The recently published study of the X-ray microscopy group of Dr. Thomas Sheppard on revealing the location of coke species in single catalysts grains was highlighted in the Annual Review 2021/22 of the Diamond Light Source. The research performed by Sebastian Weber and co-authors was originally published as “Hard X-Ray Nanotomography for 3D Analysis of Coking in Nickel-Based Catalysts” in Angew. Chem. Int. Ed. The study showcases the emerging possibility of Ptychographic X-ray Computed Tomography (PXCT) – a modern X-ray nanotomography method – to locate coke species relevant for catalyst deactivation in single catalyst grains. The Diamond Light Source highlights in its Annual Review a selected research result for each of its beamlines.

Next-generation catalysts play a key role for the use of sustainable fuels in aviation. Improving such catalysts is the goal of the German-South African consortium CARE-O-SENE, in which KIT is involved. In May 2022, German Chancellor Olaf Scholz announced the start of the project in Johannesburg. The international catalysis company Sasol and the Helmholtz-Zentrum Berlin (HZB) are coordinating the project, which is supported by the German Federal Ministry of Education and Research (BMBF).  The goal is to accelerate the economic production of green kerosene based on Fischer-Tropsch technology. A total of six institutions from Germany and South Africa are involved in CARE-O-SENE. In addition to Sasol, HZB, and KIT, these are the University of Cape Town, with which KIT cooperates closely, Ineratec GmbH, a KIT spin-off, and the Fraunhofer Institute for Ceramic Technologies and Systems. KIT researchers will investigate the structural change of catalysts at the KIT synchrotron radiation source and at other X-ray radiation sources, supported by theoretical modeling and sustainability calculations.

AKG

The Grunwaldt group had a productive and successful trip to "Jahrestreffen Deutscher Katalytiker" in Weimar with talks and posters. Besides inspiring discussions, multiple group members were awarded prizes for their contributions. Congratulations to Mariam Schulte for a poster prize, Linda Klag for a poster workshop award and Erisa Saraci for the "Roter Löwe"!

DIPARTIMENTO DI SCIENZE CHIMICHE

Prof. Grunwaldt was invited as visiting professor to the university in Padova. He gave a course for PhD and Postdoc students on the applications of synchrotron radiation under dynamic/operando conditions in heterogeneous catalysis. The course led to interesting discussions and we are looking forward to further collaborations.

Dr. Ziliang Chen/HZB

Synchrotron radiation shows us how materials are built up and how they work - also materials that we need to become less dependent on fossil fuels, for example materials in solar cells, in batteries and in the production of green hydrogen. What influences the climate and how can we counteract climate change and cope with the consequences? Society must deal with these three central problems of climate change (physical science basis, mitigation, adaptation according to the IPCC), and research with synchrotron radiation makes a valuable contribution to this. Important research fields are e.g. Photovoltaics, Batteries, Catalysis, Hydrogen storage and Understanding climate change. More information can be found at idw and the SNI-portal. The KFS is an elected representative of the more than 4000 users of synchrotron radiation sources in Germany and at international institutions with German participation.

KIT

By the combination of several methods it was possible for the first time to investigate the water splitting reaction at high overpotentials despite the strong bubble evolution. By analyzing PCA of XAS spectra of uncalcined IrO2 during the oxygen evolution reaction, we identified components that can be attributed to two reaction modes, the Absorbate Evolution Mechanism and the Lattice Oxygen Mechanism. Furthermore, we observed partially irreversible formation of metal like Ir-Ir distances of surface layers by removal of oxygen as terminal side reaction under cycling to high potentials (≥1.55V).

https://pubs.acs.org/doi/abs/10.1021/acscatal.1c02074

The catalytic hydrogenation of CO2 is a promising way to store large amounts of renewable energy while reducing CO2 emissions (P2X concept). Marc-André Serrer (IKFT), Matthias Stehle (ITCP) and further colleagues at IKFT, ITCP and IAM-AWP uncovered the reaction progress along a conventional Ni-based and an advanced Ni-Fe-based catalyst during CO2 methanation in a fixed-bed reactor. By using a dedicated new setup, they were able to reveal changes in activity, selectivity, and temperature along the catalyst bed. Complementary spatially resolved structural investigations by X-ray absorption spectroscopy showed that the oxidation state of Fe is strongly influenced by the increasing amount of water towards the end of the catalyst bed. Furthermore, infrared spectroscopy unraveled that Fe species promote the higher activity of the bimetallic catalyst by protecting active Ni0 centers from strongly adsorbed CO. Hence, this example underlines not only the importance to consider gradients in chemical reactors but that they even can be exploited for better understanding.

Just now the Collaborative Research Centre 1441 TrackAct (Tracking the Active Site in Heterogeneous Catalysis for Emission Control) at Karlsruhe Institute of Technology (KIT) has started. Catalysis is at the core of the initiative that is conducted together with partners in Munich and the synchrotron radiation source in Hamburg. Within this program, we thus seek for PhD candidates in various fields from Chemistry, Chemical Engineering, Material Sciences to Physics, for more information see here: www.trackact.kit.edu/159.php

Johannes Becher

Chemical gradients in automotive Cu-SSZ-13 catalysts for NOx removal revealed by operando X-ray spectrotomography

Gradients in the copper oxidation state and coordination environment of Cu-SSZ-13 catalyst were observed using XANES tomography. For this purpose, a newly developed setup was used that allows XANES tomography to be performed under realistic (operando) conditions. The interplay of adsorption-desorption processes and mass transfer effects was analysed with micrometre resolution in 3D.

