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SECTOR - Structural-induced electronic complexity controlled by low temperature topotactic reactions

Applicant Keller Lukas
Number 157131
Funding scheme Project funding (Div. I-III)
Research institution Paul Scherrer Institut
Institution of higher education Paul Scherrer Institute - PSI
Main discipline Condensed Matter Physics
Start/End 01.09.2015 - 31.08.2019
Approved amount 282'597.00
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Keywords (5)

oxygen mobility; electronic and structural correlations; structural disorder; low-temperature reactivity; transition metal oxides

Lay Summary (German)

Lead
Wir untersuchen komplexe Ordnungsphänomene und die damit verbundenen Änderungen in den physikalischen und chemischen Eigenschaften in nicht-stöchiometrischen Oxiden. Dabei wird der Sauerstoffgehalt mittels einer elektrochemischen Reaktion bei tiefen Temperaturen gesteuert.
Lay summary

Inhalt und Ziel des Forschungsprojektes

Materialien mit stark korrelierten Elektronen sind von grossem Interesse aufgrund ihrer besonderen Eigenschaften wie Hochtemperatursupraleitung und Riesenmagnetowiderstand. In den letzten Jahren trat die Rolle von Fehlordnung und lokalen Strukturen, und deren Einfluss auf die elektronischen Eigenschaften, immer mehr ins Zentrum der Forschung. Die Stärke unseres Forschungsvorhabens ist die Kombination von chemischen und festkörper-physikalischen Methoden mit dem Fokus auf topotaktische Oxidierung bei tiefen Temperaturen, sowie der damit verbundenen Möglichkeit zur Synthese von langreichweitig wohlgeordneten und spannungsfreien Einkristallen. Die Ergebnisse aus den geplanten Untersuchungen der elektronischen Eigenschaften werden direkt die Untersuchung des Einflusses von Fehlstellen in dotierten Perowskiten beeinflussen, insbesondere in Hinblick auf den Mechanismus der Hochtemperatur-Supraleitung in Kupraten. Mit topotaktischen Reaktionen bei niedrigen Temperaturen haben wir eine bemerkenswerte Methode, um neue Verbindungen zu synthetisieren. Dies gilt für die Menge des eingelagerten Sauerstoffs, aber auch in Bezug auf spezifische Reaktionsmechanismen, die Freisetzung und Aufnahme von Sauerstoff und somit ungewöhnliche Wertigkeit und neue Koordinationszustände ermöglichen.

Wissenschaftlicher und gesellschaftlicher Kontext des Forschungsprojektes

Topotaktische Reaktionen bei tiefen Temperaturen werden zukünftige Anwendungen in Festoxidbrennstoffzellen (solid oxide fuel cells, SOFC) direkt beeinflussen. Die Niedertemperatur-SOFC können eine Antwort für unsere zukünftigen Mobilitätsbedürfnisse sein. Ebenso besteht im Zusammenhang mit der Energiewende und dem Umstieg von nuklearer und fossiler Energieerzeugung zu erneuerbaren Energieträgern ein ausserordentlicher Bedarf für hocheffiziente, stabile, kostengünstige und in grossem Massstab verfügbare Energiespeichersysteme.
Direct link to Lay Summary Last update: 29.06.2015

Responsible applicant and co-applicants

Employees

Publications

Publication
Long-range oxygen ordering linked to topotactic oxygen release in Pr2NiO4+d fuel cell cathode material
Dutta Rajesh, Maity Avishek, Marsicano Anna, Ceretti Monica, Chernyshov Dmitry, Bosak Alexeï, Villesuzanne Antoine, Roth Georg, Perversi Giuditta, Paulus Werner (2020), Long-range oxygen ordering linked to topotactic oxygen release in Pr2NiO4+d fuel cell cathode material, in Journal of Materials Chemistry A.
Structural disorder and magnetic correlations driven by oxygen doping in Nd2NiO4+δ ( δ∼0.11 )
Maity Sumit Ranjan, Ceretti Monica, Keller Lukas, Schefer Jürg, Shang Tian, Pomjakushina Ekaterina, Meven Martin, Sheptyakov Denis, Cervellino Antonio, Paulus Werner (2019), Structural disorder and magnetic correlations driven by oxygen doping in Nd2NiO4+δ ( δ∼0.11 ), in Physical Review Materials, 3(8), 083604-083604.
Neutron diffraction studies of oxygen disorder in Nd 2 NiO 4+ d
Maity Sumit Ranjan, Keller Lukas, Schefer Juerg, Ceretti Monica, Paulus Werner (2018), Neutron diffraction studies of oxygen disorder in Nd 2 NiO 4+ d, in Acta Crystallographica Section A Foundations and Advances, 74(a2), e69-e70.
(Nd/Pr) 2 NiO 4+δ : Reaction Intermediates and Redox Behavior Explored by in Situ Neutron Powder Diffraction during Electrochemical Oxygen Intercalation
Ceretti Monica, Wahyudi Olivia, André Gilles, Meven Martin, Villesuzanne Antoine, Paulus Werner (2018), (Nd/Pr) 2 NiO 4+δ : Reaction Intermediates and Redox Behavior Explored by in Situ Neutron Powder Diffraction during Electrochemical Oxygen Intercalation, in Inorganic Chemistry, 57(8), 4657-4666.
Neutron diffraction studies of oxygen disorder in Nd 2 NiO 4+ d
Maity Sumit Ranjan, Schefer Juerg, Keller Lukas, Ceretti Monica, Paulus Werner (2017), Neutron diffraction studies of oxygen disorder in Nd 2 NiO 4+ d, in Acta Crystallographica Section A Foundations and Advances, 73(a2), C1426-C1426.
Temperature dependent structural studies of the oxygen ion conductor Pr 1.5 Sr 0.5 NiO 4+d investigated by single crystal neutron diffraction
Maity Sumit R., Ceretti Monica, Meven Martin, Schefer Jurg, Keller Lukas, Petry Winfried, Paulus Werner (2016), Temperature dependent structural studies of the oxygen ion conductor Pr 1.5 Sr 0.5 NiO 4+d investigated by single crystal neutron diffraction, in Acta Crystallographica Section A Foundations and Advances, 72(a1), s287-s287.

