--- _id: '63950' abstract: - lang: eng text: Sodium-ion batteries are at the forefront of new, sustainable energy systems required for the global energy transition. 23Na in situ solid-state nuclear magnetic resonance spectroscopy is capable of unraveling structures in working electrochemical cells during the charging and discharging processes. To evaluate its suitability for long-term studies, local sodium environments in sodium/sodium ion cells based on silicon carbonitride and hard carbon materials are tracked for up to 49 cycles (228.5?h). The formation of dendrites as well as the decay of a secondary metallic sodium species is observed, and local structures are analyzed up to the point of capacity degradation and cell failure. Initial points of cell breakdown are reflected in the NMR data by characteristic changes in signal intensities, whereas the degradation of the cells is reflected by a cease to periodic signal intensity fluctuations. Meanwhile, ex situ 23Na NMR spectra of the deactivated cells reveal a complex range of environments for sodium ions. author: - first_name: Sonja full_name: Egert, Sonja last_name: Egert - first_name: Renuka full_name: Remesh, Renuka last_name: Remesh - first_name: Agatha Clarissa full_name: Jusdi, Agatha Clarissa last_name: Jusdi - first_name: Yushi full_name: Sugawara, Yushi last_name: Sugawara - first_name: Konstantin full_name: Schutjajew, Konstantin last_name: Schutjajew - first_name: Martin full_name: Oschatz, Martin last_name: Oschatz - first_name: Gerd full_name: Buntkowsky, Gerd last_name: Buntkowsky - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann citation: ama: Egert S, Remesh R, Jusdi AC, et al. Long-Term Cycling Stability of Sodium/Sodium Ion Cells Probed by In Situ Solid-State NMR Spectroscopy. Batteries & Supercaps. 2025;n/a(n/a):e202500516. doi:10.1002/batt.202500516 apa: Egert, S., Remesh, R., Jusdi, A. C., Sugawara, Y., Schutjajew, K., Oschatz, M., Buntkowsky, G., & Gutmann, T. (2025). Long-Term Cycling Stability of Sodium/Sodium Ion Cells Probed by In Situ Solid-State NMR Spectroscopy. Batteries & Supercaps, n/a(n/a), e202500516. https://doi.org/10.1002/batt.202500516 bibtex: '@article{Egert_Remesh_Jusdi_Sugawara_Schutjajew_Oschatz_Buntkowsky_Gutmann_2025, title={Long-Term Cycling Stability of Sodium/Sodium Ion Cells Probed by In Situ Solid-State NMR Spectroscopy}, volume={n/a}, DOI={10.1002/batt.202500516}, number={n/a}, journal={Batteries & Supercaps}, publisher={John Wiley & Sons, Ltd}, author={Egert, Sonja and Remesh, Renuka and Jusdi, Agatha Clarissa and Sugawara, Yushi and Schutjajew, Konstantin and Oschatz, Martin and Buntkowsky, Gerd and Gutmann, Torsten}, year={2025}, pages={e202500516} }' chicago: 'Egert, Sonja, Renuka Remesh, Agatha Clarissa Jusdi, Yushi Sugawara, Konstantin Schutjajew, Martin Oschatz, Gerd Buntkowsky, and Torsten Gutmann. “Long-Term Cycling Stability of Sodium/Sodium Ion Cells Probed by In Situ Solid-State NMR Spectroscopy.” Batteries & Supercaps n/a, no. n/a (2025): e202500516. https://doi.org/10.1002/batt.202500516.' ieee: 'S. Egert et al., “Long-Term Cycling Stability of Sodium/Sodium Ion Cells Probed by In Situ Solid-State NMR Spectroscopy,” Batteries & Supercaps, vol. n/a, no. n/a, p. e202500516, 2025, doi: 10.1002/batt.202500516.' mla: Egert, Sonja, et al. “Long-Term Cycling Stability of Sodium/Sodium Ion Cells Probed by In Situ Solid-State NMR Spectroscopy.” Batteries & Supercaps, vol. n/a, no. n/a, John Wiley & Sons, Ltd, 2025, p. e202500516, doi:10.1002/batt.202500516. short: S. Egert, R. Remesh, A.C. Jusdi, Y. Sugawara, K. Schutjajew, M. Oschatz, G. Buntkowsky, T. Gutmann, Batteries & Supercaps n/a (2025) e202500516. date_created: 2026-02-07T09:13:59Z date_updated: 2026-02-17T16:18:23Z doi: 10.1002/batt.202500516 extern: '1' issue: n/a keyword: - solid-state nmr - hard carbon - in-situ - SiCN - sodium ion batteries language: - iso: eng page: e202500516 publication: Batteries & Supercaps publisher: John Wiley & Sons, Ltd status: public title: Long-Term Cycling Stability of Sodium/Sodium Ion Cells Probed by In Situ Solid-State NMR Spectroscopy type: journal_article user_id: '100715' volume: n/a year: '2025' ... --- _id: '64062' abstract: - lang: eng text: Abstract Novel SBA-15-supported heterogeneous catalysts are synthesized and applied in the Mizoroki?Heck and the Suzuki?Miyaura cross-coupling reactions in green solvents like PEG or water. The structural properties of the products after each synthesis step are monitored by different analytics. The amount of amine/carboxyl groups and vanillin/histidine methyl ester and thermal stability are determined by TGA and elemental analysis, while ICP-OES delivered the amount of palladium of the catalysts. The morphology is investigated by SEM and XPS and confirms the presence of coordinated palladium in the zero-oxidation state. Gas adsorption analysis is conducted, which indicates the presence of palladium clusters in one of the two catalysts, which is underlined by BSE images combined with EDX. A detailed 13C ssNMR and DNP-enhanced 15N ssNMR spectral analysis is presented, which provides ultimate proof of the successful syntheses of the catalysts. The coordination of the palladium onto the carrier material is shown by combining the NMR spectral results with the results of the other analytics. First catalytic tests show for the Mizoroki?Heck reaction yields up to nearly 100% and for the Suzuki-Miyaura up to 88% in the presence of PEG and water, respectively. author: - first_name: Till full_name: Wissel, Till last_name: Wissel - first_name: Lorenz full_name: Rösler, Lorenz last_name: Rösler - first_name: Martin full_name: Brodrecht, Martin last_name: Brodrecht - first_name: Mark V. full_name: Höfler, Mark V. last_name: Höfler - first_name: Kevin full_name: Herr, Kevin last_name: Herr - first_name: Marcos full_name: Oliveira Jr., Marcos last_name: Oliveira Jr. - first_name: Vytautas full_name: Klimavicius, Vytautas last_name: Klimavicius - first_name: Martin full_name: Ebert, Martin last_name: Ebert - first_name: Hergen full_name: Breitzke, Hergen last_name: Breitzke - first_name: Markus full_name: Hoffmann, Markus last_name: Hoffmann - first_name: Gerd full_name: Buntkowsky, Gerd last_name: Buntkowsky - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann citation: ama: 'Wissel T, Rösler L, Brodrecht M, et al. Novel Heterogeneous Pd Catalysts for Cross-Coupling Reactions in Biocompatible Media: Structural Insights from Solid-State NMR Techniques. ChemCatChem. 2024;17:e202401511. doi:10.1002/cctc.202401511' apa: 'Wissel, T., Rösler, L., Brodrecht, M., Höfler, M. V., Herr, K., Oliveira Jr., M., Klimavicius, V., Ebert, M., Breitzke, H., Hoffmann, M., Buntkowsky, G., & Gutmann, T. (2024). Novel Heterogeneous Pd Catalysts for Cross-Coupling Reactions in Biocompatible Media: Structural Insights from Solid-State NMR Techniques. ChemCatChem, 17, e202401511. https://doi.org/10.1002/cctc.202401511' bibtex: '@article{Wissel_Rösler_Brodrecht_Höfler_Herr_Oliveira Jr._Klimavicius_Ebert_Breitzke_Hoffmann_et al._2024, title={Novel Heterogeneous Pd Catalysts for Cross-Coupling Reactions in Biocompatible Media: Structural Insights from Solid-State NMR Techniques}, volume={17}, DOI={10.1002/cctc.202401511}, journal={ChemCatChem}, publisher={John Wiley & Sons, Ltd}, author={Wissel, Till and Rösler, Lorenz and Brodrecht, Martin and Höfler, Mark V. and Herr, Kevin and Oliveira Jr., Marcos and Klimavicius, Vytautas and Ebert, Martin and Breitzke, Hergen and Hoffmann, Markus and et al.}, year={2024}, pages={e202401511} }' chicago: 'Wissel, Till, Lorenz Rösler, Martin Brodrecht, Mark V. Höfler, Kevin Herr, Marcos Oliveira Jr., Vytautas Klimavicius, et al. “Novel Heterogeneous Pd Catalysts for Cross-Coupling Reactions in Biocompatible Media: Structural Insights from Solid-State NMR Techniques.” ChemCatChem 17 (2024): e202401511. https://doi.org/10.1002/cctc.202401511.' ieee: 'T. Wissel et al., “Novel Heterogeneous Pd Catalysts for Cross-Coupling Reactions in Biocompatible Media: Structural Insights from Solid-State NMR Techniques,” ChemCatChem, vol. 17, p. e202401511, 2024, doi: 10.1002/cctc.202401511.' mla: 'Wissel, Till, et al. “Novel Heterogeneous Pd Catalysts for Cross-Coupling Reactions in Biocompatible Media: Structural Insights from Solid-State NMR Techniques.” ChemCatChem, vol. 17, John Wiley & Sons, Ltd, 2024, p. e202401511, doi:10.1002/cctc.202401511.' short: T. Wissel, L. Rösler, M. Brodrecht, M.V. Höfler, K. Herr, M. Oliveira Jr., V. Klimavicius, M. Ebert, H. Breitzke, M. Hoffmann, G. Buntkowsky, T. Gutmann, ChemCatChem 17 (2024) e202401511. date_created: 2026-02-07T16:18:53Z date_updated: 2026-02-17T16:12:41Z doi: 10.1002/cctc.202401511 extern: '1' intvolume: ' 17' keyword: - SBA-15 - Heterogeneous catalyst - Pd cross-coupling - Polyethylene glycol - Solid-state DNP NMR language: - iso: eng page: e202401511 publication: ChemCatChem publication_identifier: issn: - 1867-3880 publisher: John Wiley & Sons, Ltd status: public title: 'Novel Heterogeneous Pd Catalysts for Cross-Coupling Reactions in Biocompatible Media: Structural Insights from Solid-State NMR Techniques' type: journal_article user_id: '100715' volume: 17 year: '2024' ... --- _id: '63988' abstract: - lang: eng text: This concept summarizes recent advances in development and application of DNP enhanced multinuclear solid-state NMR to study the molecular structure and surface functionalization of cellulose and paper-based materials. Moreover, a novel application is presented where DNP enhanced 13C and 15N solid-state NMR is used to identify structure moieties formed by cross-linking of hydroxypropyl cellulose. Given these two aspects of this concept-type of article, we thus combine both, a review on recent findings already published and unpublished recent data that complement the existing knowledge in the field of characterization of functional lignocellulosic materials by DNP enhanced solid-state NMR. author: - first_name: Mark V. full_name: Höfler, Mark V. last_name: Höfler - first_name: Jonas full_name: Lins, Jonas last_name: Lins - first_name: David full_name: Seelinger, David last_name: Seelinger - first_name: Lukas full_name: Pachernegg, Lukas last_name: Pachernegg - first_name: Timmy full_name: Schäfer, Timmy last_name: Schäfer - first_name: Stefan full_name: Spirk, Stefan last_name: Spirk - first_name: Markus full_name: Biesalski, Markus last_name: Biesalski - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann citation: ama: Höfler