@misc{SchmeisserSchmidtSeiboldetal., author = {Schmeißer, Dieter and Schmidt, Stephan and Seibold, G{\"o}tz and Cherkashinin, Gennady and Jaegermann, Wolfram}, title = {Localized Gap States in LiCoO2 and their Influence on the Transport Properties in Li-Ion Batteries}, series = {ECS Transactions}, volume = {25}, journal = {ECS Transactions}, number = {35}, issn = {1938-5862}, pages = {37 -- 45}, language = {en} } @misc{SchmidtSchmeisser, author = {Schmidt, Stephan and Schmeißer, Dieter}, title = {Electronic structure of cobalt-nickel mixed oxides}, series = {Solid State Ionics}, journal = {Solid State Ionics}, number = {225}, issn = {1872-7689}, doi = {10.1016/j.ssi.2012.06.009}, pages = {737 -- 741}, abstract = {We investigate the electronic structure of cobalt-nickel mixed oxides by means of SR-based electron spectroscopy. We vary the Co-Ni content systematically and find that the most significant changes in the spectroscopic data occur at a mixing ratio of 30/70. We analyze the electronic structure of this material in detail and we are able to distinguish between pure covalent contributions, which cause a band gap of about 6 eV and empty defect states, whichfill the band gap almost completely. These defects are associated with the formation of 3d7L charge transfer states. These are correlated defect states and are identified by resonant photo-emission spectroscopy.}, language = {en} } @inproceedings{SchmidtSchmeisser, author = {Schmidt, Stephan and Schmeißer, Dieter}, title = {Cobalt/nickel mixed oxides - cathode materials for Li-Ion-Batteries}, series = {Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 45}, booktitle = {Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 45}, publisher = {Deutsche Physikalische Gesellschaft}, address = {Bad Honnef}, issn = {0420-0195}, pages = {S. 596}, abstract = {Replacing Co by large amounts of Ni is considered to reduce costs in Li-Ion-Batteries while maintaining their performance. We are interested in whether this replacement causes changes in the valence band (VB) and conduction band (CB) states or not. Samples were prepared as thin films from nitrate solutions on metal substrates and annealed in air and UHV. The Co to Ni ratio was varied from 50/50 over 40/60 and 30/70 up to 20/80. The results are compared to the pure Co-oxide. Experiments were carried out at the U49/2 beamline at BESSYII, Berlin. XPS of the TM2p states reveals the existence of charge transfer ground states and different oxidation states. NEXAS at the Co2p, Ni2p and O1s edges projects the density of unoccupied states while resonant PES at these edges provides the related partial density of states (pDOS) and thus can be used to distinguish between the different contributions of TM3d and O2p states in the valence band region. We find systematic variation of the VB structure, the valence band maximum and a shift at the O1s absorption edge while the TM2p XPS and absorption spectra do not seem to be affected by the mixing.}, language = {en} } @misc{JahnBlaudeckBaumannetal., author = {Jahn, Stephan F. and Blaudeck, Thomas and Baumann, Reinhard R. and Jakob, Alexander and Ecorchard, Petra and R{\"u}ffer, Tobias and Lang, Heinrich and Schmidt, Peer}, title = {Inkjet Printing of Conductive Silver Patterns by Using the First Aqueous Particle-Free MOD Ink without Additional Stabilizing Ligands}, series = {Chemistry of Materials}, volume = {22}, journal = {Chemistry of Materials}, number = {10}, issn = {1520-5002}, doi = {10.1021/cm9036428}, pages = {3067 -- 3071}, abstract = {The chemical and physical properties of [AgO2C(CH2OCH2)3H] (3) and its use as an aqueous, ligand-free MOD ink (MOD = metal-organic decomposition) for piezo inkjet printing is discussed. The printed, thermal, or photochemical sintered silver features are electrically conductive on glass (2.7 × 107 S m-1) and PET (PET = polyethylene terephthalate) substrates (1.1 × 107 S m-1) corresponding to 43\% and 18\% of the bulk silver conductivity. Conducted tape tests show the suitability of the ink for particularly polymer substrates. TG-MS studies demonstrate a two-step decomposition for the conversion of 3 to elemental silver. The structure of 3 in the solid state was determined by single X-ray structure determination.}, language = {en} } @misc{JahnJakobBlaudecketal., author = {Jahn, Stephan F. and Jakob, Alexander and Blaudeck, Thomas and Schmidt, Peer and Lang, Heinrich and Baumann, Reinhard R.}, title = {Inkjet printing of conductive patterns with an aqueous solution of [AgO2C(CH2OCH2)3H] without any additional stabilizing ligands}, series = {Thin Solid Films}, volume = {518}, journal = {Thin Solid Films}, number = {12}, issn = {0040-6090}, doi = {10.1016/j.tsf.2010.01.030}, pages = {3218 -- 3222}, abstract = {The use of silver(I)-2-[2-(2-methoxyethoxy)ethoxy]acetate, [AgO2C(CH2OCH2)3H], and its application as an aqueous metal-organic decomposition (MOD) inkjet ink is reported. The chemical and physical properties of the silver carboxylate and the ink formulated thereof are discussed. The ink meets all requirements of piezo driven inkjet printing. The printed features were converted into electrically conducting silver patterns by thermal or photo-thermal treatment. The conversion of [AgO2C(CH2OCH2)3H] to elemental silver follows a two-step decomposition as demonstrated by thermogravimetry-mass spectrometry (TG-MS) measurements. The measured conductivities of the printed features on glass and polyethylene-terephthalate (PET) are 2.7 × 107 S m-1 and 1.1 × 107 S m-1, respectively, which correspond to 43\% (glass) and 18\% (PET) of the bulk silver conductivity.