, Würzburg, 97074 Würzburg, Germany
| | - Nicola Hüsing
- Chemistry
and Physics of Materials, Paris Lodron University
Salzburg, 5020 Salzburg, Austria
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38
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Wolfbeisser A, Kovács G, Kozlov SM, Föttinger K, Bernardi J, Klötzer B, Neyman KM, Rupprechter G. Surface composition changes of CuNi-ZrO2 during methane decomposition: An operando NAP-XPS and density functional study. Catal Today 2017. [DOI: 10.1016/j.cattod.2016.04.022] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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39
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Abstract
Macroporous magnesium silicide monoliths were prepared by a two-step magnesiothermic reaction starting from hierarchically structured silica with silicon as an intermediate step.
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Affiliation(s)
- N. Hayati-Roodbari
- Chemistry and Physics of Materials
- University of Salzburg
- 5020 Salzburg
- Austria
| | - R. J. F. Berger
- Chemistry and Physics of Materials
- University of Salzburg
- 5020 Salzburg
- Austria
| | - J. Bernardi
- USTEM
- Technische Universität Wien
- 1040 Vienna
- Austria
| | - S. Kinge
- Toyota Motors Company Europe
- 2000 Antwerp
- Belgium
| | - N. Hüsing
- Chemistry and Physics of Materials
- University of Salzburg
- 5020 Salzburg
- Austria
| | - M. S. Elsaesser
- Chemistry and Physics of Materials
- University of Salzburg
- 5020 Salzburg
- Austria
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40
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Thomele D, Bourret GR, Bernardi J, Bockstedte M, Diwald O. Hydroxylation Induced Alignment of Metal Oxide Nanocubes. Angew Chem Int Ed Engl 2016; 56:1407-1410. [PMID: 28005313 DOI: 10.1002/anie.201608538] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 10/27/2016] [Indexed: 01/03/2023]
Abstract
Water vapor is ubiquitous under ambient conditions and may alter the shape of nanoparticles. How to utilize water adsorption for nanomaterial functionality and structure formation, however, is a yet unexplored field. Herein, we report the use of water vapor to induce the self-organization of MgO nanocubes into regularly staggered one-dimensional structures. This transformation evolves via an initial alignment of the MgO cubes, the formation of intermediate elongated Mg(OH)2 structures, and their reconversion into MgO cubes arranged in staggered structures. Ab initio DFT modelling identifies surface-energy changes associated with the cube surface hydration and hydroxylation to promote the uncommon staggered stacked assembly of the cubes. This first observation of metal oxide nanoparticle self-organization occurring outside a bulk solution may pave novel routes for inducing texture in ceramics and represents a great test-bed for new surface-science concepts.
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Affiliation(s)
- Daniel Thomele
- Department of Chemistry and Physics of Materials, Paris Lodron University of Salzburg, Hellbrunnerstrasse 34/III, 5020, Salzburg, Austria
| | - Gilles R Bourret
- Department of Chemistry and Physics of Materials, Paris Lodron University of Salzburg, Hellbrunnerstrasse 34/III, 5020, Salzburg, Austria
| | - Johannes Bernardi
- University Service Center for Transmission Electron Microscopy, Vienna University of Technology, Wiedner Hauptstrasse 8-10, 1040, Vienna, Austria
| | - Michel Bockstedte
- Department of Chemistry and Physics of Materials, Paris Lodron University of Salzburg, Hellbrunnerstrasse 34/III, 5020, Salzburg, Austria.,Lehrstuhl für Theoretische Festkörperphysik, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstrasse 7B2, 91058, Erlangen, Germany
| | - Oliver Diwald
- Department of Chemistry and Physics of Materials, Paris Lodron University of Salzburg, Hellbrunnerstrasse 34/III, 5020, Salzburg, Austria
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41
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Thomele D, Bourret GR, Bernardi J, Bockstedte M, Diwald O. Organisation von Metalloxid‐Nanowürfeln durch Hydroxylierung. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201608538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Daniel Thomele
- Fachbereich Chemie und Physik der Materialien Paris Lodron Universität Salzburg Hellbrunnerstraße 34/III 5020 Salzburg Österreich
| | - Gilles R. Bourret
- Fachbereich Chemie und Physik der Materialien Paris Lodron Universität Salzburg Hellbrunnerstraße 34/III 5020 Salzburg Österreich
| | - Johannes Bernardi
- Universitätsservicezentrum für Transmissionselektronenmikroskopie TU Wien Wiedner Hauptstraße 8–10 1040 Wien Österreich
| | - Michel Bockstedte
