Mierwaldt, Daniel

[["dc.bibliographiccitation.artnumber","243502"],["dc.bibliographiccitation.issue","24"],["dc.bibliographiccitation.journal","Applied Physics Letters"],["dc.bibliographiccitation.volume","110"],["dc.contributor.author","Kramer, Thilo"],["dc.contributor.author","Scherff, Malte"],["dc.contributor.author","Mierwaldt, Daniel"],["dc.contributor.author","Hoffmann, Joerg"],["dc.contributor.author","Jooss, Christian"],["dc.date.accessioned","2018-11-07T10:22:44Z"],["dc.date.available","2018-11-07T10:22:44Z"],["dc.date.issued","2017"],["dc.description.abstract","Non-volatile resistance change under electric stimulation in oxides is a promising path to next generation memory devices. However, the underlying mechanisms are still not fully understood. We report here on the study of switching in Pr0.67Ca0.33MnO3-delta (PCMO) films sandwiched by noble metal Pt electrodes, where electrode oxidation can be excluded. In order to develop an understanding of the switching induced oxygen migration, its initial concentration is modified by post-annealing of the deposited PCMO films. The oxygen distribution is obtained by manganese valence determination using spatially resolved electron energy loss spectroscopy in scanning transmission electron microscopy mode. We observe correlations between virgin state resistance, resistive switching properties, oxygen vacancy distribution, and stress/strain state of the PCMO films and propose a simplified interface resistance model based on the measured valence distribution. It assumes a linear correlation of oxygen vacancy concentration with conductivity and a metal to insulator transition above a critical vacancy concentration threshold. Our results suggest that resistance changes can take place at both interfaces of symmetric devices and only requires small changes in oxygen vacancy concentration. (C) 2017 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/)."],["dc.description.sponsorship","DFG [Jo 348/10-01]"],["dc.identifier.doi","10.1063/1.4985645"],["dc.identifier.isi","000403678300029"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/42329"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.issn","1077-3118"],["dc.relation.issn","0003-6951"],["dc.relation.orgunit","Institut für Materialphysik"],["dc.title","Role of oxygen vacancies for resistive switching in noble metal sandwiched Pr0.67Ca0.33MnO3-delta"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1700109"],["dc.bibliographiccitation.issue","12"],["dc.bibliographiccitation.journal","Advanced sustainable systems"],["dc.bibliographiccitation.volume","1"],["dc.contributor.author","Mierwaldt, Daniel"],["dc.contributor.author","Roddatis, Vladimir"],["dc.contributor.author","Risch, Marcel"],["dc.contributor.author","Scholz, Julius"],["dc.contributor.author","Geppert, Janis"],["dc.contributor.author","Abrishami, Majid Ebrahimizadeh"],["dc.contributor.author","Jooss, Christian"],["dc.date.accessioned","2020-12-10T14:06:44Z"],["dc.date.available","2020-12-10T14:06:44Z"],["dc.date.issued","2017"],["dc.identifier.doi","10.1002/adsu.201700109"],["dc.identifier.issn","2366-7486"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/70006"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-354"],["dc.relation","SFB 1073: Kontrolle von Energiewandlung auf atomaren Skalen"],["dc.relation","SFB 1073 | Topical Area C | C02 In situ hochauflösende Untersuchung des aktiven Zustands bei der photo- und elektrochemischen Wasserspaltung"],["dc.relation.orgunit","Institut für Materialphysik"],["dc.rights","CC BY-NC 4.0"],["dc.title","Environmental TEM Investigation of Electrochemical Stability of Perovskite and Ruddlesden-Popper Type Manganite Oxygen Evolution Catalysts"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","129"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","Catalysts"],["dc.bibliographiccitation.lastpage","145"],["dc.bibliographiccitation.volume","4"],["dc.contributor.author","Mierwaldt, Daniel"],["dc.contributor.author","Mildner, Stephanie"],["dc.contributor.author","Arrigo, Rosa"],["dc.contributor.author","Knop-Gericke, Axel"],["dc.contributor.author","Franke, Emanuel"],["dc.contributor.author","Blumenstein, Andreas"],["dc.contributor.author","Hoffmann, Joerg"],["dc.contributor.author","Jooß, Christian"],["dc.date.accessioned","2018-11-07T09:39:09Z"],["dc.date.available","2018-11-07T09:39:09Z"],["dc.date.issued","2014"],["dc.description.abstract","Studying