@misc{EhrlingSenkovskaEfimovaetal., author = {Ehrling, Sebastian and Senkovska, Irena and Efimova, Anastasia and Bon, Volodymyr and Abylgazina, Leila and Petkov, Petko and Evans, Jack D. and Attallah, Ahmed Gamal and Wharmby, Michael Thomas and Roslova, Maria and Huang, Zhehao and Tanaka, Hideki and Wagner, Andreas and Schmidt, Peer and Kaskel, Stefan}, title = {Temperature Driven Transformation of the Flexible Metal-Organic Framework DUT-8(Ni)}, series = {Chemistry - a European journal}, volume = {28}, journal = {Chemistry - a European journal}, number = {55}, issn = {1521-3765}, doi = {10.1002/chem.202201281}, pages = {1 -- 10}, abstract = {DUT-8(Ni) metal-organic framework belongs to the family of flexible pillared layer materials. The desolvated framework can be obtained in the open pore form (op) or in the closed pore form (cp), depending on the crystal size regime. In the present work, we report on the behaviour of desolvated DUT-8(Ni) at elevated temperatures. For both, op and cp variants, heating causes a structural transition, leading to an new, crystalline compound, containing two interpenetrated networks. The state of the framework before transition (op vs. cp) influences the transition temperature: the small particles of the op phase transform at significantly lower temperature in comparison to the macroparticles of the cp phase, transforming close to the decomposition temperature. The new compound, confined closed pore phase (ccp), was characterized by powder X-ray diffraction and spectroscopic techniques, such as IR, EXAFS, and positron annihilation lifetime spectroscopy (PALS). Thermal effects of structural cp to ccp transitions were studied using differential scanning calorimetry (DSC), showing an overall exothermic effect of the process, involving bond breaking and reformation. Theoretical calculations reveal the energetics, driving the observed temperature induced phase transition.}, language = {en} } @misc{MedinaMendezFistlerOevermannetal., author = {Medina M{\´e}ndez, Juan Ali and Fistler, Marco and Oevermann, Michael and Schmidt, Heiko and Riebel, Ulrich}, title = {Economical map-based turbulence models: Developments and perspectives for the numerical analysis of electrostatic precipitation}, series = {Book of Abstracts PARTEC International Congress on Particle Technology, September 26-28, 2023, N{\"u}rnberg}, journal = {Book of Abstracts PARTEC International Congress on Particle Technology, September 26-28, 2023, N{\"u}rnberg}, publisher = {VDI Verlag GmbH}, address = {D{\"u}sseldorf}, pages = {634 -- 638}, language = {en} } @misc{MatthiesBeerBoecheretal., author = {Matthies, Ellen and Beer, Katrin and B{\"o}cher, Michael and Sundmacher, Kai and K{\"o}nig-Mattern, Laura and Arlinghaus, Julia and Bl{\"o}baum, Anke and Jaeger-Erben, Melanie and Schmidt, Karolin}, title = {Framework conditions for the transformation toward a sustainable carbon-based chemical industry - A critical review of existing and potential contributions from the social sciences}, series = {Journal of Cleaner Production}, volume = {470 (2024)}, journal = {Journal of Cleaner Production}, publisher = {Elsevier BV}, issn = {0959-6526}, doi = {10.1016/j.jclepro.2024.143279}, pages = {1 -- 13}, language = {en} } @misc{TschammerBussPożarowskaetal., author = {Tschammer, Rudi and Buß, Lars and Pożarowska, Emilia and Morales, Carlos and Senanayake, Sanjaya D. and Prieto, Mauricio J. and Tănase, Liviu C. and de Souza Caldas, Lucas and Tiwari, Aarti and Schmidt, Thomas and Ni{\~n}o, Miguel A. and Foerster, Michael and Falta, Jens and Flege, Jan Ingo}, title = {High-temperature growth of CeOx on Au(111) and behavior under reducing and oxidizing conditions}, series = {The journal of physical chemistry C}, volume = {129}, journal = {The journal of physical chemistry C}, number = {7}, publisher = {American Chemical Society (ACS)}, address = {Washington, DC}, issn = {1932-7447}, doi = {10.1021/acs.jpcc.4c08072}, pages = {3583 -- 3594}, abstract = {Inverse oxide-metal model catalysts can show superior activity and selectivity compared with the traditional supported metal-oxide architecture, commonly attributed to the synergistic overlayer-support interaction. We have investigated the growth and redox properties of ceria nanoislands grown on Au(111) between 700 and 890 °C, which yields