MV, Lins J, Seelinger D, et al. DNP enhanced solid-state NMR – A powerful tool to address the surface functionalization of cellulose/paper derived materials. Journal of Magnetic Resonance Open. 2024;21:100163. doi:10.1016/j.jmro.2024.100163 apa: Höfler, M. V., Lins, J., Seelinger, D., Pachernegg, L., Schäfer, T., Spirk, S., Biesalski, M., & Gutmann, T. (2024). DNP enhanced solid-state NMR – A powerful tool to address the surface functionalization of cellulose/paper derived materials. Journal of Magnetic Resonance Open, 21, 100163. https://doi.org/10.1016/j.jmro.2024.100163 bibtex: '@article{Höfler_Lins_Seelinger_Pachernegg_Schäfer_Spirk_Biesalski_Gutmann_2024, title={DNP enhanced solid-state NMR – A powerful tool to address the surface functionalization of cellulose/paper derived materials}, volume={21}, DOI={10.1016/j.jmro.2024.100163}, journal={Journal of Magnetic Resonance Open}, author={Höfler, Mark V. and Lins, Jonas and Seelinger, David and Pachernegg, Lukas and Schäfer, Timmy and Spirk, Stefan and Biesalski, Markus and Gutmann, Torsten}, year={2024}, pages={100163} }' chicago: 'Höfler, Mark V., Jonas Lins, David Seelinger, Lukas Pachernegg, Timmy Schäfer, Stefan Spirk, Markus Biesalski, and Torsten Gutmann. “DNP Enhanced Solid-State NMR – A Powerful Tool to Address the Surface Functionalization of Cellulose/Paper Derived Materials.” Journal of Magnetic Resonance Open 21 (2024): 100163. https://doi.org/10.1016/j.jmro.2024.100163.' ieee: 'M. V. Höfler et al., “DNP enhanced solid-state NMR – A powerful tool to address the surface functionalization of cellulose/paper derived materials,” Journal of Magnetic Resonance Open, vol. 21, p. 100163, 2024, doi: 10.1016/j.jmro.2024.100163.' mla: Höfler, Mark V., et al. “DNP Enhanced Solid-State NMR – A Powerful Tool to Address the Surface Functionalization of Cellulose/Paper Derived Materials.” Journal of Magnetic Resonance Open, vol. 21, 2024, p. 100163, doi:10.1016/j.jmro.2024.100163. short: M.V. Höfler, J. Lins, D. Seelinger, L. Pachernegg, T. Schäfer, S. Spirk, M. Biesalski, T. Gutmann, Journal of Magnetic Resonance Open 21 (2024) 100163. date_created: 2026-02-07T15:46:32Z date_updated: 2026-02-17T16:16:40Z doi: 10.1016/j.jmro.2024.100163 extern: '1' intvolume: ' 21' keyword: - solid-state nmr - dynamic nuclear polarization - Hydroxypropyl cellulose - Selective enhancement - Spin labelling language: - iso: eng page: '100163' publication: Journal of Magnetic Resonance Open status: public title: DNP enhanced solid-state NMR – A powerful tool to address the surface functionalization of cellulose/paper derived materials type: journal_article user_id: '100715' volume: 21 year: '2024' ... --- _id: '63974' abstract: - lang: eng text: A versatile strategy for synthesizing tailored peptide based biradicals is presented. By labeling the protected amino acid hydroxyproline with PROXYL via the OH functionality and using this building block in solid phase peptide synthesis (SPPS), the obtained peptides become polarization agents for DNP enhanced solid-state NMR in biotolerant media. To analyze the effect of the radical position on the enhancement factor, three different biradicals are synthesized. The PROXYL spin-label is inserted in a collagen inspired artificial peptide sequence by binding through the OH group of the hydroxyproline moieties at specific position in the chain. This labeling strategy is universally applicable for any hydroxyproline position in a peptide sequence since solid-phase peptide synthesis is used to insert the building block. High performance liquid chromatography (HPLC) and mass spectrometry (MS) analyses show the successful introduction of the spin label in the peptide chain and electron paramagnetic resonance (EPR) spectroscopy confirms its activity. Dynamic nuclear polarization (DNP) enhanced solid-state nuclear magnetic resonance (NMR) experiments performed on frozen aqueous glycerol-d8 solutions containing these peptide radicals show significantly higher enhancement factors of up to 45 in 1H→13C cross polarization magic angle spinning (CP MAS) experiments compared to an analogous mono-radical peptide including this building block (ε ≈ 14). Compared to commercial biradicals such as AMUPol for which enhancement factors {\textgreater} 100 have been obtained in the past and which have been optimized in their structure, the obtained enhancement up to 45 for our biradicals presents a significant progress in radical design. author: - first_name: Kevin full_name: Herr, Kevin last_name: Herr - first_name: Mark V. full_name: Höfler, Mark V. last_name: Höfler - first_name: Henrike full_name: Heise, Henrike last_name: Heise - first_name: Fabien full_name: Aussenac, Fabien last_name: Aussenac - first_name: Felix full_name: Kornemann, Felix last_name: Kornemann - first_name: David full_name: Rosenberger, David last_name: Rosenberger - first_name: Martin full_name: Brodrecht, Martin last_name: Brodrecht - first_name: Marcos full_name: Oliveira, Marcos last_name: Oliveira - first_name: Gerd full_name: Buntkowsky, Gerd last_name: Buntkowsky - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann citation: ama: Herr K, Höfler MV, Heise H, et al. Biradicals based on PROXYL containing building blocks for efficient dynamic nuclear polarization in biotolerant media. Journal of Magnetic Resonance Open. 2024;20:100152. doi:10.1016/j.jmro.2024.100152 apa: Herr, K., Höfler, M. V., Heise, H., Aussenac, F., Kornemann, F., Rosenberger, D., Brodrecht, M., Oliveira, M., Buntkowsky, G., & Gutmann, T. (2024). Biradicals based on PROXYL containing building blocks for efficient dynamic nuclear polarization in biotolerant media. Journal of Magnetic Resonance Open, 20, 100152. https://doi.org/10.1016/j.jmro.2024.100152 bibtex: '@article{Herr_Höfler_Heise_Aussenac_Kornemann_Rosenberger_Brodrecht_Oliveira_Buntkowsky_Gutmann_2024, title={Biradicals based on PROXYL containing building blocks for efficient dynamic nuclear polarization in biotolerant media}, volume={20}, DOI={10.1016/j.jmro.2024.100152}, journal={Journal of Magnetic Resonance Open}, author={Herr, Kevin and Höfler, Mark V. and Heise, Henrike and Aussenac, Fabien and Kornemann, Felix and Rosenberger, David and Brodrecht, Martin and Oliveira, Marcos and Buntkowsky, Gerd and Gutmann, Torsten}, year={2024}, pages={100152} }' chicago: 'Herr, Kevin, Mark V. Höfler, Henrike Heise, Fabien Aussenac, Felix Kornemann, David Rosenberger, Martin Brodrecht, Marcos Oliveira, Gerd Buntkowsky, and Torsten Gutmann. “Biradicals Based on PROXYL Containing Building Blocks for Efficient Dynamic Nuclear Polarization in Biotolerant Media.” Journal of Magnetic Resonance Open 20 (2024): 100152. https://doi.org/10.1016/j.jmro.2024.100152.' ieee: 'K. Herr et al., “Biradicals based on PROXYL containing building blocks for efficient dynamic nuclear polarization in biotolerant media,” Journal of Magnetic Resonance Open, vol. 20, p. 100152, 2024, doi: 10.1016/j.jmro.2024.100152.' mla: Herr, Kevin, et al. “Biradicals Based on PROXYL Containing Building Blocks for Efficient Dynamic Nuclear Polarization in Biotolerant Media.” Journal of Magnetic Resonance Open, vol. 20, 2024, p. 100152, doi:10.1016/j.jmro.2024.100152. short: K. Herr, M.V. Höfler, H. Heise, F. Aussenac, F. Kornemann, D. Rosenberger, M. Brodrecht, M. Oliveira, G. Buntkowsky, T. Gutmann, Journal of Magnetic Resonance Open 20 (2024) 100152. date_created: 2026-02-07T15:42:00Z date_updated: 2026-02-17T16:17:22Z doi: 10.1016/j.jmro.2024.100152 extern: '1' intvolume: ' 20' keyword: - solid-state nmr - dynamic nuclear polarization - peptides - Biradicals - Spin labeling language: - iso: eng page: '100152' publication: Journal of Magnetic Resonance Open status: public title: Biradicals based on PROXYL containing building blocks for efficient dynamic nuclear polarization in biotolerant media type: journal_article user_id: '100715' volume: 20 year: '2024' ... --- _id: '63970' abstract: - lang: eng text: Abstract Recent advances in solid-state nuclear magnetic resonance (NMR) spectroscopy, combined with dynamic nuclear polarization (DNP), quantum chemical DFT calculations, and gas-phase NMR spectroscopy investigating the structure and reactivity of heterogeneous catalysts are reviewed. The investigated catalysts range from classical mononuclear catalysts, like immobilized derivates of Wilkinson’s catalysts over binuclear catalysts such as the dirhodium paddlewheel catalyst to catalytic nanoparticles, employing various support materials, such as mesoporous silica gels, coordination polymers, and biomaterials such as cellulose. author: - first_name: Nadia full_name: Haro Mares, Nadia last_name: Haro Mares - first_name: Millena full_name: Logrado, Millena last_name: Logrado - first_name: Jan full_name: Kergassner, Jan last_name: Kergassner - first_name: Bingyu full_name: Zhang, Bingyu last_name: Zhang - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: Gerd full_name: Buntkowsky, Gerd last_name: Buntkowsky citation: ama: Haro Mares N, Logrado M, Kergassner J, Zhang B, Gutmann T, Buntkowsky G. Solid-State NMR of Heterogeneous Catalysts. ChemCatChem. Published online 2024:e202401159. doi:10.1002/cctc.202401159 apa: Haro Mares, N., Logrado, M., Kergassner, J., Zhang, B., Gutmann, T., & Buntkowsky, G. (2024). Solid-State NMR of Heterogeneous Catalysts. ChemCatChem, e202401159. https://doi.org/10.1002/cctc.202401159 bibtex: '@article{Haro Mares_Logrado_Kergassner_Zhang_Gutmann_Buntkowsky_2024, title={Solid-State NMR of Heterogeneous Catalysts}, DOI={10.1002/cctc.202401159}, journal={ChemCatChem}, publisher={John Wiley & Sons, Ltd}, author={Haro Mares, Nadia and Logrado, Millena and Kergassner, Jan and Zhang, Bingyu and Gutmann, Torsten and Buntkowsky, Gerd}, year={2024}, pages={e202401159} }' chicago: Haro Mares, Nadia, Millena Logrado, Jan Kergassner, Bingyu Zhang, Torsten Gutmann, and Gerd Buntkowsky. “Solid-State NMR of Heterogeneous Catalysts.” ChemCatChem, 2024, e202401159. https://doi.org/10.1002/cctc.202401159. ieee: 'N. Haro Mares, M. Logrado, J. Kergassner, B. Zhang, T. Gutmann, and G. Buntkowsky, “Solid-State NMR of Heterogeneous Catalysts,” ChemCatChem, p. e202401159, 2024, doi: 10.1002/cctc.202401159.' mla: Haro Mares, Nadia, et al. “Solid-State NMR of Heterogeneous Catalysts.” ChemCatChem, John Wiley & Sons, Ltd, 2024, p. e202401159, doi:10.1002/cctc.202401159. short: N. Haro Mares, M. Logrado, J. Kergassner, B. Zhang, T. Gutmann, G. Buntkowsky, ChemCatChem (2024) e202401159. date_created: 2026-02-07T15:40:38Z date_updated: 2026-02-17T16:17:30Z doi: 10.1002/cctc.202401159 extern: '1' keyword: - solid-state nmr - heterogeneous catalysis - dynamic nuclear polarization - Nanocatalysis - Surface-reactions language: - iso: eng page: e202401159 publication: ChemCatChem publication_identifier: issn: - 1867-3880 publisher: John Wiley & Sons, Ltd status: public title: Solid-State NMR of Heterogeneous Catalysts type: journal_article user_id: '100715' year: '2024' ... --- _id: '64045' abstract: - lang: eng text: Abstract In this work, we report on an improved cell assembly of cylindrical electrochemical cells for 23Na in-situ solid-state NMR (ssNMR) investigations. The cell set-up is suitable for using powder electrode materials. Reproducibility of our cell assembly is analyzed by preparing two cells containing hard carbon (HC) powder as working electrode and sodium metal as reference electrode. Electrochemical storage properties of HC powder electrode derived from carbonization of sustainable cellulose are studied by ssNMR. 