Collaboration

Group / person Country
Types of collaboration
Paul Scherrer Institut, Laboratory for Multiscale Materials Experiments, Dr. Ekaterina Pomjakushina Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
- Research Infrastructure
Paul Scherrer Institut, Laboratory for Neutron and Muon Instrumentation, Dr. Marek Bartkowiak Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Research Infrastructure
University Montpellier 1, UR1, C2M, Chimie et Cristallochimie des Matériaux, Prof. Dr. W. Paulus France (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
- Research Infrastructure
- Exchange of personnel

Scientific events

Active participation

Title Type of contribution Title of article or contribution Date Place Persons involved
European Crystallographic Meeting, ECM32 Poster Structural disorder and magnetic correlations driven by oxygen doping in Nd2NiO4.11 18.08.2019 Wien, Austria Keller Lukas; Paulus Werner; Schefer Jürg;
SGK-SSCR Swiss Society for Crystallography Annual Meeting 2018 Individual talk Incommensurate crystal structure and magnetism in oxygen doped Nd2NiO4+δ 12.09.2018 Villigen PSI, Switzerland Maity Summit Ranjan; Keller Lukas;
European Crystallographic Meeting, ECM 31 Talk given at a conference Neutron diffraction studies of apical oxygen disorder and incommensurate magnetic order in Nd2NiO4+δ 22.08.2018 Oviedo, Spain Paulus Werner; Maity Summit Ranjan; Schefer Jürg;
24th Congress and General Assembly of the International Union of Crystallography, IUCr 2017 Individual talk Neutron diffraction studies of apical oxygen disorder in Nd2NiO4+δ 21.08.2017 Hyderabad, India Maity Summit Ranjan;
Kolloquium, Paul Scherrer Institut Individual talk Structural-induced electronic complexity in Nd2NiO4+d 24.10.2016 Villigen PSI, Switzerland Maity Summit Ranjan;
European Crystallographic Meeting, ECM 30 Poster Crystal structure and apical oxygen disorder in Nd2NiO4+δ explored by neutron diffraction 28.08.2016 Basel, Switzerland Schefer Jürg; Keller Lukas; Maity Summit Ranjan; Paulus Werner;
MLZ conference: Neutrons for Energy Poster Effect of doping and temperature on oxygen disorder in Pr2NiO4+δ explored by single crystal neutron diffraction 18.07.2016 Bad Reichenhall, Germany Maity Summit Ranjan;


Associated projects

Number Title Start Funding scheme
170773 A new high efficiency two-dimensional neutron detector for the cold-neutron diffractometer DMC at SINQ 01.11.2017 R'EQUIP

Abstract

We propose to study complex ordering phenomena and associated changes in the physical and chemical properties in non-stoichiometric oxides using a low temperature electrochemical reaction to control the oxygen content in two related structure families: Brownmillerites, which are oxygen deficient Perovskites and Ruddlesden-Popper phases with K2NiF4-type structure. These compounds are complex due to the many active degrees of freedom such as charge, spin and orbital ordering, which interact in a competitive, synergetic way. The principal aim of this proposal is to explore the limits of structural correlations and associated phase diagrams for selected Ruddlesden-Popper (R2MO4 , R = La, Nd, Pr,…, M = Cu, Ni, Co,…) and Brownmillerite type oxides (Sr2(Fe/Co)O5), and to explore to which extend they are homogeneous. On the other hand these giant correlations have not only structural implications (for example, La2CoO4.25 yields strong correlations with a unit cell volume of 25.000 Å3, Pr2NiO4.25 exceeds this quantity by far with 3.000.000 Å3), but consequently imply electronic ordering and lattice dynamical properties. Beside electronic correlations, lattice dynamics is here of special interest, as we were able to recently evidence for both oxide families phonon assisted oxygen diffusion activated already at ambient temperature. Thus, structural instabilities and associated creation of low energy phonon modes is assumed to be a prerequisite for low temperature oxygen diffusion in these types of frameworks. Correlated phonon modes create large displacement amplitudes of oxygen atoms and generate oxygen diffusion pathways with shallow activation energies thus become another important issue in these strongly correlated electronic systems. Structural, electronic and lattice dynamical correlations will be explored via a multi-technical approach combining structure and dynamic studies importantly carried out under in in situ conditions during oxygen intercalation reactions in especially constructed electrochemical cells taking care of complementary advantages of synchrotron radiation (diffraction, inelastic X-ray scattering, XAFS, soft resonance scattering) and neutron scattering techniques (diffraction, spectroscopy). The specific approach here is that an important part of proposed experiments will be carried out in-situ on single crystals. The feasibility of these types of studies has already been successfully demonstrated. The better understanding of the mechanisms allowing low temperature oxygen ion mobility in solid oxides is of fundamental and applied interest, as for the development and conception of oxygen membranes in solid oxide fuel cells (SOFC), sensors or electro-catalysts.We submit this research proposal under the lead agency process between the SNF and the ANR with the intention to maximize the efficiency in the research of non-stoichiometric oxides at the Paul Scherrer Institut (PSI) and the University of Montpellier (UM). The institutes complement each other perfectly with the resources on large scale facility research (µSR, Synchrotron radiation and Neutron source) at the PSI and the facilities for single crystal synthesis and electrochemistry at the University of Montpellier, France.
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