INT | Research Group Kübel

Materials Research

The aim of our research is to correlate synthesis and processing of materials with properties and device function through their atomic, nano and micro scale structure in order to provide a knowledge base for tailoring new materials.

We are using state-of-the-art imaging, spectroscopy and diffraction based electron microscopy techniques, both in-situ and ex-situ, to understand materials and provide a link to simulations. When state-of-the-art techniques do not provide sufficient answers, we tackle research problems by dedicated method developments.

Structure-Property Relationships Christian Kübel, KIT

Method Development

While state-of-the-art electron microscopy techniques are extremely powerful, some research problems require dedicated method development to answer challenging structural or functional questions.

We are focusing on three main methdology areas in repsonse to the needs of our collaborations partners, developing approaches for dedicated structural and functional analysis of materials at the atomic or nanoscale.

In-situ TEM

In-situ and operando TEM provides a direct link between structural evolution and materials properties or function and the ability to identify transient structures, which cannot be observed ex-situ. We are using and optimizing the techniques, combining them in particular with various 4D-STEM and spectroscopic techniques.

  • Mechanical testing
  • Heating
  • Cooling
  • Biasing
  • Electrochemistry
  • Gas environment
In-situ TEM Atmosphere Holder Protochips Inc.
In-situ TEM

Heating, biasing, electro-chemistry, gas environment, mechanical deformation

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4D-STEM

4D-STEM techniques have been shown to be extremely powerful, opening the possibility of high-end structural characterization using ptychography, pair distribution function mapping or quantitative crystal orientation analysis as well as functional characterization by quantitatively measuring magnetic or electric field distributions.

  • ACOM-STEM: Crystal orientation mapping
  • STEM-PDF: Atomic pair distribution function mapping for local atomic bonding and coordination in disordered and amorphous materials
  • STEM-DPC and STEM-iDPC: Differential phase contrast imaging for local mean potential and magnetic field imaging
4D-STEM Xiaoke Mu, KIT
4D-STEM

Automated crystal orientaton mapping

Pair distrubution function mapping

Differential phase contrast

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Electron Tomography

We are developing electron tomography as an approach to quantify the 3D nano and micro structure. In collaborations, we are using this experimental 3D structure as basis for diffusion or flow simulations.

  • STEM tomography
  • EDX tomography
  • FIB Slice & View
  • Quantitative tomography analysis
Electron Tomography in Catalysis Wu Wang, KIT
Electron Tomography

Quantitative 3D nanoscale and microscale analysis

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Supporting Developments