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4. Metal-Organic Framework Breathing in Electric Field: A Theoretical Study

Author

Kolesnikov, Andrei L., Budkov, Yury A., Möllmer, Jens, Kiselev, Michael G., and Gläser, Roger

Subjects
Condensed Matter - Soft Condensed Matter
Abstract

In this manuscript, we study the electrically induced breathing of Metal-Organic Framework (MOF) within a 2D lattice model. The Helmholtz free energy of the MOF in electric field consists of two parts: the electrostatic energy of the dielectric body in the external electric field and elastic energy of the framework. The first contribution is calculated from the first principles of statistical mechanics with an account of MOF symmetry. By minimizing the obtained free energy and solving the resulting system of equations, we obtain the local electric field and the parameter of the unit cell (angle $\alpha$). The paper also studies the cross-section area of the unit cell and the polarization as functions of the external electric field. We obtain the hysteresis in the region of the structural transition of the framework. Our results are in qualitative agreement with the literature data of the molecular dynamics (MD) simulation of MIL-53(Cr)., Comment: Accepted in Journal of Physical Chemistry C

Published
2019
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14. Lignin‑Based Composite Materials for Photocatalysis and Photovoltaics

Author

Khan, Ayesha, Colmenares, Juan Carlos, Gläser, Roger, Olivucci, Massimo, Editor-in-Chief, Wong, Wai-Yeung, Editor-in-Chief, Bayley, Hagan, Series Editor, Hughes, Greg, Series Editor, Hunter, Christopher A., Series Editor, Hwang, Seong-Ju, Series Editor, Ishihara, Kazuaki, Series Editor, Kirchner, Barbara, Series Editor, Krische, Michael J., Series Editor, Larsen, Delmar, Series Editor, Lehn, Jean-Marie, Series Editor, Luque, Rafael, Series Editor, Siegel, Jay S., Series Editor, Thiem, Joachim, Series Editor, Venturi, Margherita, Series Editor, Wong, Chi-Huey, Series Editor, Wong, Henry N.C., Series Editor, Yam, Vivian Wing-Wah, Series Editor, Yan, Chunhua, Series Editor, You, Shu-Li, Series Editor, Serrano, Luis, editor, and Sels, Bert F., editor

Published
2020
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18. Porosity and Structure of Hierarchically Porous Ni/Al₂O₃ Catalysts for CO₂ Methanation

Author

Weber, Sebastian, Abel, Ken L., Zimmermann, Ronny T., Huang, Xiaohui, Bremer, Jens, Rihko-Struckmann, Liisa K., Batey, Darren, Cipiccia, Silvia, Titus, Juliane, Poppitz, David, Kübel, Christian, Sundmacher, Kai, Gläser, Roger, Sheppard, Thomas L., Weber, Sebastian, Abel, Ken L., Zimmermann, Ronny T., Huang, Xiaohui, Bremer, Jens, Rihko-Struckmann, Liisa K., Batey, Darren, Cipiccia, Silvia, Titus, Juliane, Poppitz, David, Kübel, Christian, Sundmacher, Kai, Gläser, Roger, and Sheppard, Thomas L.

Abstract

CO₂ methanation is often performed on Ni/Al₂O₃ catalysts, which can suffer from mass transport limitations and, therefore, decreased efficiency. Here we show the application of a hierarchically porous Ni/Al₂O₃ catalyst for methanation of CO₂. The material has a well-defined and connected meso- and macropore structure with a total porosity of 78%. The pore structure was thoroughly studied with conventional methods, i.e., N₂ sorption, Hg porosimetry, and He pycnometry, and advanced imaging techniques, i.e., electron tomography and ptychographic X-ray computed tomography. Tomography can quantify the pore system in a manner that is not possible using conventional porosimetry. Macrokinetic simulations were performed based on the measures obtained by porosity analysis. These show the potential benefit of enhanced mass-transfer properties of the hierarchical pore system compared to a pure mesoporous catalyst at industrially relevant conditions. Besides the investigation of the pore system, the catalyst was studied by Rietveld refinement, diffuse reflectance ultraviolet-visible (DRUV/vis) spectroscopy, and H₂-temperature programmed reduction (TPR), showing a high reduction temperature required for activation due to structural incorporation of Ni into the transition alumina. The reduced hierarchically porous Ni/Al₂O₃ catalyst is highly active in CO₂ methanation, showing comparable conversion and selectivity for CH₄ to an industrial reference catalyst.