catalysts in situ is of high interest for understanding their surface structure and electronic states in operation. Herein, we present a study of epitaxial manganite perovskite thin films (Pr1-xCaxMnO3) active for the oxygen evolution reaction (OER) from electro-catalytic water splitting. X-ray absorption near-edge spectroscopy (XANES) at the Mn L- and O K-edges, as well as X-ray photoemission spectroscopy (XPS) of the O 1s and Ca 2p states have been performed in ultra-high vacuum and in water vapor under positive applied bias at room temperature. It is shown that under the oxidizing conditions of the OER a reduced Mn2+ species is generated at the catalyst surface. The Mn valence shift is accompanied by the formation of surface oxygen vacancies. Annealing of the catalysts in O-2 atmosphere at 120 degrees C restores the virgin surfaces."],["dc.description.sponsorship","DFG CRC 1073 project C02"],["dc.description.sponsorship","Deutsche Forschungsgemeinschaft through the CRC 1073 [C02]"],["dc.identifier.doi","10.3390/catal4020129"],["dc.identifier.isi","000339590600004"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/10510"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/33215"],["dc.notes","Financial support by the Deutsche Forschungsgemeinschaft through the CRC 1073 project C02"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.relation","SFB 1073: Kontrolle von Energiewandlung auf atomaren Skalen"],["dc.relation","SFB 1073 | Topical Area C | C02 In situ hochauflösende Untersuchung des aktiven Zustands bei der photo- und elektrochemischen Wasserspaltung"],["dc.relation.issn","2073-4344"],["dc.relation.orgunit","Fakultät für Physik"],["dc.relation.orgunit","Institut für Materialphysik"],["dc.title","In Situ XANES/XPS Investigation of Doped Manganese Perovskite Catalysts"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","3378"],["dc.bibliographiccitation.issue","16"],["dc.bibliographiccitation.journal","Advanced Functional Materials"],["dc.bibliographiccitation.lastpage","3388"],["dc.bibliographiccitation.volume","22"],["dc.contributor.author","Raabe, Stephanie"],["dc.contributor.author","Mierwaldt, Daniel"],["dc.contributor.author","Ciston, Jim"],["dc.contributor.author","Uijttewaal, Matthe"],["dc.contributor.author","Stein, Helge"],["dc.contributor.author","Hoffmann, Joerg"],["dc.contributor.author","Zhu, Y."],["dc.contributor.author","Bloechl, Peter E."],["dc.contributor.author","Jooss, Christian"],["dc.date.accessioned","2018-11-07T09:07:08Z"],["dc.date.available","2018-11-07T09:07:08Z"],["dc.date.issued","2012"],["dc.description.abstract","Fundamental studies of catalysts based on manganese oxide compounds are of high interest since they offer the opportunity to study the role of variable valence state in the active state during O2 evolution from H2O. This paper presents a study of doping dependent O2 evolution electrocatalysis of Pr-doped CaMnO3 via in situ environmental transmission electron microscopy (ETEM) combined with ex situ cyclic voltammetry studies. ETEM studies of heterogeneous catalysis are a challenge, since the reactions in the H2O vapor phase cannot directly be observed. It is shown that the oxidation of silane by free oxygen to solid SiO2-x can be used to monitor catalytic oxygen evolution. Electron energy loss spectroscopy (EELS) as well as the in situ X-ray absorption study of near edge structures (XANES) in H2O vapor reveals that the Mn valence is decreased in the active state. Careful TEM analysis of samples measured by ex situ cyclic voltammetry and an in situ bias-controlled ETEM study allows us to distinguish between self-formation during oxygen evolution and corrosion at the Pr1-xCaxMnO3-H2O interface. Including density functional theory (DFT) calculations, trends in O2 evolution activity and defect chemistry in the active state can be correclated to doping induced changes of the electronic band structure in A-site doped