Online-Seminare

Online-Seminare der Fachgruppe Festkörperchemie & Materialforschung

Die Fachgruppe Festkörperchemie & Materialforschung startete im Jahr 2021 eine Online-Vortragsreihe zur Förderung des wissenschaftlichen Austauschs auch über die derzeitige Corona-Pandemie hinaus durch ortsunabhängige, zweiwöchentliche Vorträge. Die Teilnahme ist kostenlos. Eine separate Registrierung für jedes Seminar ist erforderlich (Details siehe unten).

Organisation:
Dr. Sebastian Klemenz, Dr. Simon Steinberg, Dr. Christopher Benndorf,
Dr. Alexander Knebel, Jun.-Prof. Dr. Nathalie Kunkel
 

Online Seminar #1: Harun Tüysüz

PD Dr. Harun Tüysüz (MPI für Kohlenforschung)
March 2, 2021
6:00-7:30pm (Berlin time)

The seminar is free of charge, but REGISTRATION with Zoom (zoom.us) is needed!

“Tailor-made Nanostructured Materials for Energy Conversion Applications”
My particular research interest is the design of well-defined nanostructured materials and studying their structure-activity relationships for sustainable energy-related catalytic applications. The focus of the first part of the lecture will be design and development of Co, Ni and Fe based electrocatalysts for oxygen evaluation reactions. This will be followed by the presentation of solid-state inorganic halide perovskites and their implementation as functional photocatalysts for prototype reactions.

Online Seminar #2: Oliver Clemens

Prof. Dr. Oliver Clemens (Universität Stuttgart)
NEW DATE: Mach 23, 2021
6:00-7:30pm (Berlin time)

The seminar is free of charge, but REGISTRATION with Zoom (zoom.us) is needed!

“Anion Chemistry of Energy Materials – Batteries, Tunable Properties, and Electrocatalysts”
Without doubt, topochemical reactions play an important role for our current batteries, e.g., within oxide-based cathode materials or carbon-based anode materials for lithium-ion batteries. However, topochemistry of oxide materials is by no means restricted to small cations, and perovskite as well as perovskite-related materials possess a vivid insertion chemistry for anions, making them interesting compounds for a broad range applications related to their multitude of functional properties, among them magnetism and superconductivity. In this talk, the use of topochemical reactions with anions to develop and understand new energy materials with tailored and tunable properties will be highlighted. These reactions cover the preparation of oxyfluorides and oxyhydroxides for fluoride-ion batteries and electrocatalytic (SOFC and PCFC) applications. Special focus will be set on using topochemistry for the reversible on/off-switching of material properties. Last but not least, the impact of anion and vacancy ordering on the intrinsic properties will be given, with a special focus on barium ferrates and cobaltates with perovskite-related structure, for which novel compounds could be prepared and structurally characterized.

Online Seminar #3: Sebastian Henke

Jun.-Prof. Dr. Sebastian Henke (TU Dortmund)
Mach 30, 2021
6:00-7:30pm (Berlin time)

The seminar is free of charge, but REGISTRATION with Zoom (zoom.us) is needed!

„Stimuli-Responsiveness, Melting and Glass Formation of Metal-Organic Frameworks “
Metal-organic frameworks (MOFs) are an emerging family of porous solid-state materials exhibiting huge potential for various technological applications (gas storage/separation, catalysis, drug delivery, sensing, etc.). These compounds are composed of inorganic building units (typically d-block metal ions, metal-(oxo/hydroxo)-clusters) which are interconnected by multidentate organic linkers to generate two- or three-dimensional extended networks, exhibiting huge internal surface areas and pore volumes. In this talk, I present our recent efforts in different areas of MOF chemistry. Firstly, I introduce flexible MOFs, which undergo dramatic structural changes as a function of guest molecule adsorption/desorption, temperature or mechanical pressure. By chemical modification or exchange of the frameworks’ building units, the structural response of the MOF can be tunes systematically. Secondly, I demonstrate the preparation of liquid MOFs and their corresponding glasses. MOF glasses represent a new class of glassy materials and own intrinsic porosity, similar to their crystalline parent compounds. We revealed that MOF glasses are able to adsorb even relatively large hydrocarbon gas molecules, thus enabling kinetic gas separation (i.e. the separation of propylene from propane). Finally, I present a new concept for the design of porous framework materials that can be processed (i.e. drop casted, crystallized, etc.) from aqueous solution. Our materials design strategy is based on amphiphilic organic building blocks which reversibly assemble/disassemble to micellar porous frameworks, mediated by coordination to alkali ions in aqueous solution.

Online Seminar #4: Janine George

Dr. Janine George (Université catholique de Louvain)
April 13, 2021
6:00-7:30pm (Berlin time)

The seminar is free of charge, but REGISTRATION with Zoom (zoom.us) is needed!

„Data-driven materials discovery and chemical understanding“
Developments in density functional theory (DFT) calculations, their automation and easy access to materials data have enabled ab initio high-throughput searches for new materials for numerous applications. These studies open up exciting opportunities to find new materials in a much faster way than based on experimental work alone. However, performing density functional theory calculations for several thousand materials can still be very time consuming. The use of, for example, faster chemical heuristics and machine-learned interatomic potentials would allow to consider a much larger number of candidate materials. In addition to DFT based high-throughput searches, the seminar will discuss two possible ways to accelerate high-throughput searches. Using data analysis on the structures and coordination environments of 5000 oxides, we were able to investigate a chemical heuristic – the famous Pauling rules – regarding its usefulness for the fast prediction of stable materials. We have also investigated how machine-learned interatomic potentials can be used to accelerate the prediction of (dynamically) stable materials. The use of these potentials makes vibrational properties accessible in a much faster way than based on DFT. Our results based on a newly developed potential for silicon allotropes showed excellent agreement with DFT reference data (agreement of the frequencies within 0.1-0.2 THz). In addition, we have successfully used high-throughput calculations in the search for new candidate materials for spintronic applications and ferroelectrics.

zuletzt geändert am: 08.02.2021 18:21 Uhr von C.Kniep