- Fachbereich Chemie und Physik der Materialien Paris Lodron Universität Salzburg Hellbrunnerstraße 34/III 5020 Salzburg Österreich
- Lehrstuhl für Theoretische Festkörperphysik Friedrich-Alexander-Universität Erlangen-Nürnberg Staudtstraße 7B2 91058 Erlangen Deutschland
| | - Oliver Diwald
- Fachbereich Chemie und Physik der Materialien Paris Lodron Universität Salzburg Hellbrunnerstraße 34/III 5020 Salzburg Österreich
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42
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Wolfbeisser A, Sophiphun O, Bernardi J, Wittayakun J, Föttinger K, Rupprechter G. Methane dry reforming over ceria-zirconia supported Ni catalysts. Catal Today 2016. [DOI: 10.1016/j.cattod.2016.04.025] [Citation(s) in RCA: 166] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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43
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Kocsis K, Niedermaier M, Bernardi J, Berger T, Diwald O. Changing interfaces: Photoluminescent ZnO nanoparticle powders in different aqueous environments. Surf Sci 2016; 652:253-260. [PMID: 32903287 PMCID: PMC7116034 DOI: 10.1016/j.susc.2016.02.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We transformed vapor phase grown ZnO nanoparticle powders into aqueous ZnO nanoparticle dispersions and studied the impact of associated microstructure and interface property changes on their spectroscopic properties. With photoluminescence (PL) spectroscopy, we probed oxygen interstitials O i 2 - in the near surface region and tracked their specific PL emission response at hvEM = 2.1 eV during the controlled conversion of the solid-vacuum into the solid-liquid interface. While oxygen adsorption via the gas phase does affect the intensity of the PL emission bands, the O2 contact with ZnO nanoparticles across the solid-liquid interface does not. Moreover, we found that the near band edge emission feature at hvEM = 3.2 eV gains relative intensity with regard to the PL emission features in the visible light region. Searching for potential PL indicators that are specific to early stages of particle dissolution, we addressed for aqueous ZnO nanoparticle dispersions the effect of formic acid adsorption. In the absence of related spectroscopic features, we were able to consistently track ZnO nanoparticle dissolution and the concomitant formation of sol- vated Zinc formate species by means of PL and FT-IR spectroscopy, dynamic light scattering, and zeta potential measurements. For a more consistent and robust assessment of nanoparticle properties in different continuous phases, we discuss characterization challenges and potential pitfalls that arise upon replacing the solid-gas with the solid-liquid interface.
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Affiliation(s)
- Krisztina Kocsis
- Department of Chemistry and Physics of Materials, Paris Lodron University of Salzburg, Hellbrunnerstrasse 34/III, A - 5020, Salzburg, Austria
| | - Matthias Niedermaier
- Department of Chemistry and Physics of Materials, Paris Lodron University of Salzburg, Hellbrunnerstrasse 34/III, A - 5020, Salzburg, Austria
| | - Johannes Bernardi
- University Service Center for Transmission Electron Microscopy (USTEM), TU Wien, Wiedner Hauptstrasse 8-10, A-1040 Vienna, Austria
| | - Thomas Berger
- Department of Chemistry and Physics of Materials, Paris Lodron University of Salzburg, Hellbrunnerstrasse 34/III, A - 5020, Salzburg, Austria
| | - Oliver Diwald
- Department of Chemistry and Physics of Materials, Paris Lodron University of Salzburg, Hellbrunnerstrasse 34/III, A - 5020, Salzburg, Austria
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44
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Anic K, Wolfbeisser A, Li H, Rameshan C, Föttinger K, Bernardi J, Rupprechter G. Surface Spectroscopy on UHV-Grown and Technological Ni-ZrO 2 Reforming Catalysts: From UHV to Operando Conditions. Top Catal 2016; 59:1614-1627. [PMID: 28035177 PMCID: PMC5153820 DOI: 10.1007/s11244-016-0678-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Ni nanoparticles supported on ZrO2 are a prototypical system for reforming catalysis converting methane to synthesis gas. Herein, we examine this catalyst on a fundamental level using a 2-fold approach employing industrial-grade catalysts as well as surface science based model catalysts. In both cases we examine the atomic (HRTEM/XRD/LEED) and electronic (XPS) structure, as well as the adsorption properties (FTIR/PM-IRAS), with emphasis on in situ/operando studies under atmospheric pressure conditions. For technological Ni–ZrO2 the rather large Ni nanoparticles (about 20 nm diameter) were evenly distributed over the monoclinic zirconia support. In situ FTIR spectroscopy and ex situ XRD revealed that even upon H2 exposure at 673 K