23Na in-situ ssNMR monitors the sodiation/desodiation of a Na{\textbar}NaPF6{\textbar}HC cell (cell 1) over a period of 22?days, showing high cell stability. After the galvanostatic process, the HC powder material is investigated by high resolution 23Na ex-situ MAS NMR. The formation of ionic sodium species in different chemical environments is obtained. Subsequently, a second Na{\textbar}NaPF6{\textbar}HC cell (cell 2) is sodiated for 11?days achieving a capacity of 220?mAh/g. 23Na ex-situ MAS NMR measurements of the HC powder material extracted from this cell clearly indicate the presence of quasi-metallic sodium species next to ionic sodium species. This observation of quasi-metallic sodium species is discussed in terms of the achieved capacity of the cell as well as of side reactions of sodium in this electrode material. author: - first_name: Edina full_name: Šić, Edina last_name: Šić - first_name: Konstantin full_name: Schutjajew, Konstantin last_name: Schutjajew - first_name: Ulrich full_name: Haagen, Ulrich last_name: Haagen - first_name: Hergen full_name: Breitzke, Hergen last_name: Breitzke - first_name: Martin full_name: Oschatz, Martin last_name: Oschatz - first_name: Gerd full_name: Buntkowsky, Gerd last_name: Buntkowsky - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann citation: ama: 'Šić E, Schutjajew K, Haagen U, et al. Electrochemical Sodium Storage in Hard Carbon Powder Electrodes Implemented in an Improved Cell Assembly: Insights from In-Situ and Ex-Situ Solid-State NMR. Chemsuschem. 2023;17:e202301300. doi:10.1002/cssc.202301300' apa: 'Šić, E., Schutjajew, K., Haagen, U., Breitzke, H., Oschatz, M., Buntkowsky, G., & Gutmann, T. (2023). Electrochemical Sodium Storage in Hard Carbon Powder Electrodes Implemented in an Improved Cell Assembly: Insights from In-Situ and Ex-Situ Solid-State NMR. Chemsuschem, 17, e202301300. https://doi.org/10.1002/cssc.202301300' bibtex: '@article{Šić_Schutjajew_Haagen_Breitzke_Oschatz_Buntkowsky_Gutmann_2023, title={Electrochemical Sodium Storage in Hard Carbon Powder Electrodes Implemented in an Improved Cell Assembly: Insights from In-Situ and Ex-Situ Solid-State NMR}, volume={17}, DOI={10.1002/cssc.202301300}, journal={Chemsuschem}, publisher={John Wiley & Sons, Ltd}, author={Šić, Edina and Schutjajew, Konstantin and Haagen, Ulrich and Breitzke, Hergen and Oschatz, Martin and Buntkowsky, Gerd and Gutmann, Torsten}, year={2023}, pages={e202301300} }' chicago: 'Šić, Edina, Konstantin Schutjajew, Ulrich Haagen, Hergen Breitzke, Martin Oschatz, Gerd Buntkowsky, and Torsten Gutmann. “Electrochemical Sodium Storage in Hard Carbon Powder Electrodes Implemented in an Improved Cell Assembly: Insights from In-Situ and Ex-Situ Solid-State NMR.” Chemsuschem 17 (2023): e202301300. https://doi.org/10.1002/cssc.202301300.' ieee: 'E. Šić et al., “Electrochemical Sodium Storage in Hard Carbon Powder Electrodes Implemented in an Improved Cell Assembly: Insights from In-Situ and Ex-Situ Solid-State NMR,” Chemsuschem, vol. 17, p. e202301300, 2023, doi: 10.1002/cssc.202301300.' mla: 'Šić, Edina, et al. “Electrochemical Sodium Storage in Hard Carbon Powder Electrodes Implemented in an Improved Cell Assembly: Insights from In-Situ and Ex-Situ Solid-State NMR.” Chemsuschem, vol. 17, John Wiley & Sons, Ltd, 2023, p. e202301300, doi:10.1002/cssc.202301300.' short: E. Šić, K. Schutjajew, U. Haagen, H. Breitzke, M. Oschatz, G. Buntkowsky, T. Gutmann, Chemsuschem 17 (2023) e202301300. date_created: 2026-02-07T16:12:13Z date_updated: 2026-02-17T16:13:10Z doi: 10.1002/cssc.202301300 extern: '1' intvolume: ' 17' keyword: - solid-state nmr - hard carbon - electrochemical cells - in-situ characterization - sodium language: - iso: eng page: e202301300 publication: Chemsuschem publication_identifier: issn: - 1864-5631 publisher: John Wiley & Sons, Ltd status: public title: 'Electrochemical Sodium Storage in Hard Carbon Powder Electrodes Implemented in an Improved Cell Assembly: Insights from In-Situ and Ex-Situ Solid-State NMR' type: journal_article user_id: '100715' volume: 17 year: '2023' ... --- _id: '64044' abstract: - lang: eng text: Abstract Polymer-derived silicon oxycarbide ceramics (SiCO) have been considered as potential anode materials for lithium- and sodium-ion batteries. To understand their electrochemical storage behavior, detailed insights into structural sites present in SiCO are required. In this work, the study of local structures in SiCO ceramics containing different amounts of carbon is presented. 13C and 29Si solid-state MAS?NMR spectroscopy combined with DFT calculations, atomistic modeling, and EPR investigations, suggest significant changes in the local structures of SiCO ceramics even by small changes in the material composition. The provided findings on SiCO structures will contribute to the research field of polymer-derived ceramics, especially to understand electrochemical storage processes of alkali metal/ions such as Na/Na+ inside such networks in the future. author: - first_name: Edina full_name: Šić, Edina last_name: Šić - first_name: Jochen full_name: Rohrer, Jochen last_name: Rohrer - first_name: Emmanuel full_name: Ricohermoso, Emmanuel last_name: Ricohermoso - first_name: Karsten full_name: Albe, Karsten last_name: Albe - first_name: Emmanuel full_name: Ionescu, Emmanuel last_name: Ionescu - first_name: Ralf full_name: Riedel, Ralf last_name: Riedel - first_name: Hergen full_name: Breitzke, Hergen last_name: Breitzke - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: Gerd full_name: Buntkowsky, Gerd last_name: Buntkowsky citation: ama: 'Šić E, Rohrer J, Ricohermoso E, et al. SiCO Ceramics as Storage Materials for Alkali Metals/Ions: Insights on Structure Moieties from Solid-State NMR and DFT Calculations. Chemsuschem. 2023;16:e202202241. doi:10.1002/cssc.202202241' apa: 'Šić, E., Rohrer, J., Ricohermoso, E., Albe, K., Ionescu, E., Riedel, R., Breitzke, H., Gutmann, T., & Buntkowsky, G. (2023). SiCO Ceramics as Storage Materials for Alkali Metals/Ions: Insights on Structure Moieties from Solid-State NMR and DFT Calculations. Chemsuschem, 16, e202202241. https://doi.org/10.1002/cssc.202202241' bibtex: '@article{Šić_Rohrer_Ricohermoso_Albe_Ionescu_Riedel_Breitzke_Gutmann_Buntkowsky_2023, title={SiCO Ceramics as Storage Materials for Alkali Metals/Ions: Insights on Structure Moieties from Solid-State NMR and DFT Calculations}, volume={16}, DOI={10.1002/cssc.202202241}, journal={Chemsuschem}, publisher={John Wiley & Sons, Ltd}, author={Šić, Edina and Rohrer, Jochen and Ricohermoso, Emmanuel and Albe, Karsten and Ionescu, Emmanuel and Riedel, Ralf and Breitzke, Hergen and Gutmann, Torsten and Buntkowsky, Gerd}, year={2023}, pages={e202202241} }' chicago: 'Šić, Edina, Jochen Rohrer, Emmanuel Ricohermoso, Karsten Albe, Emmanuel Ionescu, Ralf Riedel, Hergen Breitzke, Torsten Gutmann, and Gerd Buntkowsky. “SiCO Ceramics as Storage Materials for Alkali Metals/Ions: Insights on Structure Moieties from Solid-State NMR and DFT Calculations.” Chemsuschem 16 (2023): e202202241. https://doi.org/10.1002/cssc.202202241.' ieee: 'E. Šić et al., “SiCO Ceramics as Storage Materials for Alkali Metals/Ions: Insights on Structure Moieties from Solid-State NMR and DFT Calculations,” Chemsuschem, vol. 16, p. e202202241, 2023, doi: 10.1002/cssc.202202241.' mla: 'Šić, Edina, et al. “SiCO Ceramics as Storage Materials for Alkali Metals/Ions: Insights on Structure Moieties from Solid-State NMR and DFT Calculations.” Chemsuschem, vol. 16, John Wiley & Sons, Ltd, 2023, p. e202202241, doi:10.1002/cssc.202202241.' short: E. Šić, J. Rohrer, E. Ricohermoso, K. Albe, E. Ionescu, R. Riedel, H. Breitzke, T. Gutmann, G. Buntkowsky, Chemsuschem 16 (2023) e202202241. date_created: 2026-02-07T16:11:46Z date_updated: 2026-02-17T16:13:11Z doi: 10.1002/cssc.202202241 extern: '1' intvolume: ' 16' keyword: - NMR spectroscopy - Ceramics - defects - density functional calculations - EPR spectroscopy language: - iso: eng page: e202202241 publication: Chemsuschem publication_identifier: issn: - 1864-5631 publisher: John Wiley & Sons, Ltd status: public title: 'SiCO Ceramics as Storage Materials for Alkali Metals/Ions: Insights on Structure Moieties from Solid-State NMR and DFT Calculations' type: journal_article user_id: '100715' volume: 16 year: '2023' ... --- _id: '63948' abstract: - lang: eng text: In this work, the behavior of four different commercially available polarizing agents is investigated employing the non-ionic model surfactant 1-octanol as analyte. A relative method for the comparison of the proportion of the direct and indirect polarization transfer pathways is established, allowing a direct comparison of the polarization efficacy for different radicals and different parts of the 1-octanol molecule despite differences in radical concentration or sample amount. With this approach, it could be demonstrated that the hydrophilicity is a key factor in the way polarization is transferred from the polarizing agent to the analyte. These findings are confirmed by the determination of buildup times Tb, illustrating that the choice of polarizing agent plays an essential role in ensuring an optimal polarization transfer and therefore the maximum amount of enhancement possible for DNP enhanced NMR measurements. author: - first_name: Sonja C. full_name: Döller, Sonja C. last_name: Döller - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: Markus full_name: Hoffmann, Markus last_name: Hoffmann - first_name: Gerd full_name: Buntkowsky, Gerd last_name: Buntkowsky citation: ama: Döller SC, Gutmann T, Hoffmann M, Buntkowsky G. A case study on the influence of hydrophilicity on the signal enhancement by dynamic nuclear polarization. Solid State Nuclear Magnetic Resonance. 