}, language = {en} } @misc{BusseFischerGebaueretal., author = {Busse, Ralph-Peter and Fischer, Gert and Gebauer, Gert and H{\"o}fler, Frank and Junker, Sabine and Kramer, Thomas and Opperskalski, Stephan and Potthoff, Ulrich and Remus, Ricardo and Schlamkow, Christian and Schmidt, Wolfgang and Scobel, Ekkehard and Stopp, Horst and Strangfeld, Peter and Trang, Ngyen Thi Thu and V{\"o}lker, Eduard and Vukorep, Ilija and Weidhase, Frieder and Winzer, Reinhard}, title = {Floating Architecture - Construction on and near water}, editor = {Stopp, Horst and Strangfeld, Peter}, publisher = {LIT-Verlag}, address = {Berlin}, isbn = {978-3-643-90910-7}, pages = {134}, abstract = {The publishers are receiving more and more inquiries about the topic "Floating Architecture", particularly about technical details, water chemistry, as well as ice and wave problems. Since there is a lack of technical literature on this topic, most students working on projects or theses related to this topic send their inquiries. A time of general and quick changes results in a large number of daily publications. Therefore it is difficult to understand why there is a lack of lit-erature about floating structures. One has to consider that sea levels will continue to rise and consequently a larger number of people will have to live on the surface of the sea. Obviously, some expert knowledge is required which needs a longer period of time to be gained through scientific advancements and experience. The publishers, who have been dealing with the topic of floating houses for some years, are grateful to the authors for their agreement to allow the publication of their papers on floating architecture. These papers were mainly prepared for two conferences on floating architecture held in the study centre of the IBA building, Großr{\"a}schen. Therefore, the reader should know that, along with the usual papers, only a selection of self-explaining transparencies is shown in order to meet the printing requirements. The included list of both the authors and their addresses makes it easy for interested people to send any inquiries to them. A short introduction as well as an outlook at the end of each paper is meant to draw attention to current events in order to be able to promptly identify opportunities and risks connected with living on the water.}, language = {en} } @misc{WachsmuthHerrmannHerzogetal., author = {Wachsmuth, Gerd and Herrmann, Marc and Herzog, Roland and Schmidt, Stephan and Vidal-N{\´u}{\~n}ez, Jos{\´e}}, title = {Discrete Total Variation with Finite Elements and Applications to Imaging}, series = {Journal of Mathematical Imaging and Vision : (JMIV)}, volume = {61}, journal = {Journal of Mathematical Imaging and Vision : (JMIV)}, number = {4}, issn = {0924-9907}, doi = {10.1007/s10851-018-0852-7}, pages = {411 -- 431}, abstract = {The total variation (TV)-seminorm is considered for piecewise polynomial, globally discontinuous (DG) and continuous (CG) finite element functions on simplicial meshes. A novel, discrete variant (DTV) based on a nodal quadrature formula is defined. DTV has favorable properties, compared to the original TV-seminorm for finite element functions. These include a convenient dual representation in terms of the supremum over the space of Raviart-Thomas finite element functions, subject to a set of simple constraints. It can therefore be shown that a variety of algorithms for classical image reconstruction problems, including TV-L2 and TV-L1, can be implemented in low and higher-order finite element spaces with the same efficiency as their counterparts originally developed for images on Cartesian grids.}, language = {en} } @misc{BoelteUtgenanntSchmidtetal., author = {B{\"o}lte, Jens-Henning and Utgenannt, Stephan and Schmidt, Max and Klepel, Olaf and Bron, Michael and Rokicińska, Anna and Jarczewski, Sebastian and Kuśtrowski, Piotr}, title = {S-doped and N+S-co-doped carbon catalysts in redox reactions}, series = {Microporous and mesoporous materials}, volume = {407}, journal = {Microporous and mesoporous materials}, publisher = {Elsevier BV}, address = {Amsterdam}, issn = {1873-3093}, doi = {10.1016/j.micromeso.2026.114129}, pages = {1 -- 11}, abstract = {In this contribution, the effects of heteroatom doping of porous carbon materials with S and N on their ability to catalyze redox-reactions involving the activation of molecular oxygen were investigated. For this purpose, a library of in total 54 undoped, S-doped and N + S-co-doped porous carbons was obtained via a template-based synthesis procedure using mesoporous silica gel as the template. To understand the influence of S on the properties of the doped carbons three different S-containing precursors, namely dimethyl sulfoxide (DMSO), p-toluene sulfonic acid and thiophene, were used. In order to investigate possible synergistic effects of S- and N-co-doping, urea was employed as the sole N-containing precursor. The obtained carbon catalysts were characterized by selected methods such as N2-physisorption at 77 K, X-ray diffraction (XRD), Raman spectroscopy, elemental analysis and X-ray photoelectron spectroscopy (XPS). Each carbon catalyst was tested in the oxidation of sulfurous acid (OSA) to sulfuric acid, the electrochemical oxygen reduction (ORR) and the oxidative dehydrogenation (ODH) of ethylbenzene. Owing to the similar textural and structural properties achieved through template-based synthesis of the carbon catalyst library, the results of the catalytic redox-reactions could directly be related to the respective heteroatom dopant. The observed trends indicate that in these redox-reactions S-species behave somewhat similar to O-species bound on the carbon surface. Furthermore, it can be shown that N + S co-doping rather combines the positive and negative effects of the individual dopants on the activity, than creating a synergistic effect that surpasses the individual contribution.}, language = {en} }