Published
2024

20. Post-Synthetically Treated ERI and SSZ-13 Zeolites Modified with Copper as Catalysts for NH 3 -SCR-DeNO x.

Author

Robles, Alejandro Mollá, Deplano, Gabriele, Góra-Marek, Kinga, Rotko, Marek, Wach, Anna, Lukman, Muhammad Fernadi, Bertmer, Marko, Signorile, Matteo, Bordiga, Silvia, Pöppl, Andreas, Gläser, Roger, and Jabłońska, Magdalena

Subjects
COPPER catalysts, COPPER, CATALYTIC activity, ULTRAVIOLET-visible spectroscopy, ZEOLITES
Abstract

ERI and SSZ-13 were subjected to post-synthetic treatments (depending on the zeolite topology) to create micro-/mesoporous materials. The results in terms of NH3-SCR-DeNOx show that the applied treatments improved the catalytic activity of the Cu-containing ERI-based materials; however, the NO conversion did not vary for the different materials treated with NaOH or NaOH/HNO3. For the micro-/mesoporous Cu-containing SSZ-13, a lower NO conversion in NH3-SCR-DeNOx was observed. Thus, our findings challenge the current paradigm of enhanced activity of micro-/mesoporous catalysts in NH3-SCR-DeNOx. The modification of the supports results in the presence of different amounts and kinds of copper species (especially isolated Cu2+ and aggregated Cu species) in the case of ERI- and SSZ-13-based samples. The present copper species further differentiate the formation of reactive reaction intermediates. Our studies show that besides the μ-η2,η2-peroxo dicopper(II) complexes (verified by in situ DR UV-Vis spectroscopy), copper nitrates (evidenced by in situ FT-IR spectroscopy) also act as reactive intermediates in these catalytic systems. [ABSTRACT FROM AUTHOR]

Published
2024
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26. Special Collection: Catalysts and Reactors under Dynamic Conditions for Energy Storage and Conversion.

Author

Klag, Linda, Gläser, Roger, Krewer, Ulrike, Reuter, Karsten, and Grunwaldt, Jan‐Dierk

Subjects
*PHYSICAL & theoretical chemistry, *SUSTAINABILITY, *PHYSICAL sciences, *HETEROGENEOUS catalysis, *CHEMICAL processes, *METHANATION
Abstract

This document is an editorial from the journal ChemCatChem titled "Special Collection: Catalysts and Reactors under Dynamic Conditions for Energy Storage and Conversion." The editorial discusses the importance of power-to-chemical, power-to-fuel, and power-to-gas processes in decarbonizing the industry and achieving CO2 neutrality. It highlights the challenges of storing large amounts of fluctuating renewable energy and the role of catalysis in transforming electrical energy and low-energy molecules into high-energy reactive molecules. The editorial emphasizes the need for interdisciplinary scientific approaches and the development of new materials and catalytic processes. The document also mentions a topical collection of research articles on the dynamics of catalysts and reactors, as well as upcoming conferences on the topic. [Extracted from the article]

Published
2024
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29. OSDA-Free Seeded Cu-Containing ZSM-5 Applied for NH3–SCR-DeNOx

Author

Jabłońska, Magdalena, primary, Palčić, Ana, additional, Lukman, Muhammad Fernadi, additional, Wach, Anna, additional, Bertmer, Marko, additional, Poppitz, David, additional, Denecke, Reinhard, additional, Wu, Xiaochao, additional, Simon, Ulrich, additional, Pöppl, Andreas, additional, and Gläser, Roger, additional

Published
2023
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