2022;122:101829. apa: Döller, S. C., Gutmann, T., Hoffmann, M., & Buntkowsky, G. (2022). A case study on the influence of hydrophilicity on the signal enhancement by dynamic nuclear polarization. Solid State Nuclear Magnetic Resonance, 122, 101829. bibtex: '@article{Döller_Gutmann_Hoffmann_Buntkowsky_2022, title={A case study on the influence of hydrophilicity on the signal enhancement by dynamic nuclear polarization}, volume={122}, journal={Solid State Nuclear Magnetic Resonance}, author={Döller, Sonja C. and Gutmann, Torsten and Hoffmann, Markus and Buntkowsky, Gerd}, year={2022}, pages={101829} }' chicago: 'Döller, Sonja C., Torsten Gutmann, Markus Hoffmann, and Gerd Buntkowsky. “A Case Study on the Influence of Hydrophilicity on the Signal Enhancement by Dynamic Nuclear Polarization.” Solid State Nuclear Magnetic Resonance 122 (2022): 101829.' ieee: S. C. Döller, T. Gutmann, M. Hoffmann, and G. Buntkowsky, “A case study on the influence of hydrophilicity on the signal enhancement by dynamic nuclear polarization,” Solid State Nuclear Magnetic Resonance, vol. 122, p. 101829, 2022. mla: Döller, Sonja C., et al. “A Case Study on the Influence of Hydrophilicity on the Signal Enhancement by Dynamic Nuclear Polarization.” Solid State Nuclear Magnetic Resonance, vol. 122, 2022, p. 101829. short: S.C. Döller, T. Gutmann, M. Hoffmann, G. Buntkowsky, Solid State Nuclear Magnetic Resonance 122 (2022) 101829. date_created: 2026-02-07T09:13:08Z date_updated: 2026-02-17T16:18:26Z extern: '1' intvolume: ' 122' keyword: - DNP NMR - Dynamics - Low temperature NMR - Octanol - Solid state NMR - Surfactants language: - iso: eng page: '101829' publication: Solid State Nuclear Magnetic Resonance status: public title: A case study on the influence of hydrophilicity on the signal enhancement by dynamic nuclear polarization type: journal_article user_id: '100715' volume: 122 year: '2022' ... --- _id: '63943' abstract: - lang: eng text: A lithium halide exchange reaction at low-temperature, via the treatment of 2,6-di(isopropyl)phenyllithium on 1,1′-bis-(dichlorophosphino)ferrocene, resulted in the first isolated example of an aryl-substituted diphospha [2]ferrocenophane (diphospha [2]FCP) 2. Although compound 2 did not show any recognizable thermal reaction at higher temperature (up to 350 °C), its tert-butyl-substituted counterpart 1 underwent a clean selective heat-mediated P–C cleavage reaction, followed by an inter-molecular rearrangement, to produce a P–P fused bis [3]ferrocenophane 3 with all-trans oriented P-chain, which upon further heating gave a polyferrocenylphosphane tBu-[Fc’P2]n-tBu (4). Since polymer 4 is insoluble in common organic solvents, it has been characterized with solid-state techniques, including solid-state NMR. Density functional theory (DFT) has further been employed to identify possible pathways for P–C bond cleavage on 1 and 2, as well as to evaluate accessible pathways for further polymerization toward 4. author: - first_name: Subhayan full_name: Dey, Subhayan last_name: Dey - first_name: Denis full_name: Kargin, Denis last_name: Kargin - first_name: Mark V. full_name: Höfler, Mark V. last_name: Höfler - first_name: Balazs full_name: Szathmari, Balazs last_name: Szathmari - first_name: Clemens full_name: Bruhn, Clemens last_name: Bruhn - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: Zsolt full_name: Kelemen, Zsolt last_name: Kelemen - first_name: Rudolf full_name: Pietschnig, Rudolf last_name: Pietschnig citation: ama: Dey S, Kargin D, Höfler MV, et al. Oligo- and polymerization of phospha [2]ferrocenophanes to one dimensional phosphorus chains with ferrocenylene handles. Polymer. 2022;242:124589. apa: Dey, S., Kargin, D., Höfler, M. V., Szathmari, B., Bruhn, C., Gutmann, T., Kelemen, Z., & Pietschnig, R. (2022). Oligo- and polymerization of phospha [2]ferrocenophanes to one dimensional phosphorus chains with ferrocenylene handles. Polymer, 242, 124589. bibtex: '@article{Dey_Kargin_Höfler_Szathmari_Bruhn_Gutmann_Kelemen_Pietschnig_2022, title={Oligo- and polymerization of phospha [2]ferrocenophanes to one dimensional phosphorus chains with ferrocenylene handles}, volume={242}, journal={Polymer}, author={Dey, Subhayan and Kargin, Denis and Höfler, Mark V. and Szathmari, Balazs and Bruhn, Clemens and Gutmann, Torsten and Kelemen, Zsolt and Pietschnig, Rudolf}, year={2022}, pages={124589} }' chicago: 'Dey, Subhayan, Denis Kargin, Mark V. Höfler, Balazs Szathmari, Clemens Bruhn, Torsten Gutmann, Zsolt Kelemen, and Rudolf Pietschnig. “Oligo- and Polymerization of Phospha [2]Ferrocenophanes to One Dimensional Phosphorus Chains with Ferrocenylene Handles.” Polymer 242 (2022): 124589.' ieee: S. Dey et al., “Oligo- and polymerization of phospha [2]ferrocenophanes to one dimensional phosphorus chains with ferrocenylene handles,” Polymer, vol. 242, p. 124589, 2022. mla: Dey, Subhayan, et al. “Oligo- and Polymerization of Phospha [2]Ferrocenophanes to One Dimensional Phosphorus Chains with Ferrocenylene Handles.” Polymer, vol. 242, 2022, p. 124589. short: S. Dey, D. Kargin, M.V. Höfler, B. Szathmari, C. Bruhn, T. Gutmann, Z. Kelemen, R. Pietschnig, Polymer 242 (2022) 124589. date_created: 2026-02-07T09:10:38Z date_updated: 2026-02-17T16:18:36Z extern: '1' intvolume: ' 242' keyword: - solid-state nmr - Ansa-ferrocene - DFT calculations - Oligophosphine - Polyphosphane - Ring-opening polymerization language: - iso: eng page: '124589' publication: Polymer status: public title: Oligo- and polymerization of phospha [2]ferrocenophanes to one dimensional phosphorus chains with ferrocenylene handles type: journal_article user_id: '100715' volume: 242 year: '2022' ... --- _id: '35398' abstract: - lang: eng text: The Haller relationship was applied to estimate the nematic order parameter S from 1H NMR spectra of fully protonated liquid crystals aligned in the magnetic field. The NMR line shapes were approximated as doublets of very broad peaks. Both the temperature-dependent doublet Splitting and the full width at half maximum of the whole spectra were used for Haller extrapolation. The order parameters obtained with the proposed approach for 4-cyano-4'-pentylbiphenyl (5CB) and the nematic mixture E7 were found to be in good agreement with previously reports. article_type: original author: - first_name: Ming-xue full_name: Tang, Ming-xue last_name: Tang - first_name: Claudia full_name: Schmidt, Claudia id: '466' last_name: Schmidt orcid: 0000-0003-3179-9997 citation: ama: Tang M, Schmidt C. Estimation of Nematic Order Parameters via Haller Analysis of 1H NMR Spectra of Liquid Crystals . Chinese Journal of Magnetic Resonance. 2019;36:138-147. doi:10.11938/cjmr20182685 apa: Tang, M., & Schmidt, C. (2019). Estimation of Nematic Order Parameters via Haller Analysis of 1H NMR Spectra of Liquid Crystals . Chinese Journal of Magnetic Resonance, 36, 138–147. https://doi.org/10.11938/cjmr20182685 bibtex: '@article{Tang_Schmidt_2019, title={Estimation of Nematic Order Parameters via Haller Analysis of 1H NMR Spectra of Liquid Crystals }, volume={36}, DOI={10.11938/cjmr20182685 }, journal={Chinese Journal of Magnetic Resonance}, author={Tang, Ming-xue and Schmidt, Claudia}, year={2019}, pages={138–147} }' chicago: 'Tang, Ming-xue, and Claudia Schmidt. “Estimation of Nematic Order Parameters via Haller Analysis of 1H NMR Spectra of Liquid Crystals .” Chinese Journal of Magnetic Resonance 36 (2019): 138–47. https://doi.org/10.11938/cjmr20182685 .' ieee: 'M. Tang and C. Schmidt, “Estimation of Nematic Order Parameters via Haller Analysis of 1H NMR Spectra of Liquid Crystals ,” Chinese Journal of Magnetic Resonance, vol. 36, pp. 138–147, 2019, doi: 10.11938/cjmr20182685 .' mla: Tang, Ming-xue, and Claudia Schmidt. “Estimation of Nematic Order Parameters via Haller Analysis of 1H NMR Spectra of Liquid Crystals .” Chinese Journal of Magnetic Resonance, vol. 36, 2019, pp. 138–47, doi:10.11938/cjmr20182685 . short: M. Tang, C. Schmidt, Chinese Journal of Magnetic Resonance 36 (2019) 138–147. date_created: 2023-01-06T17:29:26Z date_updated: 2023-01-07T10:31:24Z department: - _id: '2' - _id: '315' doi: '10.11938/cjmr20182685 ' intvolume: ' 36' keyword: - nematic liquid crystal - order parameter - Haller analysis - 1H NMR language: - iso: eng page: 138-147 publication: Chinese Journal of Magnetic Resonance quality_controlled: '1' related_material: link: - relation: research_paper url: http://121.43.60.238/bpxzz/EN/10.11938/cjmr20182685 status: public title: 'Estimation of Nematic Order Parameters via Haller Analysis of 1H NMR Spectra of Liquid Crystals ' type: journal_article user_id: '466' volume: 36 year: '2019' ... --- _id: '64018' abstract: - lang: eng text: CO oxidation is an extensively studied reaction in heterogeneous catalysis due to its seeming simplicity and its great importance for emission control. However, the role of particle size and more specifically structure sensitivity in this reaction is still controversial. In the present study, colloidal “surfactant-free” Pt nanoparticles (NPs) in a size regime of 1–4 nm with narrow size distribution and control over particle size were synthesized and subsequently supported on Al2O3 to prepare model catalysts. CO oxidation was performed using Pt NPs catalysts with particles sizes of 1, 2, 3, and 4 nm at different reaction temperatures. It is shown that the reaction exhibits a particle size effect that depends strongly on the reaction conditions. At 170 °C, the reaction seems to proceed within the same kinetic regime for all particle sizes, but the surface normalized activity depends strongly on the particle size, with maximum activity for nanoparticles 2 nm in diameter. A temperature increase to 200 °C leads to a change of the kinetic regime that depends on the particle size. For Pt NPs 1 nm in diameter a reaction order of 1 for O2 was observed, indicating that O2 adsorbs molecularly and dissociates in a following step, which represents the generally accepted mechanism on Pt surfaces. The reaction order of −1 for CO demonstrates that the surface is saturated with CO under reaction conditions. With increasing particle size, the reaction orders of O2 and CO change. For particles 2 nm in size, an increase in temperature also results in reaction orders of 1 for O2 and −1 for CO; NPs of 3 and 4 nm, even at higher temperatures, show no clear kinetic behavior that can be explained by a single reaction mechanism. Instead, the Boudouard reaction between two adjacent adsorbed CO molecules was identified as an important additional reaction pathway that occurs preferentially on large particles and causes more complex kinetics. author: - first_name: Sarah full_name: Neumann, Sarah last_name: Neumann - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: Gerd full_name: Buntkowsky, Gerd last_name: Buntkowsky - first_name: Stephen full_name: Paul, Stephen last_name: Paul - first_name: Greg full_name: Thiele, Greg last_name: Thiele - first_name: Heiko full_name: Sievers, Heiko last_name: Sievers - first_name: Marcus full_name: Bäumer, Marcus last_name: Bäumer - first_name: Sebastian full_name: Kunz, Sebastian last_name: Kunz citation: ama: Neumann S, Gutmann T, Buntkowsky G, et al. Insights into the reaction mechanism and particle size effects of CO oxidation over supported Pt nanoparticle catalysts. Journal of Catalysis. 