the CeO2-Au(111) model catalyst system. We have observed a distinct correlation between deposition temperature, structural order, and oxide composition through low-energy electron microscopy, low-energy electron diffraction, intensity-voltage curves, and X-ray absorption spectroscopy. Improved structural order and thermal stability of the oxide have been achieved by increasing the oxygen chemical potential at the substrate surface using reactive oxygen (O/O2) instead of molecular O2 during growth. In situ characterization under reducing (H2) and oxidizing atmospheres (O2, CO2) indicates an irreversible loss of structural order and redox activity at high reduction temperatures, while moderate temperatures result in partial decomposition of the ceria nanoislands (Ce3+/Ce4+) to metallic cerium (Ce0). The weak interaction between Au(111) and CeOx would facilitate its reduction to the Ce0 metallic state, especially considering the comparatively strong interaction between Ce0 and Au0. Besides, the higher reactivity of atomic oxygen promotes a stronger interaction between the gold and oxide islands during the nucleation process, explaining the improved stability. Thus, we propose that by driving the nucleation and growth of the ceria/Au system in a highly oxidizing regime, novel chemical properties can be obtained.}, language = {en} } @misc{VeldkampSchmidtMarkwitzetal., author = {Veldkamp, Edzo and Schmidt, Marcus and Markwitz, Christian and Beule, Lukas and Beuschel, Ren{\´e} and Biert{\"u}mpfel, Andrea and Bischel, Xenia and Duan, Xiaohong and Gerjets, Rowena and G{\"o}bel, Leonie and Graß, R{\"u}diger and Guerra, Victor and Heinlein, Florian and Komainda, Martin and Langhof, Maren and Luo, Jie and Potthoff, Martin and Ramshorst, Justus G. V. van and Rudolf, Carolin and Seserman, Diana-Maria and Shao, Guodong and Siebicke, Lukas and Svoboda, Nikolai and Swieter, Anita and Carminati, Andrea and Freese, Dirk and Graf, Torsten and Greef, J{\"o}rg M. and Isselstein, Johannes and Jansen, Martin and Karlovsky, Petr and Knohl, Alexander and Lamersdorf, Norbert and Priesack, Eckart and Wachendorf, Christine and Wachendorf, Michael and Corre, Marife D.}, title = {Multifunctionality of temperate alley-cropping agroforestry outperforms open cropland and grassland}, series = {Communications Earth \& Environment}, volume = {4}, journal = {Communications Earth \& Environment}, number = {1}, publisher = {Springer Science and Business Media LLC}, issn = {2662-4435}, doi = {10.1038/s43247-023-00680-1}, pages = {10}, abstract = {AbstractIntensively managed open croplands are highly productive but often have deleterious environmental impacts. Temperate agroforestry potentially improves ecosystem functions, although comprehensive analysis is lacking. Here, we measured primary data on 47 indicators of seven ecosystem functions in croplands and 16 indicators of four ecosystem functions in grasslands to assess how alley-cropping agroforestry performs compared to open cropland and grassland. Carbon sequestration, habitat for soil biological activity, and wind erosion resistance improved for cropland agroforestry (P ≤ 0.03) whereas only carbon sequestration improved for grassland agroforestry (P \< 0.01). In cropland agroforestry, soil nutrient cycling, soil greenhouse gas abatement, and water regulation did not improve, due to customary high fertilization rates. Alley-cropping agroforestry increased multifunctionality, compared to open croplands. To ameliorate the environmental benefits of agroforestry, more efficient use of nutrients is required. Financial incentives should focus on conversion of open croplands to alley-cropping agroforestry and incorporate fertilizer management.}, language = {en} } @misc{LuckeSchmidtAlSaadetal., author = {Lucke, Bernhard and Schmidt, Michael and Al-Saad, Ziad and H{\"u}ttl, Reinhard F. and Bens, Oliver}, title = {The abandonment of the Decapolis region in Northern Jordan - forced by environmental change?