no full reduction of the nickel surface was achieved. CO adsorbed reversibly on metallic and oxidic Ni sites but no CO dissociation was observed at room temperature, most likely because the Ni particle edges/steps comprised Ni oxide. CO desorption temperatures were in line with single crystal data, due to the large size of the nanoparticles. During methane dry reforming at 873 K carbon species were deposited on the Ni surface within the first 3 h but the CH4 and CO2 conversion hardly changed even during 24 h. Post reaction TEM and TPO suggest the formation of graphitic and whisker-type carbon that do not significantly block the Ni surface but rather physically block the tube reactor. Reverse water gas shift decreased the H2/CO ratio. Operando studies of methane steam reforming, simultaneously recording FTIR and MS data, detected activated CH4 (CH3 and CH2), activated water (OH), as well as different bidentate (bi)carbonate species, with the latter being involved in the water gas shift side reaction. Surface science Ni–ZrO2 model catalysts were prepared by first growing an ultrathin “trilayer” (O–Zr–O) ZrO2 support on an Pd3Zr alloy substrate, and subsequently depositing Ni, with the process being monitored by XPS and LEED. Apart from the trilayer oxide, there is a small fraction of ZrO2 clusters with more bulk-like properties. When CO was adsorbed on the (fully metallic) Ni particles at pressures up to 100 mbar, both PM-IRAS and XPS indicated CO dissociation around room temperature and blocking of the Ni surface by carbon (note that on the partially oxidized technological Ni particles, CO dissociation was absent). The Ni nanoparticles were stable up to 550 K but annealing to higher temperatures induced Ni migration through the ultrathin ZrO2 support into the Pd3Zr alloy. Both approaches have their benefits and limitations but enable us to address specific questions on a molecular level.
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Affiliation(s)
- Kresimir Anic
- Institute of Materials Chemistry, Technische Universität Wien, Getreidemarkt 9/BC/01, 1060 Vienna, Austria
| | - Astrid Wolfbeisser
- Institute of Materials Chemistry, Technische Universität Wien, Getreidemarkt 9/BC/01, 1060 Vienna, Austria
| | - Hao Li
- Institute of Materials Chemistry, Technische Universität Wien, Getreidemarkt 9/BC/01, 1060 Vienna, Austria
| | - Christoph Rameshan
- Institute of Materials Chemistry, Technische Universität Wien, Getreidemarkt 9/BC/01, 1060 Vienna, Austria
| | - Karin Föttinger
- Institute of Materials Chemistry, Technische Universität Wien, Getreidemarkt 9/BC/01, 1060 Vienna, Austria
| | - Johannes Bernardi
- University Service Center for Transmission Electron Microscopy, Technische Universität Wien, Wiedner Hauptstraße 8-10, 1040 Vienna, Austria
| | - Günther Rupprechter
- Institute of Materials Chemistry, Technische Universität Wien, Getreidemarkt 9/BC/01, 1060 Vienna, Austria
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45
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Mayr L, Klötzer B, Schmidmair D, Köpfle N, Bernardi J, Schwarz S, Armbrüster M, Penner S. Boosting Hydrogen Production from Methanol and Water by in situ Activation of Bimetallic Cu−Zr Species. ChemCatChem 2016. [DOI: 10.1002/cctc.201600361] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Lukas Mayr
- Institut für Physikalische Chemie; Universität Innsbruck; Innrain 80-82 6020 Innsbruck Austria
| | - Bernhard Klötzer
- Institut für Physikalische Chemie; Universität Innsbruck; Innrain 80-82 6020 Innsbruck Austria
| | - Daniela Schmidmair
- Institut für Mineralogie und Petrographie; Universität Innsbruck; Innrain 52f 6020 Innsbruck Austria
| | - Norbert Köpfle
- Institut für Physikalische Chemie; Universität Innsbruck; Innrain 80-82 6020 Innsbruck Austria
| | | | - Sabine Schwarz
- USTEM; TU Wien; Wiedner Hauptstraße 8-10/052 1040 Wien Austria
| | - Marc Armbrüster
- Faculty of Natural Science; Institute of Chemistry; Materials for Innovative Energy Concepts; Technische Universität Chemnitz; 09107 Chemnitz Germany
| | - Simon Penner
- Institut für Physikalische Chemie; Universität Innsbruck; Innrain 80-82 6020 Innsbruck Austria
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46
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Prokofiev A, Svagera R, Waas M, Weil M, Bernardi J, Paschen S. Mechanism of Rare Earth Incorporation and Crystal Growth of Rare Earth Containing Type-I Clathrates. Cryst Growth Des 2016; 16:25-33. [PMID: 26823658 PMCID: PMC4718404 DOI: 10.1021/acs.cgd.5b00461] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Revised: 12/02/2015] [Indexed: 06/05/2023]
Abstract