2019;377:662–672. doi:10.1016/j.jcat.2019.07.049 apa: Neumann, S., Gutmann, T., Buntkowsky, G., Paul, S., Thiele, G., Sievers, H., Bäumer, M., & Kunz, S. (2019). Insights into the reaction mechanism and particle size effects of CO oxidation over supported Pt nanoparticle catalysts. Journal of Catalysis, 377, 662–672. https://doi.org/10.1016/j.jcat.2019.07.049 bibtex: '@article{Neumann_Gutmann_Buntkowsky_Paul_Thiele_Sievers_Bäumer_Kunz_2019, title={Insights into the reaction mechanism and particle size effects of CO oxidation over supported Pt nanoparticle catalysts}, volume={377}, DOI={10.1016/j.jcat.2019.07.049}, journal={Journal of Catalysis}, author={Neumann, Sarah and Gutmann, Torsten and Buntkowsky, Gerd and Paul, Stephen and Thiele, Greg and Sievers, Heiko and Bäumer, Marcus and Kunz, Sebastian}, year={2019}, pages={662–672} }' chicago: 'Neumann, Sarah, Torsten Gutmann, Gerd Buntkowsky, Stephen Paul, Greg Thiele, Heiko Sievers, Marcus Bäumer, and Sebastian Kunz. “Insights into the Reaction Mechanism and Particle Size Effects of CO Oxidation over Supported Pt Nanoparticle Catalysts.” Journal of Catalysis 377 (2019): 662–672. https://doi.org/10.1016/j.jcat.2019.07.049.' ieee: 'S. Neumann et al., “Insights into the reaction mechanism and particle size effects of CO oxidation over supported Pt nanoparticle catalysts,” Journal of Catalysis, vol. 377, pp. 662–672, 2019, doi: 10.1016/j.jcat.2019.07.049.' mla: Neumann, Sarah, et al. “Insights into the Reaction Mechanism and Particle Size Effects of CO Oxidation over Supported Pt Nanoparticle Catalysts.” Journal of Catalysis, vol. 377, 2019, pp. 662–672, doi:10.1016/j.jcat.2019.07.049. short: S. Neumann, T. Gutmann, G. Buntkowsky, S. Paul, G. Thiele, H. Sievers, M. Bäumer, S. Kunz, Journal of Catalysis 377 (2019) 662–672. date_created: 2026-02-07T16:02:06Z date_updated: 2026-02-17T16:14:45Z doi: 10.1016/j.jcat.2019.07.049 extern: '1' intvolume: ' 377' keyword: - Solid state NMR - “Surfactant-free” platinum nanoparticles - CO oxidation - Particle size effect - Structure sensitivity language: - iso: eng page: 662–672 publication: Journal of Catalysis status: public title: Insights into the reaction mechanism and particle size effects of CO oxidation over supported Pt nanoparticle catalysts type: journal_article user_id: '100715' volume: 377 year: '2019' ... --- _id: '63960' abstract: - lang: eng text: Recent advances in solid-state nuclear magnetic resonance (NMR) spectroscopy and dynamic nuclear polarization (DNP) of nanostructured materials are reviewed. A first group of materials is based on crystalline nanocellulose (CNC) or microcrystalline cellulose (MCC), which are used as carrier materials for dye molecules, catalysts or in combination with heterocyclic molecules as ion conducting membranes. These materials have widespread applications in sensorics, optics, catalysis or fuel cell research. A second group are metal oxides such as V-Mo-W oxides, which are of enormous importance in the manufacturing process of basic chemicals. The third group are catalytically active nanocrystalline metal nanoparticles, coated with protectants or embedded in polymers. The last group includes of lead-free perovskite materials, which are employed as environmentally benign substitution materials for conventional lead-based electronics materials. These materials are discussed in terms of their application and physico-chemical characterization by solid-state NMR techniques, combined with gas-phase NMR and quantum-chemical modelling on the density functional theory (DFT) level. The application of multinuclear 1H, 2H, 13C, 15N and 23Na solid state NMR techniques under static or MAS conditions for the characterization of these materials, their surfaces and processes on their surfaces is discussed. Moreover, the analytic power of the combination of these techniques with DNP for the identification of low-concentrated carbon and nitrogen containing surface species in natural abundance is reviewed. Finally, approaches for sensitivity enhancement by DNP of quadrupolar nuclei such as 17O and 51V are presented that enable the identification of catalytic sites in metal oxide catalysts. author: - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: Pedro B. full_name: Groszewicz, Pedro B. last_name: Groszewicz - first_name: Gerd full_name: Buntkowsky, Gerd last_name: Buntkowsky citation: ama: Gutmann T, Groszewicz PB, Buntkowsky G. Solid-state NMR of nanocrystals. Annual Reports on NMR Spectroscopy. 2019;97:1–82. doi:10.1016/bs.arnmr.2018.12.001 apa: Gutmann, T., Groszewicz, P. B., & Buntkowsky, G. (2019). Solid-state NMR of nanocrystals. Annual Reports on NMR Spectroscopy, 97, 1–82. https://doi.org/10.1016/bs.arnmr.2018.12.001 bibtex: '@article{Gutmann_Groszewicz_Buntkowsky_2019, title={Solid-state NMR of nanocrystals}, volume={97}, DOI={10.1016/bs.arnmr.2018.12.001}, journal={Annual Reports on NMR Spectroscopy}, author={Gutmann, Torsten and Groszewicz, Pedro B. and Buntkowsky, Gerd}, year={2019}, pages={1–82} }' chicago: 'Gutmann, Torsten, Pedro B. Groszewicz, and Gerd Buntkowsky. “Solid-State NMR of Nanocrystals.” Annual Reports on NMR Spectroscopy 97 (2019): 1–82. https://doi.org/10.1016/bs.arnmr.2018.12.001.' ieee: 'T. Gutmann, P. B. Groszewicz, and G. Buntkowsky, “Solid-state NMR of nanocrystals,” Annual Reports on NMR Spectroscopy, vol. 97, pp. 1–82, 2019, doi: 10.1016/bs.arnmr.2018.12.001.' mla: Gutmann, Torsten, et al. “Solid-State NMR of Nanocrystals.” Annual Reports on NMR Spectroscopy, vol. 97, 2019, pp. 1–82, doi:10.1016/bs.arnmr.2018.12.001. short: T. Gutmann, P.B. Groszewicz, G. Buntkowsky, Annual Reports on NMR Spectroscopy 97 (2019) 1–82. date_created: 2026-02-07T15:37:03Z date_updated: 2026-02-17T16:17:56Z doi: 10.1016/bs.arnmr.2018.12.001 extern: '1' intvolume: ' 97' keyword: - solid-state nmr - heterogeneous catalysis - dynamic nuclear polarization - Ferroelectrics - Nanocatalysis - Surface reactions language: - iso: eng page: 1–82 publication: Annual Reports on NMR Spectroscopy status: public title: Solid-state NMR of nanocrystals type: journal_article user_id: '100715' volume: 97 year: '2019' ... --- _id: '64010' abstract: - lang: eng text: Seven novel dirhodium coordination polymers (Rh-2-Ln) (n = 1-7) are prepared by employing bitopic ligands to connect dirhodium nodes. The formation of the framework is confirmed by attenuated total reflectance Fourier transform infrared (ATR-FTIR) and H-1 C-13 cross polarization magic angle spinning nuclear magnetic resonance (CP MAS NMR) spectroscopy. Defect sites resulting from incomplete ligand substitution are revealed by F-19 MAS NMR. The random stacking behavior of the frameworks in the obtained solid is analyzed by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The Rh-2/O interaction in neighboring layers is investigated by diffuse reflectance ultra-violet visible light (DR-UV-vis) spectroscopy and X-ray photoelectron spectroscopy (XPS). This interaction is relevant to understand the catalytic behavior of various Rh-2-Ln catalysts in the cyclopropanation of styrene with ethyl diazoacetate (EDA). In this context, the structure-reactivity relationship is discussed by taking into consideration both interlayer Rh-2/O interactions and steric effects of side chains. author: - first_name: J. Q. full_name: Liu, J. Q. last_name: Liu - first_name: Y. P. full_name: Xu, Y. P. last_name: Xu - first_name: P. B. full_name: Groszewicz, P. B. last_name: Groszewicz - first_name: M. full_name: Brodrecht, M. last_name: Brodrecht - first_name: C. full_name: Fasel, C. last_name: Fasel - first_name: K. full_name: Hofmann, K. last_name: Hofmann - first_name: X. J. full_name: Tan, X. J. last_name: Tan - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: G. full_name: Buntkowsky, G. last_name: Buntkowsky citation: ama: 'Liu JQ, Xu YP, Groszewicz PB, et al. Novel dirhodium coordination polymers: the impact of side chains on cyclopropanation. Catalysis Science & Technology. 2018;8(20):5190–5200. doi:10.1039/c8cy01493k' apa: 'Liu, J. Q., Xu, Y. P., Groszewicz, P. B., Brodrecht, M., Fasel, C., Hofmann, K., Tan, X. J., Gutmann, T., & Buntkowsky, G. (2018). Novel dirhodium coordination polymers: the impact of side chains on cyclopropanation. Catalysis Science & Technology, 8(20), 5190–5200. https://doi.org/10.1039/c8cy01493k' bibtex: '@article{Liu_Xu_Groszewicz_Brodrecht_Fasel_Hofmann_Tan_Gutmann_Buntkowsky_2018, title={Novel dirhodium coordination polymers: the impact of side chains on cyclopropanation}, volume={8}, DOI={10.1039/c8cy01493k}, number={20}, journal={Catalysis Science & Technology}, author={Liu, J. Q. and Xu, Y. P. and Groszewicz, P. B. and Brodrecht, M. and Fasel, C. and Hofmann, K. and Tan, X. J. and Gutmann, Torsten and Buntkowsky, G.