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Auflistung Publikationen im Open Access gefördert durch die UB nach Auflistung nach Organisationseinheit "FB 07 - Mathematik und Informatik, Physik, Geographie"
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Item A Dry-Processed Al2O3/LiAlO2 Coating for Stabilizing the Cathode/Electrolyte Interface in High-Ni NCM-Based All-Solid-State Batteries(2022) Negi, Rajendra S.; Yusim, Yuriy; Pan, Ruijun; Ahmed, Shamail; Volz, Kerstin; Takata, Ryo; Schmidt, Franz; Henss, Anja; Elm, Matthias T.Item A fundamental problem of hypothesis testing with finite inventory in e-commerce(2020) Bohle, Dennis; Marynych, Alexander; Meiners, MatthiasItem A Sensitivity Assessment of COSMO-CLM to Different Land Cover Schemes in Convection-Permitting Climate Simulations over Europe(2021) Zhang, Mingyue; Tölle, Merja H.; Hartmann, Eva; Xoplaki, Eleni; Luterbacher, JürgItem A surface-enhanced Raman-spectroscopic study: Verification of the interparticle gap dependence of field enhancement by triangulation of spherical gold nanoparticle trimers(2019) Dort, Katharina; Kroth, Kathrin; Klar, Peter J.Item Ab initio calculations of conduction band effective mass parameters of thermoelectric Mg2X1-xYx (X, Y = Si, Ge, Sn) alloys(2020) Guerra-Castro, Juan Manuel; Mahr, Carsten; Giar, Marcel; Czerner, Michael; Heiliger, ChristianItem Ab initio description of disorder effects in layered cathode active materials by the coherent potential approximation(2022) Eckhardt, Janis K; Risius, Philipp E; Czerner, Michael; Heiliger, ChristianDisorder effects in alloys are usually modeled by averaging various supercell calculations considering different positions of the alloy atoms. This approach, however, is only possible as long as the portion of the individual components of the alloy is sufficiently large. Herein, we present an ab initio study considering the lithium insertion material Li1−x[Ni0.33Co0.33Mn0.33]O2 as model system to demonstrate the power of the coherent potential approximation within the Korringa–Kohn–Rostoker Green's function method. This approach enables the description of disorder effects within alloy systems of any composition. It is applied in this study to describe the (de-)intercalation of arbitrary amounts of lithium from the cathode active material. Moreover, we highlight that using either fully optimized structures or experimental lattice parameters and atomic positions both lead to comparable results. Our findings suggest that this approach is also suitable for modeling the electronic structure of state-of-the-art materials such as high-nickel alloys.Item Adsorption dynamics of bifunctional molecules: Allyl methyl ether on Si(001)(2021) Bohamud, Tamam; Höfer, Ulrich; Dürr, MichaelItem Advantageous optical characteristics of tantalum vanadium oxide as counter electrode in electrochromic devices(2022) Gies, Mario; Rempel, Thomas; Becker, Martin; Polity, AngelikaItem Assigning the absolute configuration of single aliphatic molecules by visual inspection(2018) Ebeling, Daniel; ekutor, Marina; Stiefermann, Marvin; Tschakert, Jalmar; Dahl, Jeremy E. P.; Carlson, Robert M. K.; Schirmeisen, André; Schreiner, Peter R.Deciphering absolute configuration of a single molecule by direct visual inspection is the next step in compound identification, with far-reaching implications for medicinal chemistry, pharmacology, and natural product synthesis. We demonstrate the feasibility of this approach utilizing low temperature atomic force microscopy (AFM) with a CO-functionalized tip to determine the absolute configuration and orientation of a single, adsorbed [123]tetramantane molecule, the smallest chiral diamondoid. We differentiate between single enantiomers on Cu(111) by direct visual inspection, and furthermore identify molecular dimers and molecular clusters. The experimental results are confirmed by a computational study that allowed quantification of the corresponding intermolecular interactions. The unique toolset of absolute configuration determination combined with AFM tip manipulation opens a route for studying molecular nucleation, including chirality-driven assembly or reaction mechanisms.Item Bond-specific fragmentation of oligopeptides via electronic stopping of swift heavy ions in molecular films(2022) Schneider, P.; Keller, P.; Schubert, I.; Bender, M.; Trautmann, C.; Dürr, M.Highly bond-specific fragmentation of oligopeptides induced by swift heavy ion (SHI) irradiation was investigated by means of mass spectrometry. In pronounced contrast to measurements of samples irradiated with keV ions, oligopeptides which were exposed to 946 MeV Au ions show a high abundance of specific fragments. The highly bond-specific nature of SHI-induced fragmentation is attributed to electronic stopping as the most relevant energy loss mechanism for SHI in the oligopeptide samples in combination with the subsequent coupling between the excited electronic and the atomic subsystem. Fragmentation induced by SHI is observed to be further influenced by the structure of the oligopeptides, suggesting that electronic excitation and/or the electronic-vibrational coupling depend on the details of the molecular structure.Item Characterization of Vegard strain related to exceptionally fast Cu-chemical diffusion in Cu2Mo6S8 by an advanced electrochemical strain microscopy method(2021) Badur, Sebastian; Renz, Diemo; Cronau, Marvin; Göddenhenrich, Thomas; Dietzel, Dirk; Roling, Bernhard; Schirmeisen, AndréItem Click