manganites."],["dc.identifier.doi","10.1002/adfm.201103173"],["dc.identifier.isi","000307566200003"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/25721"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.relation.issn","1616-3028"],["dc.relation.issn","1616-301X"],["dc.relation.orgunit","Institut für Materialphysik"],["dc.title","In Situ Electrochemical Electron Microscopy Study of Oxygen Evolution Activity of Doped Manganite Perovskites"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","61"],["dc.bibliographiccitation.journal","Ultramicroscopy"],["dc.bibliographiccitation.lastpage","70"],["dc.bibliographiccitation.volume","184"],["dc.contributor.author","Kramer, Thilo"],["dc.contributor.author","Mierwaldt, Daniel"],["dc.contributor.author","Scherff, Malte"],["dc.contributor.author","Kanbach, Mike"],["dc.contributor.author","Jooss, Christian"],["dc.date.accessioned","2020-12-10T15:21:40Z"],["dc.date.available","2020-12-10T15:21:40Z"],["dc.date.issued","2018"],["dc.identifier.doi","10.1016/j.ultramic.2017.08.012"],["dc.identifier.issn","0304-3991"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/73108"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-354"],["dc.relation.orgunit","Institut für Materialphysik"],["dc.title","Developing an in situ environmental TEM set up for investigations of resistive switching mechanisms in Pt-Pr1-xCaxMnO3-δ-Pt sandwich structures"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","302"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Journal of Synchrotron Radiation"],["dc.bibliographiccitation.lastpage","306"],["dc.bibliographiccitation.volume","24"],["dc.contributor.author","Yin, Zhong"],["dc.contributor.author","Peters, Hans-Bernhard"],["dc.contributor.author","Hahn, Ulrich"],["dc.contributor.author","Gonschior, Josef"],["dc.contributor.author","Mierwaldt, Daniel"],["dc.contributor.author","Rajkovic, Ivan"],["dc.contributor.author","Viefhaus, Jens"],["dc.contributor.author","Jooss, Christian"],["dc.contributor.author","Techert, Simone"],["dc.date.accessioned","2020-12-10T18:25:57Z"],["dc.date.available","2020-12-10T18:25:57Z"],["dc.date.issued","2017"],["dc.description.abstract","A novel experimental setup is presented for resonant inelastic X-ray scattering investigations of solid and liquid samples in the soft X-ray region for studying the complex electronic configuration of (bio) chemical systems. The uniqueness of the apparatus is its high flexibility combined with optimal energy resolution and energy range ratio. The apparatus enables investigation of chemical analyses, which reflects the chemical imprints. The endstation is composed of a main sample chamber, a sample holder for either solid or liquid jet delivery system, and a soft X-ray grating spectrometer for 210-1250 eV with a resolving power of similar to 1000. It combines for the first time liquid jet technology with a soft X-ray spectrometer based on the variable line spacing principle. This setup was commissioned at the soft X-ray beamline P04 at PETRA III of the Deutsches Elektronen-Synchrotron in Hamburg which is currently the most brilliant storage-ring-based X-ray radiation source in the world. The first results of liquid and solid samples show that this setup allows the detection of photons across an energy range of similar to 300 eV. This covers simultaneously the emission lines of life-important elements like carbon, nitrogen and oxygen in a shot-based procedure."],["dc.identifier.doi","10.1107/S1600577516016611"],["dc.identifier.isi","000391724900031"],["dc.identifier.pmid","28009571"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/75894"],["dc.notes.intern","DOI Import GROB-354"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","PUB_WoS_Import"],["dc.publisher","Int Union Crystallography"],["dc.publisher.place","Chester"],["dc.relation","SFB 1073: Kontrolle von Energiewandlung auf atomaren Skalen"],["dc.relation","SFB 1073 | Topical Area C | C02 In situ hochauflösende Untersuchung des aktiven Zustands bei der photo- und elektrochemischen Wasserspaltung"],["dc.relation.eventend","2016-03-11"],["dc.relation.eventlocation","Lund, SWEDEN"],["dc.relation.eventstart","2016-03-09"],["dc.relation.issn","1600-5775"],["dc.relation.orgunit","Institut für