}, year={2018}, pages={5190–5200} }' chicago: 'Liu, J. Q., Y. P. Xu, P. B. Groszewicz, M. Brodrecht, C. Fasel, K. Hofmann, X. J. Tan, Torsten Gutmann, and G. Buntkowsky. “Novel Dirhodium Coordination Polymers: The Impact of Side Chains on Cyclopropanation.” Catalysis Science & Technology 8, no. 20 (2018): 5190–5200. https://doi.org/10.1039/c8cy01493k.' ieee: 'J. Q. Liu et al., “Novel dirhodium coordination polymers: the impact of side chains on cyclopropanation,” Catalysis Science & Technology, vol. 8, no. 20, pp. 5190–5200, 2018, doi: 10.1039/c8cy01493k.' mla: 'Liu, J. Q., et al. “Novel Dirhodium Coordination Polymers: The Impact of Side Chains on Cyclopropanation.” Catalysis Science & Technology, vol. 8, no. 20, 2018, pp. 5190–5200, doi:10.1039/c8cy01493k.' short: J.Q. Liu, Y.P. Xu, P.B. Groszewicz, M. Brodrecht, C. Fasel, K. Hofmann, X.J. Tan, T. Gutmann, G. Buntkowsky, Catalysis Science & Technology 8 (2018) 5190–5200. date_created: 2026-02-07T15:57:34Z date_updated: 2026-02-17T16:15:22Z doi: 10.1039/c8cy01493k extern: '1' intvolume: ' 8' issue: '20' keyword: - Chemistry - asymmetric cyclopropanation - c-h insertion - carbene transformations - carboxylates - catalysts - functionalization - immobilization - metal-organic frameworks - nmr - solid support language: - iso: eng page: 5190–5200 publication: Catalysis Science & Technology publication_identifier: issn: - 2044-4753 status: public title: 'Novel dirhodium coordination polymers: the impact of side chains on cyclopropanation' type: journal_article user_id: '100715' volume: 8 year: '2018' ... --- _id: '64053' abstract: - lang: eng text: The utilization and preparation of functional hybrid films for optical sensing applications and membranes is of utmost importance. In this work, we report the convenient and scalable preparation of self-crosslinking particle-based films derived by directed self-assembly of alkoxysilane-based cross-linkers as part of a core-shell particle architecture. The synthesis of well-designed monodisperse core-shell particles by emulsion polymerization is the basic prerequisite for subsequent particle processing via the melt-shear organization technique. In more detail, the core particles consist of polystyrene (PS) or poly(methyl methacrylate) (PMMA), while the comparably soft particle shell consists of poly(ethyl acrylate) (PEA) and different alkoxysilane-based poly(methacrylate)s. For hybrid film formation and convenient self-cross-linking, different alkyl groups at the siloxane moieties were investigated in detail by solid-state Magic-Angle Spinning Nuclear Magnetic Resonance (MAS, NMR) spectroscopy revealing different crosslinking capabilities, which strongly influence the properties of the core or shell particle films with respect to transparency and iridescent reflection colors. Furthermore, solid-state NMR spectroscopy and investigation of the thermal properties by differential scanning calorimetry (DSC) measurements allow for insights into the cross-linking capabilities prior to and after synthesis, as well as after the thermally and pressure-induced processing steps. Subsequently, free-standing and self-crosslinked particle-based films featuring excellent particle order are obtained by application of the melt-shear organization technique, as shown by microscopy (TEM, SEM). author: - first_name: S. full_name: Vowinkel, S. last_name: Vowinkel - first_name: S. full_name: Paul, S. last_name: Paul - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: M. full_name: Gallei, M. last_name: Gallei citation: ama: Vowinkel S, Paul S, Gutmann T, Gallei M. Free-Standing and Self-Crosslinkable Hybrid Films by Core-Shell Particle Design and Processing. Nanomaterials. 2017;7(11):390. doi:10.3390/nano7110390 apa: Vowinkel, S., Paul, S., Gutmann, T., & Gallei, M. (2017). Free-Standing and Self-Crosslinkable Hybrid Films by Core-Shell Particle Design and Processing. Nanomaterials, 7(11), 390. https://doi.org/10.3390/nano7110390 bibtex: '@article{Vowinkel_Paul_Gutmann_Gallei_2017, title={Free-Standing and Self-Crosslinkable Hybrid Films by Core-Shell Particle Design and Processing}, volume={7}, DOI={10.3390/nano7110390}, number={11}, journal={Nanomaterials}, author={Vowinkel, S. and Paul, S. and Gutmann, Torsten and Gallei, M.}, year={2017}, pages={390} }' chicago: 'Vowinkel, S., S. Paul, Torsten Gutmann, and M. Gallei. “Free-Standing and Self-Crosslinkable Hybrid Films by Core-Shell Particle Design and Processing.” Nanomaterials 7, no. 11 (2017): 390. https://doi.org/10.3390/nano7110390.' ieee: 'S. Vowinkel, S. Paul, T. Gutmann, and M. Gallei, “Free-Standing and Self-Crosslinkable Hybrid Films by Core-Shell Particle Design and Processing,” Nanomaterials, vol. 7, no. 11, p. 390, 2017, doi: 10.3390/nano7110390.' mla: Vowinkel, S., et al. “Free-Standing and Self-Crosslinkable Hybrid Films by Core-Shell Particle Design and Processing.” Nanomaterials, vol. 7, no. 11, 2017, p. 390, doi:10.3390/nano7110390. short: S. Vowinkel, S. Paul, T. Gutmann, M. Gallei, Nanomaterials 7 (2017) 390. date_created: 2026-02-07T16:15:23Z date_updated: 2026-02-17T16:12:54Z doi: 10.3390/nano7110390 extern: '1' intvolume: ' 7' issue: '11' keyword: - Materials Science - Science & Technology - Other Topics - solid-state nmr - spectroscopy - catalysts - colloidal crystals - colloids - cross-linking - elastomeric opal films - emulsion polymerization - gamma-methacryloxypropyltrimethoxysilane - hybrid films - melt-shear organization - nanoparticles - particle - photons - polymers - processing - self-assembly - transition language: - iso: eng page: '390' publication: Nanomaterials publication_identifier: issn: - 2079-4991 status: public title: Free-Standing and Self-Crosslinkable Hybrid Films by Core-Shell Particle Design and Processing type: journal_article user_id: '100715' volume: 7 year: '2017' ... --- _id: '63956' abstract: - lang: eng text: The synthesis of novel robust and stable iridium-based immobilized catalysts on silica-polymer hybrid materials (Si-PB-Ir) is described. These catalysts are characterized by a combination of 1D P-31 CP-MAS and 2D P-31-H-1 HETCOR and J-resolved multinuclear solid state NMR experiments. Different binding situations such as singly and multiply coordinated phosphines are identified. Density functional theory (DFT) calculations are performed to corroborate the interpretation of the experimental NMR data, in order to propose a structural model of the heterogenized catalysts. Finally, the catalytic activity of the Si-PB-Ir catalysts is investigated for the hydrogenation of styrene employing para-enriched hydrogen gas. author: - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: S. full_name: Alkhagani, S. last_name: Alkhagani - first_name: N. full_name: Rothermel, N. last_name: Rothermel - first_name: H. H. full_name: Limbach, H. H. last_name: Limbach - first_name: H. full_name: Breitzke, H. last_name: Breitzke - first_name: G. full_name: Buntkowsky, G. last_name: Buntkowsky citation: ama: Gutmann T, Alkhagani S, Rothermel N, Limbach HH, Breitzke H, Buntkowsky G. P-31-Solid-State NMR Characterization and Catalytic Hydrogenation Tests of Novel heterogenized Iridium-Catalysts. Zeitschrift Fur Physikalische Chemie-International Journal of Research in Physical Chemistry & Chemical Physics. 2017;231(3):653–669. doi:10.1515/zpch-2016-0837 apa: Gutmann, T., Alkhagani, S., Rothermel, N., Limbach, H. H., Breitzke, H., & Buntkowsky, G. (2017). P-31-Solid-State NMR Characterization and Catalytic Hydrogenation Tests of Novel heterogenized Iridium-Catalysts. Zeitschrift Fur Physikalische Chemie-International Journal of Research in Physical Chemistry & Chemical Physics, 231(3), 653–669. https://doi.org/10.1515/zpch-2016-0837 bibtex: '@article{Gutmann_Alkhagani_Rothermel_Limbach_Breitzke_Buntkowsky_2017, title={P-31-Solid-State NMR Characterization and Catalytic Hydrogenation Tests of Novel heterogenized Iridium-Catalysts}, volume={231}, DOI={10.1515/zpch-2016-0837}, number={3}, journal={Zeitschrift Fur Physikalische Chemie-International Journal of Research in Physical Chemistry & Chemical Physics}, author={Gutmann, Torsten and Alkhagani, S. and Rothermel, N. and Limbach, H. H. and Breitzke, H. and Buntkowsky, G.}, year={2017}, pages={653–669} }' chicago: 'Gutmann, Torsten, S. Alkhagani, N. Rothermel, H. H. Limbach, H. Breitzke, and G. Buntkowsky. “P-31-Solid-State NMR Characterization and Catalytic Hydrogenation Tests of Novel Heterogenized Iridium-Catalysts.” Zeitschrift Fur Physikalische Chemie-International Journal of Research in Physical Chemistry & Chemical Physics 231, no. 3 (2017): 653–669. https://doi.org/10.1515/zpch-2016-0837.' ieee: 'T. Gutmann, S. Alkhagani, N. Rothermel, H. H. Limbach, H. Breitzke, and G. Buntkowsky, “P-31-Solid-State NMR Characterization and Catalytic Hydrogenation Tests of Novel heterogenized Iridium-Catalysts,” Zeitschrift Fur Physikalische Chemie-International Journal of Research in Physical Chemistry & Chemical Physics, vol. 231, no. 3, pp. 653–669, 2017, doi: 10.1515/zpch-2016-0837.' mla: Gutmann, Torsten, et al. “P-31-Solid-State NMR Characterization and Catalytic Hydrogenation Tests of Novel Heterogenized Iridium-Catalysts.” Zeitschrift Fur Physikalische Chemie-International Journal of Research in Physical Chemistry & Chemical Physics, vol. 231, no. 3, 2017, pp. 653–669, doi:10.1515/zpch-2016-0837. short: T. Gutmann, S. Alkhagani, N. Rothermel, H.H. Limbach, H. Breitzke, G. Buntkowsky, Zeitschrift Fur Physikalische Chemie-International Journal of Research in Physical Chemistry & Chemical Physics 231 (2017) 653–669. date_created: 2026-02-07T15:35:41Z date_updated: 2026-02-17T16:18:04Z doi: 10.1515/zpch-2016-0837 extern: '1' intvolume: ' 231' issue: '3' keyword: - Chemistry - dynamic nuclear-polarization - solid-state nmr - DFT - heterogeneous catalysis - hydrido complexes - hydrogenation - immobilized catalyst - inorganic hybrid - iridium - materials - mesoporous - molecular-orbital methods - PHIP - phosphine complexes - reusable catalysts - silica - solid-state-NMR - wilkinsons catalyst language: - iso: eng page: 653–669 publication: Zeitschrift Fur Physikalische Chemie-International Journal of Research in Physical Chemistry & Chemical Physics publication_identifier: issn: - 0942-9352 status: public title: P-31-Solid-State NMR Characterization and Catalytic Hydrogenation Tests of Novel heterogenized Iridium-Catalysts type: journal_article user_id: '100715' volume: 231 year: '2017' ... --- _id: '63920' abstract: - lang: eng text: Coordinatively unsaturated sites (CUS) present a key feature of alumina based catalysts as they are believed to act as Lewis-acid sites in heterogeneously catalyzed reactions. In the present study, the direct observation of active species on a fluoride-doped aluminum oxide catalyst is demonstrated. This new fluoride-doped aluminum oxide exhibits strong Lewis-acid sites and superior catalytic activity as compared to gamma-Al2O3. To emphasize the labile state of Lewis-acid sites, two distinctive states of the catalysts surface are addressed using H-1-Al-27 cross polarization (CP) MAS NMR. On the one hand, the highly dehydrated and active state after calcination at 700 degrees C and on