In situ electron microscopy of catalyst nanoparticles
Understanding the physicochemical properties of heterogeneous catalysts is a prerequisite for establishing so-called “structure–activity/property” relationships, and it is therefore imperative for catalyst development and elucidating reaction mechanisms on an atomic level. In situ electron microscopy offers great opportunities for the study of catalyst nanoparticle systems. By using micro-electromechanical systems (MEMS)-based TEM specimen holders it is possible to record the atomic and/or electronic structures of materials, including the evolution of their size and shape, in real time during electrochemical reactions and growth processes at elevated temperature and/or in gas or liquid environments.
The Ernst Ruska-Centre has a wide variety of MEMS-based TEM specimen holders, including DENSsolutions single and double tilt heating and biasing holders, a combined heating and cooling holder and a combined gas reaction and heating holder. The DENSsolutions “Climate” in situ TEM gas and heating holder provides a high pressure (1 bar) gas environment at temperatures of up to 1000 K inside a nano-reactor, enabling atomic resolution characterization of solid-gas reactions in real time. Furthermore, we us dedicated instruments like the environmental Hitachi HF5000 scanning transmission electron microscope. By means of a gas mixing station, different gases (nitrogen, oxygen, synth. air, CO2and hydrogen) and their mixtures can be introduced directly into the column at a maximum pressure of 16 Pascal. A Hitachi in situ liquid cell holder is available for electrochemical experiments.
For more details please refer to the papers:
Meise, A.; Heggen, M.; Dunin-Borkowski, R. E.; Armbrüster, M. In Situ Scanning Transmission Electron Microscopy Calcination of Palladium Nitrate Supported on Zinc Oxide. Small Science 2024, 4 (8), 2400048. https://doi.org/10.1002/smsc.202400048
Vennewald, M.; Sackers, N. M.; Iemhoff, A.; Kappel, I.; Weidenthaler, C.; Meise, A.; Heggen, M.; Dunin-Borkowski, R. E.; Keenan, L.; Palkovits, R. Dynamics of Palladium Single-Atoms on Graphitic Carbon Nitride during Ethylene Hydrogenation. Journal of Catalysis 2023, 421, 134–144. https://doi.org/10.1016/j.jcat.2023.03.011.
MacArthur, K. E.; Polani, S.; Klingenhof, M.; Gumbiowski, N.; Möller, T.; Paciok, P.; Kang, J.; Epple, M.; Basak, S.; Eichel, R.-A.; Strasser, P.; Dunin-Borkowski, R. E.; Heggen, M. Post-Synthesis Heat Treatment of Doped PtNi-Alloy Fuel-Cell Catalyst Nanoparticles Studied by In-Situ Electron Microscopy. ACS Appl. Energy Mater. 2023, 6 (11), 5959–5967. https://doi.org/10.1021/acsaem.3c00405.
Heggen, M.; Feuerbacher, M.; Dunin-Borkowski, R. E. Direct Observation of Dislocation Motion in the Complex Alloy T-Al-Mn-Fe Using in-Situ Transmission Electron Microscopy. Materials Research Letters 2023, 11 (5), 367–373. https://doi.org/10.1080/21663831.2022.2155492.
Karatzia, A.; Loza, K.; Prymak, O.; Heggen, M.; Epple, M. Thermal Behavior of Silver–Gold Core–Shell Nanocubes: In Situ X-Ray Diffraction and In Situ Electron Microscopy (SEM and TEM). J. Phys. Chem. C 2023, 127 (39), 19620–19628. https://doi.org/10.1021/acs.jpcc.3c04578.
Cao, P.; Tang, P.; Bekheet, M. F.; Du, H.; Yang, L.; Haug, L.; Gili, A.; Bischoff, B.; Gurlo, A.; Kunz, M.; Dunin-Borkowski, R. E.; Penner, S.; Heggen, M. Atomic-Scale Insights into Nickel Exsolution on LaNiO3 Catalysts via In Situ Electron Microscopy. J. Phys. Chem. C 2022, 126 (1), 786–796. https://doi.org/10.1021/acs.jpcc.1c09257.
Pappert, K.; Loza, K.; Shviro, M.; Hagemann, U.; Heggen, M.; Dunin-Borkowski, R. E.; Schierholz, R.; Maeda, T.; Kaneko, K.; Epple, M. Nanoscopic Porous Iridium/Iridium Dioxide Superstructures (15 Nm): Synthesis and Thermal Conversion by In Situ Transmission Electron Microscopy. Chemistry – A European Journal 2019, 25 (47), 11048–11057. https://doi.org/10.1002/chem.201901623.
Contact:
Dr. Marc Heggen
Phone: +49 2461 61-9479
E-Mail: m.heggen@fz-juelich.de