Type-I clathrates possess extremely low thermal conductivities, a property that makes them promising materials for thermoelectric applications. The incorporation of cerium into one such clathrate has recently been shown to lead to a drastic enhancement of the thermopower, another property determining the thermoelectric efficiency. Here we explore the mechanism of the incorporation of rare earth elements into type-I clathrates. Our investigation of the crystal growth and the composition of the phase Ba8-x RE x TM y Si46-y (RE = rare earth element; TM = Au, Pd, Pt) reveals that the RE content x is mainly governed by two factors, the free cage space and the electron balance.
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Affiliation(s)
- Andrey Prokofiev
- Institute
of Solid State Physics, Vienna University
of Technology, Wiedner
Hauptstrasse 8-10, Vienna 1040, Austria
| | - Robert Svagera
- Institute
of Solid State Physics, Vienna University
of Technology, Wiedner
Hauptstrasse 8-10, Vienna 1040, Austria
| | - Monika Waas
- Institute
of Solid State Physics, Vienna University
of Technology, Wiedner
Hauptstrasse 8-10, Vienna 1040, Austria
| | - Matthias Weil
- Institute
of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/164-SC, 1060 Vienna, Austria
| | | | - Silke Paschen
- Institute
of Solid State Physics, Vienna University
of Technology, Wiedner
Hauptstrasse 8-10, Vienna 1040, Austria
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47
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Datler M, Bespalov I, Buhr S, Zeininger J, Stöger-Pollach M, Bernardi J, Rupprechter G, Suchorski Y. Hydrogen Oxidation on Stepped Rh Surfaces: µm-Scale versus Nanoscale. Catal Letters 2016; 146:1867-1874. [PMID: 32355436 PMCID: PMC7175702 DOI: 10.1007/s10562-016-1824-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 07/21/2016] [Indexed: 11/11/2022]
Abstract
Abstract The catalytic H2 oxidation reaction on stepped Rh surfaces in the 10−6 mbar pressure range was studied in situ on individual high-Miller-index domains of a polycrystalline Rh foil by PEEM (photoemission electron microscopy) and on a Rh nanotip by FIM/FEM (field-ion/field-emission microscopy). The activity, particularly the tolerance to poisoning by oxygen, was found to strongly depend on the density of steps and defects, as well as on the size of the catalytically active surfaces. Graphical Abstract ![]()
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Affiliation(s)
- M Datler
- 1Institute of Materials Chemistry, Technische Universität Wien, 1060 Vienna, Austria
| | - I Bespalov
- 1Institute of Materials Chemistry, Technische Universität Wien, 1060 Vienna, Austria
| | - S Buhr
- 1Institute of Materials Chemistry, Technische Universität Wien, 1060 Vienna, Austria
| | - J Zeininger
- 1Institute of Materials Chemistry, Technische Universität Wien, 1060 Vienna, Austria
| | - M Stöger-Pollach
- 2University Service Center for Transmission Electron Microscopy, Technische Universität Wien, 1060 Vienna, Austria
| | - J Bernardi
- 2University Service Center for Transmission Electron Microscopy, Technische Universität Wien, 1060 Vienna, Austria
| | - G Rupprechter
- 1Institute of Materials Chemistry, Technische Universität Wien, 1060 Vienna, Austria
| | - Y Suchorski
- 1Institute of Materials Chemistry, Technische Universität Wien, 1060 Vienna, Austria
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Schneider J, Franke M, Gurrath M, Röckert M, Berger T, Bernardi J, Meyer B, Steinrück HP, Lytken O, Diwald O. Porphyrin Metalation at MgO Surfaces: A Spectroscopic and Quantum Mechanical Study on Complementary Model Systems. Chemistry 2015; 22:1744-9. [PMID: 26682774 DOI: 10.1002/chem.201503661] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Indexed: 11/05/2022]
Abstract
We show that both single-crystalline and nanostructured MgO surfaces convert free-base tetraphenyl porphyrin (2HTPP) into magnesium tetraphenyl porphyrin (MgTPP) at room temperature. The reaction can be viewed as an ion exchange between the two aminic protons of the 2HTPP molecule with a Mg(2+) ion from the surface. The driving force for the reaction is the strong stability of the formed hydroxyl groups along the steps and at defects on the MgO surface. We have used an integrated characterization approach that includes UV/Vis diffuse reflectance measurements on nanostructured powders, X-ray photoelectron spectroscopic investigation of atomically clean MgO(100) single-crystalline thin films, and density functional theory (DFT) calculations on model systems. The DFT calculations demonstrate that MgTPP formation is strongly exothermic at the corners, edges and steps, but slightly endothermic on terrace sites. This agrees well with the UV/Vis diffuse reflectance, which upon adsorption of 2HTPP shows a decrease in the absorption band associated with corner and edge sites on MgO nanocube powders.