the other hand the rehydrated and catalytically inactive surface (produced by contact to air) are probed. These experiments revealed the presence of significant amounts of coordinatively unsaturated sites in the form of 4-and 5-fold coordinated Al-sites on the highly dehydrated surface. In contrast to this, the rehydrated sample exhibited a severely restructured surface caused by the chemisorption of H2O which is ’constituted in a manner that was proposed in earlier models for gamma-Al2O3 surfaces. author: - first_name: L. full_name: Ahrem, L. last_name: Ahrem - first_name: G. full_name: Scholz, G. last_name: Scholz - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: B. full_name: Calvo, B. last_name: Calvo - first_name: G. full_name: Buntkowsky, G. last_name: Buntkowsky - first_name: E. full_name: Kemnitz, E. last_name: Kemnitz citation: ama: Ahrem L, Scholz G, Gutmann T, Calvo B, Buntkowsky G, Kemnitz E. Direct Observation of Coordinatively Unsaturated Sites on the Surface of a Fluoride-Doped Alumina Catalyst. Journal of Physical Chemistry C. 2017;121(22):12206–12213. doi:10.1021/acs.jpcc.7b02535 apa: Ahrem, L., Scholz, G., Gutmann, T., Calvo, B., Buntkowsky, G., & Kemnitz, E. (2017). Direct Observation of Coordinatively Unsaturated Sites on the Surface of a Fluoride-Doped Alumina Catalyst. Journal of Physical Chemistry C, 121(22), 12206–12213. https://doi.org/10.1021/acs.jpcc.7b02535 bibtex: '@article{Ahrem_Scholz_Gutmann_Calvo_Buntkowsky_Kemnitz_2017, title={Direct Observation of Coordinatively Unsaturated Sites on the Surface of a Fluoride-Doped Alumina Catalyst}, volume={121}, DOI={10.1021/acs.jpcc.7b02535}, number={22}, journal={Journal of Physical Chemistry C}, author={Ahrem, L. and Scholz, G. and Gutmann, Torsten and Calvo, B. and Buntkowsky, G. and Kemnitz, E.}, year={2017}, pages={12206–12213} }' chicago: 'Ahrem, L., G. Scholz, Torsten Gutmann, B. Calvo, G. Buntkowsky, and E. Kemnitz. “Direct Observation of Coordinatively Unsaturated Sites on the Surface of a Fluoride-Doped Alumina Catalyst.” Journal of Physical Chemistry C 121, no. 22 (2017): 12206–12213. https://doi.org/10.1021/acs.jpcc.7b02535.' ieee: 'L. Ahrem, G. Scholz, T. Gutmann, B. Calvo, G. Buntkowsky, and E. Kemnitz, “Direct Observation of Coordinatively Unsaturated Sites on the Surface of a Fluoride-Doped Alumina Catalyst,” Journal of Physical Chemistry C, vol. 121, no. 22, pp. 12206–12213, 2017, doi: 10.1021/acs.jpcc.7b02535.' mla: Ahrem, L., et al. “Direct Observation of Coordinatively Unsaturated Sites on the Surface of a Fluoride-Doped Alumina Catalyst.” Journal of Physical Chemistry C, vol. 121, no. 22, 2017, pp. 12206–12213, doi:10.1021/acs.jpcc.7b02535. short: L. Ahrem, G. Scholz, T. Gutmann, B. Calvo, G. Buntkowsky, E. Kemnitz, Journal of Physical Chemistry C 121 (2017) 12206–12213. date_created: 2026-02-07T08:56:18Z date_updated: 2026-02-17T16:19:24Z doi: 10.1021/acs.jpcc.7b02535 extern: '1' intvolume: ' 121' issue: '22' keyword: - al-27 nmr - characterization - Chemistry - cross-polarization - dynamic nuclear-polarization - eta-alumina - gamma-alumina - hydroxy fluorides - ions - Materials Science - pentacoordinated al3+ - Science & Technology - Other Topics - solid-state nmr - spectroscopic - structural insights language: - iso: eng page: 12206–12213 publication: Journal of Physical Chemistry C publication_identifier: issn: - 1932-7447 status: public title: Direct Observation of Coordinatively Unsaturated Sites on the Surface of a Fluoride-Doped Alumina Catalyst type: journal_article user_id: '100715' volume: 121 year: '2017' ... --- _id: '64039' abstract: - lang: eng text: The preparation of hierarchical and sophisticated particle architectures for mimicking structural colors known from nature still remains a challenge. In this study, the preparation of novel opal and double-inverse opal films based on thermally treated metallopolymer core particles with a silica shell is described. Thermal treatment leads to the formation of magnetic nanorattle-type particles. The main challenge of artificial particles is to ensure sufficient dispersibility after several synthetic steps. Especially silica particles providing surface hydroxyl groups tend to sinter at high temperatures leading to agglomeration. We present the introduction of trimethyl ethoxy silane (TMES) as an excellent functionalization reagent as the key reaction step. The necessity and success of functionalization are investigated by transmission electron microscopy (TEM) and zeta potential measurements. Importantly, solid state NMR techniques are employed to gain deeper insights into the chemical structure of the surface-attached reagent. Finally, by this convenient functionalization the preparation of elastomeric opal films and double-inverse opal films is proven successful revealing excellent optical film properties. Moreover, magnetic properties of these novel films are investigated by using magnetic force microscopy (MFM). The herein established route is expected to pave the way for the preparation of a variety of advanced and stimuli-responsive optical materials. author: - first_name: D. full_name: Scheid, D. last_name: Scheid - first_name: D. full_name: Stock, D. last_name: Stock - first_name: T. full_name: Winter, T. last_name: Winter - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: C. full_name: Dietz, C. last_name: Dietz - first_name: M. full_name: Gallei, M. last_name: Gallei citation: ama: Scheid D, Stock D, Winter T, Gutmann T, Dietz C, Gallei M. The pivotal step of nanoparticle functionalization for the preparation of functional and magnetic hybrid opal films. Journal of Materials Chemistry C. 2016;4(11):2187–2196. doi:10.1039/c5tc04388c apa: Scheid, D., Stock, D., Winter, T., Gutmann, T., Dietz, C., & Gallei, M. (2016). The pivotal step of nanoparticle functionalization for the preparation of functional and magnetic hybrid opal films. Journal of Materials Chemistry C, 4(11), 2187–2196. https://doi.org/10.1039/c5tc04388c bibtex: '@article{Scheid_Stock_Winter_Gutmann_Dietz_Gallei_2016, title={The pivotal step of nanoparticle functionalization for the preparation of functional and magnetic hybrid opal films}, volume={4}, DOI={10.1039/c5tc04388c}, number={11}, journal={Journal of Materials Chemistry C}, author={Scheid, D. and Stock, D. and Winter, T. and Gutmann, Torsten and Dietz, C. and Gallei, M.}, year={2016}, pages={2187–2196} }' chicago: 'Scheid, D., D. Stock, T. Winter, Torsten Gutmann, C. Dietz, and M. Gallei. “The Pivotal Step of Nanoparticle Functionalization for the Preparation of Functional and Magnetic Hybrid Opal Films.” Journal of Materials Chemistry C 4, no. 11 (2016): 2187–2196. https://doi.org/10.1039/c5tc04388c.' ieee: 'D. Scheid, D. Stock, T. Winter, T. Gutmann, C. Dietz, and M. Gallei, “The pivotal step of nanoparticle functionalization for the preparation of functional and magnetic hybrid opal films,” Journal of Materials Chemistry C, vol. 4, no. 11, pp. 2187–2196, 2016, doi: 10.1039/c5tc04388c.' mla: Scheid, D., et al. “The Pivotal Step of Nanoparticle Functionalization for the Preparation of Functional and Magnetic Hybrid Opal Films.” Journal of Materials Chemistry C, vol. 4, no. 11, 2016, pp. 2187–2196, doi:10.1039/c5tc04388c. short: D. Scheid, D. Stock, T. Winter, T. Gutmann, C. Dietz, M. Gallei, Journal of Materials Chemistry C 4 (2016) 2187–2196. date_created: 2026-02-07T16:09:09Z date_updated: 2026-02-17T16:13:25Z doi: 10.1039/c5tc04388c extern: '1' intvolume: ' 4' issue: '11' keyword: - Materials Science - silica - Physics - nmr - colloidal photonic crystals - light - polymerization - solids - structural color - thermo language: - iso: eng page: 2187–2196 publication: Journal of Materials Chemistry C publication_identifier: issn: - 2050-7526 status: public title: The pivotal step of nanoparticle functionalization for the preparation of functional and magnetic hybrid opal films type: journal_article user_id: '100715' volume: 4 year: '2016' ... --- _id: '63963' abstract: - lang: eng text: A novel heterogeneous dirhodium catalyst has been synthesized. This stable catalyst is constructed from dirhodium acetate dimer (Rh2(OAc)4) units, which are covalently linked to amine- and carboxyl-bifunctionalized mesoporous silica (SBA-15NH2COOH). It shows good efficiency in catalyzing the cyclopropanation reaction of styrene and ethyl diazoacetate (EDA) forming cis- and trans-1-ethoxycarbonyl-2-phenylcyclopropane. To characterize the structure of this catalyst and to confirm the successful immobilization, heteronuclear solid-state NMR experiments have been performed. The high application potential of dynamic nuclear polarization (DNP) NMR for the analysis of binding sites in this novel catalyst is demonstrated. Signal-enhanced 13C CP MAS and 15N CP MAS techniques have been employed to detect different carboxyl and amine binding sites in natural abundance on a fast time scale. The interpretation of the experimental chemical shift values for different binding sites has been corroborated by quantum chemical calculations on dirhodium model complexes. author: - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: Jiquan full_name: Liu, Jiquan last_name: Liu - first_name: Niels full_name: Rothermel, Niels last_name: Rothermel - first_name: Yeping full_name: Xu, Yeping last_name: Xu - first_name: Eva full_name: Jaumann, Eva last_name: Jaumann - first_name: Mayke full_name: Werner, Mayke last_name: Werner - first_name: Hergen full_name: Breitzke, Hergen last_name: Breitzke - first_name: Snorri T. full_name: Sigurdsson, Snorri T. last_name: Sigurdsson - first_name: Gerd full_name: Buntkowsky, Gerd last_name: Buntkowsky citation: ama: 'Gutmann T, Liu J, Rothermel N, et al. Natural Abundance 15N NMR by Dynamic Nuclear Polarization: Fast Analysis of Binding Sites of a Novel Amine-Carboxyl-Linked Immobilized Dirhodium Catalyst. Chemistry A European Journal. 