Materialphysik"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Techert (Structural Dynamics in Chemical Systems)"],["dc.title","An endstation for resonant inelastic X-ray scattering studies of solid and liquid samples"],["dc.type","conference_paper"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","7893"],["dc.bibliographiccitation.issue","14"],["dc.bibliographiccitation.journal","The Journal of Physical Chemistry C"],["dc.bibliographiccitation.lastpage","7902"],["dc.bibliographiccitation.volume","124"],["dc.contributor.author","Busse, Philipp"],["dc.contributor.author","Yin, Zhong"],["dc.contributor.author","Mierwaldt, Daniel"],["dc.contributor.author","Scholz, Julius"],["dc.contributor.author","Kressdorf, Birte"],["dc.contributor.author","Glaser, Leif"],["dc.contributor.author","Miedema, Piter S."],["dc.contributor.author","Rothkirch, André"],["dc.contributor.author","Viefhaus, Jens"],["dc.contributor.author","Jooss, Christian"],["dc.contributor.author","Techert, Simone"],["dc.contributor.author","Risch, Marcel"],["dc.date.accessioned","2020-12-10T15:22:44Z"],["dc.date.available","2020-12-10T15:22:44Z"],["dc.date.issued","2020"],["dc.identifier.doi","10.1021/acs.jpcc.0c00840"],["dc.identifier.eissn","1932-7455"],["dc.identifier.issn","1932-7447"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/73515"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-354"],["dc.relation","SFB 1073: Kontrolle von Energiewandlung auf atomaren Skalen"],["dc.relation","SFB 1073 | Topical Area B | B06 Echtzeituntersuchungen der optischen Anregung in oligonuklearen Metallkomplexen mit schaltbaren Spin- und Ladungszuständen"],["dc.relation","SFB 1073 | Topical Area C | C01 Hydrid-Anordnungen für die Untersuchung photo-induzierter mehrstufiger katalytischer Prozesse"],["dc.relation","SFB 1073 | Topical Area C | C02 In situ hochauflösende Untersuchung des aktiven Zustands bei der photo- und elektrochemischen Wasserspaltung"],["dc.relation","SFB 1073 | Topical Area C | C05 Kontrolle Elektronen-getriebener Chemie durch Interkalation"],["dc.relation.orgunit","Institut für Materialphysik"],["dc.relation.workinggroup","RG Techert (Structural Dynamics in Chemical Systems)"],["dc.title","Probing the Surface of La0.6Sr0.4MnO3 in Water Vapor by In Situ Photon-In/Photon-Out Spectroscopy"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","5301"],["dc.bibliographiccitation.issue","10"],["dc.bibliographiccitation.journal","The Journal of Physical Chemistry C"],["dc.bibliographiccitation.lastpage","5310"],["dc.bibliographiccitation.volume","119"],["dc.contributor.author","Mildner, Stephanie"],["dc.contributor.author","Beleggia, Marco"],["dc.contributor.author","Mierwaldt, Daniel"],["dc.contributor.author","Hansen, Thomas W."],["dc.contributor.author","Wagner, Jakob B."],["dc.contributor.author","Yazdi, Sadegh"],["dc.contributor.author","Kasama, Takeshi"],["dc.contributor.author","Ciston, Jim"],["dc.contributor.author","Zhu, Y."],["dc.contributor.author","Jooß, Christian"],["dc.date.accessioned","2018-11-07T09:59:43Z"],["dc.date.available","2018-11-07T09:59:43Z"],["dc.date.issued","2015"],["dc.description.abstract","Environmental transmission electron microscopy (ETEVI) studies offer great potential for gathering atomic scale information on the electronic state of electrodes in contact with reactants. It also poses big challenges due to the impact of the high energy electron beam. In this article, we present an ETEM study of a Pr0.64Ca0.36MnO3 (PCMO) thin filth electrocatalySt for water splitting and Oxygen evolution in contact with water vapor: We show by means of off-axis electron holography and electrostatic modeling that the electron beam gives rise to a positive electric sample potential due to secondary electron emission. The value of the electric potential depends on the primary electron flux, the sample's electric Conductivity and grounding, and gas properties. We present evidence that two observed electrochemical reactions are driven by a beam induced electrostatic potential of the order of a volt. The first reaction is an anodic oxidation of oxygen depleted amorphous PCMO which results in recrystallization of the oxide. The Second reaction is oxygen