Florian Maurer

Tracking the formation, fate and consequence for catalytic activity of Pt single sites on ceria

The location of platinum single sites on ceria and the variation of the active state were investigated in an operando approach while combining different methods like in situ infrared spectroscopy, operando high-energy-resolution fluorescence detected X-ray absorption spectroscopy, catalytic CO oxidation and density functional theory calculations.

SFedU

On October 7th, the groups of Prof. Dr. Grunwaldt (KIT, Karlsruhe, DE) and Prof. Dr. Soldatov (SFedU, Rostov-on-Don, RU) held a joint virtual workshop on Hard X-ray Spectroscopy and Advanced Data Analysis for Catalysis. The workshop brought together over 50 scholars from Germany – Karlsruhe Institute of Technology, and Russia – The Smart Materials Research Institute at the Southern Federal University. The talks were devoted to the infrastructure and experimental research highlights from KIT as well as the advances of SFedU in the areas of machine learning, big data analysis and prediction of X-ray absorption spectra for catalytically active materials.

AKGrunwaldt

The AK Grunwaldt has started on February 1, 2010, in Karlsruhe!

10 years Karlsruhe in 2020! Unfortunately, an "on-site" celebration is currently not possible, but an online meeting is planned.

Daria Gashnikova

Daria Gashnikova has received a scholarship for her PhD work. Congratulations! She will work in the currently highly relevant field of emission control of stoichiometrically operated natural gas engines with a focus on the removal of NOx. Good luck!

The lectures could be performed succesfully online during the summer semester 2020. The courses in the upcomming winter semester will probably be also online. The following courses will take place in the next semester: Chemische Technik: Katalyse, Aktuelle Konzepte in der Heterogenen Katalyse as well as lectures to synchrotron methods, emission control as well as chemical energy storage/energy transition. More information on the homepage of the institute.

E.Saraci, M. Serrer, J.-D. Grunwaldt

Showcasing research from Professor Grunwaldt and colleagues at the ITCP, IKFT and IMVT at KIT:

Bridging the gap between industry and synchrotron: an operando study at 30 bar over 300 h during Fischer–Tropsch synthesis.

We design new infrastructure for operando high-pressure synchrotron experiments. High structural stability of a Fischer-Tropsch catalyst was found during a long-term study under industrial conditions while producing synthetic fuels.

Dr. Thomas Sheppard from ITCP was officially recognised as leader of a new KIT Young Investigator Group – X-ray Microscopy in Catalysis (2020-2022).

J. Synchrotron Radiation

On the cover of Journal of Synchrotron Radiation - scientists from DESY (Hamburg) and ITCP-KIT demonstrate a deep learning algorithm for X-ray tomography reconstruction, which is particularly useful for in situ and operando sample environments.

Xiaogang Yang, Maik Kahnt, Dennis Brückner, Andreas Schropp, Yakub Fam, Johannes Becher, Jan-Dierk Grunwaldt, Thomas L. Sheppard, Christian G. Schroer, Journal of Synchrotron Radiation 2020.

SPP2080

The Kick-Off-Meeting of the DFG priority program SPP2080 "Catlysts and reactors under dynamic conditions for energy storage and conversion" was held at KIT. Here you can find KIT's official press information.

XRM of model catalyst highlight

A recent publication on X-ray nanotomography of a model catalyst material was announced as a research highlight by the ‘Paul Scherrer Institut’ (Switzerland), where the work was carried out. For further info check out the link.

Y. Fam, T. L. Sheppard, A. Diaz, T. Scherer, M. Holler, W. Wang, D. Wang, P. Brenner, A. Wittstock, J.-D. Grunwaldt, ChemCatChem 2018, 10, 2858 –2867

Novel gold- and silver-based catalysts have been used for the synthesis of potential monomers for sustainable plastics via oxidation of 5-(hydroxymethyl)furfural, an important platform molecule produced from biomass. The catalysts showed distinct selectivities in the oxidation of different functional groups, which made the targeted synthesis of interesting monomers possible.

O. R. Schade, K. F. Kalz, D. Neukum, W. Kleist, J.-D. Grunwaldt, Green Chem., 2018, DOI: 10.1039/C8GC01340C

Research work from ITCP, IKFT, and IMVT was highlighted in Chemical & Engineering News. By looking at a palladium catalyst while it converts hydrogen and oxygen to hydrogen peroxide, researchers have uncovered that α-palladium hydride nanoparticles were responsible for the selective hydrogenation of oxygen to hydrogen peroxide. “This is a very interesting study as it probes the nature of a palladium catalyst under operating conditions and clearly shows the potential role of various palladium hydrides in this challenging reaction,” says Graham J. Hutchings from Cardiff University.

Selinsek, M.; Deschner, B. J.; Doronkin, D. E.; Sheppard, T. L.; Grunwaldt, J.-D.; Dittmeyer, R. ACS Catal. 2018, 8, 2546-2557

PD Dr. Wolfgang Kleist has been appointed Professor for Technical Chemistry at the Ruhr University Bochum. Congratulations!

Johannes Bitzer, Deniz Zengel and Florian Maurer have received scholarships for their PhD works. Congratulations!

Do not hesitate to write us if you are interested in catalysis, biomass conversion, spectroscopy, or solid state chemistry.