2015;21(9):3798–3805. doi:10.1002/chem.201405043' apa: 'Gutmann, T., Liu, J., Rothermel, N., Xu, Y., Jaumann, E., Werner, M., Breitzke, H., Sigurdsson, S. T., & Buntkowsky, G. (2015). Natural Abundance 15N NMR by Dynamic Nuclear Polarization: Fast Analysis of Binding Sites of a Novel Amine-Carboxyl-Linked Immobilized Dirhodium Catalyst. Chemistry A European Journal, 21(9), 3798–3805. https://doi.org/10.1002/chem.201405043' bibtex: '@article{Gutmann_Liu_Rothermel_Xu_Jaumann_Werner_Breitzke_Sigurdsson_Buntkowsky_2015, title={Natural Abundance 15N NMR by Dynamic Nuclear Polarization: Fast Analysis of Binding Sites of a Novel Amine-Carboxyl-Linked Immobilized Dirhodium Catalyst}, volume={21}, DOI={10.1002/chem.201405043}, number={9}, journal={Chemistry A European Journal}, publisher={WILEY-VCH Verlag}, author={Gutmann, Torsten and Liu, Jiquan and Rothermel, Niels and Xu, Yeping and Jaumann, Eva and Werner, Mayke and Breitzke, Hergen and Sigurdsson, Snorri T. and Buntkowsky, Gerd}, year={2015}, pages={3798–3805} }' chicago: 'Gutmann, Torsten, Jiquan Liu, Niels Rothermel, Yeping Xu, Eva Jaumann, Mayke Werner, Hergen Breitzke, Snorri T. Sigurdsson, and Gerd Buntkowsky. “Natural Abundance 15N NMR by Dynamic Nuclear Polarization: Fast Analysis of Binding Sites of a Novel Amine-Carboxyl-Linked Immobilized Dirhodium Catalyst.” Chemistry A European Journal 21, no. 9 (2015): 3798–3805. https://doi.org/10.1002/chem.201405043.' ieee: 'T. Gutmann et al., “Natural Abundance 15N NMR by Dynamic Nuclear Polarization: Fast Analysis of Binding Sites of a Novel Amine-Carboxyl-Linked Immobilized Dirhodium Catalyst,” Chemistry A European Journal, vol. 21, no. 9, pp. 3798–3805, 2015, doi: 10.1002/chem.201405043.' mla: 'Gutmann, Torsten, et al. “Natural Abundance 15N NMR by Dynamic Nuclear Polarization: Fast Analysis of Binding Sites of a Novel Amine-Carboxyl-Linked Immobilized Dirhodium Catalyst.” Chemistry A European Journal, vol. 21, no. 9, WILEY-VCH Verlag, 2015, pp. 3798–3805, doi:10.1002/chem.201405043.' short: T. Gutmann, J. Liu, N. Rothermel, Y. Xu, E. Jaumann, M. Werner, H. Breitzke, S.T. Sigurdsson, G. Buntkowsky, Chemistry A European Journal 21 (2015) 3798–3805. date_created: 2026-02-07T15:38:07Z date_updated: 2026-02-17T16:17:50Z doi: 10.1002/chem.201405043 extern: '1' intvolume: ' 21' issue: '9' keyword: - heterogeneous catalysis - immobilized catalyst - dynamic nuclear polarization - hyperpolarization - NMR spectroscopy language: - iso: eng page: 3798–3805 publication: Chemistry A European Journal publisher: WILEY-VCH Verlag status: public title: 'Natural Abundance 15N NMR by Dynamic Nuclear Polarization: Fast Analysis of Binding Sites of a Novel Amine-Carboxyl-Linked Immobilized Dirhodium Catalyst' type: journal_article user_id: '100715' volume: 21 year: '2015' ... --- _id: '64055' abstract: - lang: eng text: A program for iterative fitting procedures to determine the NMR parameters from 51V solid-state MAS NMR spectra was developed. It contains options to use genetic algorithms and downhill-simplex optimizing procedures to extract the optimal parameter sets, which describe our spectra. As computational kernel the SIMPSON program is employed. Other kernels like SPINEVOLUTION are easily incorporable. The algorithms are checked for their suitability for the present optimization problem and optimal simulation conditions are determined, with the focus on minimal processing time. The procedure leads to a very good agreement between experimental and simulated spectra in a passable period of time. First results for spectra of model compounds for the active site of vanadium haloperoxidases are presented. author: - first_name: Maria full_name: Waechtler, Maria last_name: Waechtler - first_name: Annika full_name: Schweitzer, Annika last_name: Schweitzer - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: Hergen full_name: Breitzke, Hergen last_name: Breitzke - first_name: Gerd full_name: Buntkowsky, Gerd last_name: Buntkowsky citation: ama: Waechtler M, Schweitzer A, Gutmann T, Breitzke H, Buntkowsky G. Efficient analysis of 51V solid-state MAS NMR spectra using genetic algorithms. Solid State Nuclear Magnetic Resonance. 2009;35(1):37–48. doi:10.1016/j.ssnmr.2008.11.003 apa: Waechtler, M., Schweitzer, A., Gutmann, T., Breitzke, H., & Buntkowsky, G. (2009). Efficient analysis of 51V solid-state MAS NMR spectra using genetic algorithms. Solid State Nuclear Magnetic Resonance, 35(1), 37–48. https://doi.org/10.1016/j.ssnmr.2008.11.003 bibtex: '@article{Waechtler_Schweitzer_Gutmann_Breitzke_Buntkowsky_2009, title={Efficient analysis of 51V solid-state MAS NMR spectra using genetic algorithms}, volume={35}, DOI={10.1016/j.ssnmr.2008.11.003}, number={1}, journal={Solid State Nuclear Magnetic Resonance}, author={Waechtler, Maria and Schweitzer, Annika and Gutmann, Torsten and Breitzke, Hergen and Buntkowsky, Gerd}, year={2009}, pages={37–48} }' chicago: 'Waechtler, Maria, Annika Schweitzer, Torsten Gutmann, Hergen Breitzke, and Gerd Buntkowsky. “Efficient Analysis of 51V Solid-State MAS NMR Spectra Using Genetic Algorithms.” Solid State Nuclear Magnetic Resonance 35, no. 1 (2009): 37–48. https://doi.org/10.1016/j.ssnmr.2008.11.003.' ieee: 'M. Waechtler, A. Schweitzer, T. Gutmann, H. Breitzke, and G. Buntkowsky, “Efficient analysis of 51V solid-state MAS NMR spectra using genetic algorithms,” Solid State Nuclear Magnetic Resonance, vol. 35, no. 1, pp. 37–48, 2009, doi: 10.1016/j.ssnmr.2008.11.003.' mla: Waechtler, Maria, et al. “Efficient Analysis of 51V Solid-State MAS NMR Spectra Using Genetic Algorithms.” Solid State Nuclear Magnetic Resonance, vol. 35, no. 1, 2009, pp. 37–48, doi:10.1016/j.ssnmr.2008.11.003. short: M. Waechtler, A. Schweitzer, T. Gutmann, H. Breitzke, G. Buntkowsky, Solid State Nuclear Magnetic Resonance 35 (2009) 37–48. date_created: 2026-02-07T16:15:57Z date_updated: 2026-02-17T16:12:50Z doi: 10.1016/j.ssnmr.2008.11.003 extern: '1' intvolume: ' 35' issue: '1' keyword: - 51V MAS NMR spectroscopy - Genetic algorithms - Iterative fitting procedures - Model complexes for vanadium haloperoxidases language: - iso: eng page: 37–48 publication: Solid State Nuclear Magnetic Resonance status: public title: Efficient analysis of 51V solid-state MAS NMR spectra using genetic algorithms type: journal_article user_id: '100715' volume: 35 year: '2009' ... --- _id: '63951' abstract: - lang: eng text: The parameters describing the quadrupolar and CSA interactions of 51V solid-state MAS NMR investigations of model complexes mimicking vanadoenzymes as well as vanadium containing catalysts and enzyme complexes are interpreted with respect to the chemical structure. The interpretation is based on the data of 15 vanadium complexes including two new complexes with previously unpublished data and 13 complexes with data previously published by us. Correlations between the chemical structure and the 51V solid-state NMR data of this class of compounds have been established. Especially for the isotropic chemical shift δ iso and the chemical shift anisotropy δ σ , correlations with specific structural features like the coordination number of the vanadium atom, the number of coordinating nitrogens, the number of oxygen atoms and the chemical surrounding of the complex could be established for these compounds. Moreover, quantitative correlations between the solid-state NMR parameters and specific bond angles and bond lengths have been obtained. Our results can be of particular interest for future investigations concerning the structure and the mode of action of related vanadoenzymes and vanadate protein assemblies, including the use of vanadate adducts as transition state analogs for phosphate metabolizing systems. author: - first_name: Annika full_name: Fenn, Annika last_name: Fenn - first_name: Maria full_name: Wächtler, Maria last_name: Wächtler - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: Hergen full_name: Breitzke, Hergen last_name: Breitzke - first_name: Axel full_name: Buchholz, Axel last_name: Buchholz - first_name: Ines full_name: Lippold, Ines last_name: Lippold - first_name: Winfried full_name: Plass, Winfried last_name: Plass - first_name: Gerd full_name: Buntkowsky, Gerd last_name: Buntkowsky citation: ama: Fenn A, Wächtler M, Gutmann T, et al. Correlations between 51V solid-state NMR parameters and chemical structure of vanadium (V) complexes as models for related metalloproteins and catalysts. Solid State Nuclear Magnetic Resonance. 2009;36(4):192–201. doi:10.1016/j.ssnmr.2009.11.003 apa: Fenn, A., Wächtler, M., Gutmann, T., Breitzke, H., Buchholz, A., Lippold, I., Plass, W., & Buntkowsky, G. (2009). Correlations between 51V solid-state NMR parameters and chemical structure of vanadium (V) complexes as models for related metalloproteins and catalysts. Solid State Nuclear Magnetic Resonance, 36(4), 192–201. https://doi.org/10.1016/j.ssnmr.2009.11.003 bibtex: '@article{Fenn_Wächtler_Gutmann_Breitzke_Buchholz_Lippold_Plass_Buntkowsky_2009, title={Correlations between 51V solid-state NMR parameters and chemical structure of vanadium (V) complexes as models for related metalloproteins and catalysts}, volume={36}, DOI={10.1016/j.ssnmr.2009.11.003}, number={4}, journal={Solid State Nuclear Magnetic Resonance}, author={Fenn, Annika and Wächtler, Maria and Gutmann, Torsten and Breitzke, Hergen and Buchholz, Axel and Lippold, Ines and Plass, Winfried and Buntkowsky, Gerd}, year={2009}, pages={192–201} }' chicago: 'Fenn, Annika, Maria Wächtler, Torsten Gutmann, Hergen Breitzke, Axel Buchholz, Ines Lippold, Winfried Plass, and Gerd Buntkowsky. “Correlations between 51V Solid-State NMR Parameters and Chemical Structure of Vanadium (V) Complexes as Models for Related Metalloproteins and Catalysts.” Solid State Nuclear Magnetic Resonance 36, no. 4 (2009): 192–201. https://doi.org/10.1016/j.ssnmr.2009.11.003.' ieee: 'A. Fenn et al., “Correlations between 51V solid-state NMR parameters and chemical structure of vanadium (V) complexes as models for related metalloproteins and catalysts,” Solid State Nuclear Magnetic Resonance, vol. 36, no. 4, pp. 192–201, 2009, doi: 10.1016/j.ssnmr.2009.11.003.' mla: Fenn, Annika, et al. “Correlations between 51V Solid-State NMR Parameters and Chemical Structure of Vanadium (V) Complexes as Models for Related Metalloproteins and Catalysts.” Solid State Nuclear Magnetic Resonance, vol. 36, no. 4, 2009, pp. 192–201, doi:10.1016/j.ssnmr.2009.11.003. short: A. Fenn, M. Wächtler, T. Gutmann, H. Breitzke, A. Buchholz, I. Lippold, W. Plass, G. Buntkowsky, Solid State Nuclear Magnetic Resonance 36 (2009) 192–201. date_created: 2026-02-07T15:33:58Z date_updated: 2026-02-17T16:18:21Z doi: 10.1016/j.ssnmr.2009.11.003 extern: '1' intvolume: ' 36' issue: '4' keyword: - 51V NMR - Cis-dioxovanadium (v) complex - Model system - Vanadate language: - iso: eng page: 192–201 publication: Solid State Nuclear Magnetic Resonance status: public title: Correlations between 51V solid-state NMR parameters and chemical structure of vanadium (V) complexes as models for related metalloproteins and catalysts type: journal_article user_id: '100715' volume: 36 year: '2009' ...