}, series = {Quaternary International}, volume = {135}, journal = {Quaternary International}, number = {1}, issn = {1040-6182}, pages = {65 -- 81}, language = {en} } @misc{BalasUrbankKadenetal., author = {Balas, Johannes and Urbank, Christian and Kaden, Peter and Patzschke, Michael and M{\"a}rz, Juliane and Kvashnina, Kristina O. and Schmidt, Moritz and Stumpf, Thorsten and Gericke, Robert}, title = {Bonding trends in pyridine-2-thiolato complexes of tetravalent actinides}, series = {Inorganic chemistry}, volume = {64}, journal = {Inorganic chemistry}, number = {44}, publisher = {American Chemical Society}, address = {Washington, DC}, issn = {1520-510X}, doi = {10.1021/acs.inorgchem.5c03369}, pages = {21919 -- 21931}, abstract = {Complexes of tetravalent actinides (An: Th, U, Np, Pu) with the bidentate (N,S)-donor ligand pyridine-2-thiolate (2-PyS, PyS-) were synthesized in 1:4 or 1:5 ratios. This includes the first structurally characterized Np complex with (N,S)-donor ligands, filling a notable gap in An coordination chemistry. An improved synthetic approach with PyS-SiMe3 enabled efficient formation of the 1:4 complexes in THF as coordinating solvent. The compounds were comprehensively characterized in solution and in solid phase, supported by quantum chemical calculations. Experimental and theoretical results show matching trends in the binding behavior of AnIV. The covalent bond contributions in An-N and An-S bonding increase along the series of An from Th to Pu. The bonds to the soft sulfur donors consistently have the highest covalent contributions with a remarkably high percentage for Pu-S (IQA analysis: >34\%) over the harder N donors or An-O bonds of coordinating THF. High-resolution X-ray absorption and infrared spectroscopy indicate similar electronic and structural properties across AnIV complexes, while SQUID magnetometry uncovered significant differences in magnetic behavior at low temperatures depending on the complex compositions. This work advances the understanding of An-ligand bonding, emphasizing covalency and electronic structures, and expands fundamental insights into An chemistry.}, language = {en} } @techreport{SchmidtGieseHeinemannetal., author = {Schmidt, Peer and Giese, Marie and Heinemann, Robert and Nawdiyal, Amruta and Knorr, Monika and Breitkopf, Cornelia and Schneegans, Marcel Felix and Pinnau, Sebastian and Lorenz, Tommy and Mickoleit, Erik and to Baben, Moritz and Keuter, Philipp and M{\"u}ller, Michael and Sergeev, Dmitry and Ewaznezhad Fard, Darya and Morsa, Amedeo and Rhys, Dominic Jacob and Yazhenskikh, Elena}, title = {PCM-Screening-2 : Evaluierung eutektischer Gemische f{\"u}r den Einsatz als PCM : thermodynamische Modellierung und experimentelle Methoden - 2}, series = {Deutsche Forschungsberichte}, journal = {Deutsche Forschungsberichte}, doi = {10.34657/28504}, pages = {182}, abstract = {Durch den Einsatz von W{\"a}rme- und K{\"a}ltespeichern in Geb{\"a}uden, Industrieanlagen und Kraftwerken k{\"o}nnen Lastschwankungen reduziert und die Anlageneffizienz verbessert werden. Latentw{\"a}rmespeicher (PCM) erm{\"o}glichen durch Ausnutzung einer fest-fl{\"u}ssig Phasenumwandlung hohe Speicherdichten bei geringen Temperaturdifferenzen. Die Verf{\"u}gbarkeit geeigneter und kosteng{\"u}nstiger PCM's ist derzeit noch eingeschr{\"a}nkt. Ein Screening geeigneter Stoffsysteme zur Bildung multin{\"a}rer Eutektika durch thermodynamische Modellierung der Phasengleichgewichte erlaubt fundierte Vorhersagen zur Zusammensetzung eutektischer Gemische, ihren Schmelztemperaturen und -enthalpien. Auf Basis der Literatur, umfangreicher experimenteller Untersuchungen und Simulationen wurde im Projekt eine im Temperaturbereich nicht eingeschr{\"a}nkte thermochemische Datenbank f{\"u}r das komplexe Stoffsystem Na+, K+, Ca2+, Mg2+ // Cl-, NO3-, SO4_2-, CO3_2- // H2O geschaffen, die eine Auswahl neuer PCM mit optimalen thermodynamischen Eigenschaften f{\"u}r spezifische Prozessanforderungen auf Basis von in Deutschland in großen Mengen verf{\"u}gbaren, preiswerten Rohstoffen erm{\"o}glicht. Weiterhin wurde ein CalPhaD-basiertes Viskosit{\"a}tsmodell, ein Screening-Verfahren inkl. Webserver und intuitive Visualisierungsm{\"o}glichkeiten hochkomponentiger Systeme entwickelt. Mittels eines Screenings erfolgte eine Vorauswahl von potentiell als PCM geeigneten Gemischen, die umfangreich charakterisiert wurden. Auf Basis der vielversprechenden Speicherdichten und der niedrigen Materialkosten wird erwartet, dass ein oder mehrere dieser identifizierten PCMs in die Anwendung als thermische Speicher gebracht werden k{\"o}nnen.}, language = {de} } @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} }