evolution which can be detected by the oxidation of a silane additive and formation of SiO2-gamma at catalytically active surfaces. The quantification of beam induced potentials is an important step for future controlled electrochemical experiments in an ETEM."],["dc.description.sponsorship","DFG [SFB 1073]"],["dc.identifier.doi","10.1021/jp511628c"],["dc.identifier.isi","000351189100006"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/37654"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.relation","SFB 1073: Kontrolle von Energiewandlung auf atomaren Skalen"],["dc.relation","SFB 1073 | Topical Area C | C02 In situ hochauflösende Untersuchung des aktiven Zustands bei der photo- und elektrochemischen Wasserspaltung"],["dc.relation.issn","1932-7447"],["dc.relation.orgunit","Institut für Materialphysik"],["dc.title","Environmental TEM Study of Electron Beam Induced Electrochemistry of Pr0.64Ca0.36MnO3 Catalysts for Oxygen Evolution"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","235150"],["dc.bibliographiccitation.issue","23"],["dc.bibliographiccitation.journal","Physical Review B"],["dc.bibliographiccitation.volume","95"],["dc.contributor.author","Sotoudeh, Mohsen"],["dc.contributor.author","Rajpurohit, Sangeeta"],["dc.contributor.author","Blöchl, Peter"],["dc.contributor.author","Mierwaldt, Daniel"],["dc.contributor.author","Norpoth, Jonas"],["dc.contributor.author","Roddatis, Vladimir"],["dc.contributor.author","Mildner, Stephanie"],["dc.contributor.author","Kressdorf, Birte"],["dc.contributor.author","Ifland, Benedikt"],["dc.contributor.author","Jooss, Christian"],["dc.date.accessioned","2020-12-10T18:25:03Z"],["dc.date.available","2020-12-10T18:25:03Z"],["dc.date.issued","2017"],["dc.description.abstract","The electronic structure of Pr1-xCaxMnO3 has been investigated using a combination of first-principles calculations, x-ray photoelectron spectroscopy (XPS), x-ray absorption spectroscopy (XAS), electron-energy loss spectroscopy (EELS), and optical absorption. The full range of compositions, x = 0,1/2,1, and a variety of magnetic orders have been covered. Jahn-Teller as well as Zener polaron orders are considered. The free parameters of the local hybrid density functionals used in this study have been determined by comparison with measured XPS spectra. A model Hamiltonian, valid for the entire doping range, has been extracted. A simple local-orbital picture of the electronic structure for the interpretation of experimental spectra is provided. The comparison of theoretical calculations and different experimental spectra provide a detailed and consistent picture of the electronic structure. The large variations of measured optical absorption spectra are traced back to the coexistence of magnetic orders (respectively, to the occupation of local orbitals). A consistent treatment of the Coulomb interaction indicates a partial cancellation of Coulomb parameters and supports the dominance of the electron-phonon coupling."],["dc.identifier.doi","10.1103/PhysRevB.95.235150"],["dc.identifier.eissn","2469-9969"],["dc.identifier.isi","000404468000001"],["dc.identifier.issn","2469-9950"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/75564"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-354"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation","SFB 1073: Kontrolle von Energiewandlung auf atomaren Skalen"],["dc.relation","SFB 1073 | Topical Area B | B02 Photonen-getriebener Energietransfer über Grenzflächen zwischen Materialien mit starken Korrelationen"],["dc.relation","SFB 1073 | Topical Area B | B03 Relaxation, Thermalisierung, Transport und Kondensation in hochangeregten Festkörpern"],["dc.relation","SFB 1073 | Topical Area C | C02 In situ hochauflösende Untersuchung des aktiven Zustands bei der photo- und elektrochemischen Wasserspaltung"],["dc.relation","SFB 1073 | Topical Area C | C03 Vom Elektronentransfer zur chemischen Energiespeicherung: ab-initio Untersuchungen korrelierter Prozesse"],["dc.relation.issn","2469-9969"],["dc.relation.issn","2469-9950"],["dc.relation.orgunit","Institut für Materialphysik"],["dc.title","Electronic structure of Pr1-xCaxMnO3"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]