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Affiliation(s)
- Johannes Schneider
- Department of Chemistry & Physics of Materials, Paris-Lodron University Salzburg, Salzburg, Austria
| | - Matthias Franke
- Institute of Physical Chemistry II, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Martin Gurrath
- Interdisciplinary Center for Molecular Materials (ICMM) and Computer-Chemistry-Center (CCC), Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Michael Röckert
- Institute of Physical Chemistry II, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Thomas Berger
- Department of Chemistry & Physics of Materials, Paris-Lodron University Salzburg, Salzburg, Austria
| | - Johannes Bernardi
- University Service Centre for Transmission Electron Microscopy, Vienna University of Technology, Vienna, Austria
| | - Bernd Meyer
- Interdisciplinary Center for Molecular Materials (ICMM) and Computer-Chemistry-Center (CCC), Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany.
| | - Hans-Peter Steinrück
- Institute of Physical Chemistry II, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Ole Lytken
- Institute of Physical Chemistry II, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany.
| | - Oliver Diwald
- Department of Chemistry & Physics of Materials, Paris-Lodron University Salzburg, Salzburg, Austria.
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Luczynski KW, Steiger-Thirsfeld A, Bernardi J, Eberhardsteiner J, Hellmich C. Extracellular bone matrix exhibits hardening elastoplasticity and more than double cortical strength: Evidence from homogeneous compression of non-tapered single micron-sized pillars welded to a rigid substrate. J Mech Behav Biomed Mater 2015; 52:51-62. [DOI: 10.1016/j.jmbbm.2015.03.001] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Revised: 02/13/2015] [Accepted: 03/01/2015] [Indexed: 11/17/2022]
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Sologub O, Salamakha L, Rogl P, Stöger B, Bauer E, Bernardi J, Giester G, Waas M, Svagera R. Pt–B System Revisited: Pt2B, a New Structure Type of Binary Borides. Ternary WAl12-Type Derivative Borides. Inorg Chem 2015; 54:10958-65. [DOI: 10.1021/acs.inorgchem.5b01998] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Oksana Sologub
- Institute of Solid State Physics, TU Wien, A-1040 Vienna, Austria
| | - Leonid Salamakha
- Institute of Solid State Physics, TU Wien, A-1040 Vienna, Austria
| | - Peter Rogl
- Institute of Materials Chemistry and Research, University of Vienna, A-1090 Vienna, Austria
| | - Berthold Stöger
- Institute for Chemical
Technologies and Analytics, TU Wien, A-1040 Vienna, Austria
| | - Ernst Bauer
- Institute of Solid State Physics, TU Wien, A-1040 Vienna, Austria
| | - Johannes Bernardi
- University Service Center for TEM (USTEM), TU Wien, A-1040 Vienna, Austria
| | - Gerald Giester
- Institute of Mineralogy and Crystallography, University of Vienna, A-1090 Vienna, Austria
| | - Monika Waas
- Institute of Solid State Physics, TU Wien, A-1040 Vienna, Austria
| | - Robert Svagera
- Institute of Solid State Physics, TU Wien, A-1040 Vienna, Austria
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