Chemistry in Ultra-high Vacuum – Tetrazine Coupling with Methyl Enol Ether Covalently Linked to Si(001)(2021) Glaser, Timo; Meinecke, Jannick; Freund, Lukas; Länger, Christian; Luy, Jan-Niclas; Tonner, Ralf; Koert, Ulrich; Dürr, MichaelItem Combination of optical emission spectroscopy and multivariate data analysis techniques as a versatile non-invasive tool for characterizing xenon\/krypton mixed gas plasma inside operating ion thrusters(2022) Nauschütt, Benny; Chen, Limei; Holste, Kristof; Klar, Peter J.Non-invasive assessment of the plasma parameters is a useful tool for a reliable characterization of many electric thrusters for space applications. Due to high costs, limited availability, and growing use of electric propulsion in spaceflight, alternatives to Xe as a propellant are becoming increasingly important. One option is to use the lighter noble gas krypton or xenon/krypton gas mixtures as a propellant. We propose a versatile analytical approach for establishing empirical correlations between plasma parameters and optical emission (OE) spectroscopy utilizing principal component analysis (PCA). Our approach allows us to establish a surjective mapping of individual OE spectra via their PCA scores onto the corresponding plasma parameters. We prove the feasibility of this approach for Xe, Kr, and Xe/Kr mixed plasmas demonstrating that it is applicable for a wide range of propellant candidates. A major advantage is that the approach does not rely on any microscopic modeling of the OE spectra of the plasma. After having established corresponding reference mappings, the approach can be explored for determining non-invasively and spatially resolved plasma parameters of the propellant plasma of various kinds of operating ion thrusters, which operate in the same plasma regime as the reference plasma. Thus, this method may contribute to shorter qualification and testing times of ion thrusters.Item Combination of Thin-Layer Chromatography and Mass Spectrometry Using Cluster-Induced Desorption/Ionization.(2019) Heep, Julian; Tuchecker, Paul H. K.; Gebhardt, Christoph R.; Dürr, MichaelDesorption/ionization induced by neutral clusters (DINeC) was employed for mass spectrometry (MS) of oligopeptides and lipids after separation by means of thin-layer chromatography (TLC). Clear and fragmentation-free spectra were obtained from the TLC plates without any further sample treatment. Mass-resolved chromatograms were deduced when scanning the TLC plates with the cluster beam along the direction of solvent movement. Using vancomycin and noncovalently bound complexes, the soft nature of DINeC was demonstrated also when used in combination with TLC. As a test application, TLC and DINeC-MS were employed to separate and detect different phospholipids obtained from egg yolk.Item Combined XPS and DFT investigation of the adsorption modes of methyl enol ether functionalized cyclooctyne on Si(001)(2021) Glaser, Timo; Meinecke, Jannick; Länger, Christian; Luy, Jan-Niclas; Tonner, Ralf; Koert, Ulrich; Dürr, MichaelItem Comment on “Potential profile near the virtual cathode in presence of charged dust”(2020) Choudhary, MangilalItem Comparison of carrier-recombination in Ga(As,Bi)/Ga(N,As)-type-II quantum wells and W-type heterostructures(2021) Veletas, Julian; Hepp, Thilo; Dobener, Florian; Volz, Kerstin; Chatterjee, SangamItem Constructing covalent organic nanoarchitectures molecule by molecule via scanning probe manipulation(2021) Zhong, Qigang; Ihle, Alexander; Ahles, Sebastian; Wegner, Hermann A.; Schirmeisen, Andre; Ebeling, DanielItem Construction and use of rock-cut cisterns: a chronological OSL approach in the arid Negev Highlands, Israel(2021) Junge, Andrea; Dunseth, Zachary C.; Shahack-Gross, Ruth; Finkelstein, Israel; Fuchs, MarkusItem Correlation between Surface Reactions and Electrochemical Performance of Al2O3- and CeO2-Coated NCM Thin Film Cathodes(2023) Hemmelmann, Hendrik; Ruess, Raffael; Klement, Philip; Schörmann, Jörg; Chatterjee, Sangam; Sann, Joachim; Elm, Matthias T.Depositing ultrathin oxide coatings has been proven a successful approach to stabilize the surface of LiNixCoyMnzO2 active cathode material in lithium-ion batteries (LIB). The beneficial effect of Al2O3 coatings arises at least partly from spontaneous reactions between coating and liquid electrolyte. However, it remains unclear if comparable surface reactions occur for other oxide coatings. One difficulty is the characterization of reaction products at the cathode–electrolyte interface due to the multi-phase properties of composite cathodes. Here, thin films are utilized as model systems to correlate surface reactions with the performance of Al2O3- and CeO2-coated nickel cobalt manganese oxides (NCM). Electrochemical characterization confirms that an Al2O3 coating improves long-term cycling stability, while CeO2-coated thin films perform even worse than uncoated counterparts. The analysis of the surface reaction products using X-ray photoelectron spectroscopy shows that both coatings are fluorinated upon contact with liquid electrolyte in agreement with thermodynamic considerations. The fluorinated Al2O3 coating is stable during cycling, resulting in the improved cell performance. In contrast, the fluorinated CeO2 coating changes chemical composition, facilitating corrosion of the NCM surface. The results demonstrate the importance of a detailed analysis of surface reactions to evaluate the suitability of ultrathin oxide layers as protective coatings for LIBs.