Speaker
Description
Nanomaterials with well-controllable structure are of particular interest in many fields of research, and knowledge on their formation mechanism and structural evolution is essential for developing precise chemical synthesis routes. Complementing the capabilities of liquid-cell transmission electron microscopy (TEM), we can use X-ray ptychography, a scanning coherent diffraction imaging (CXDI) technique, to record micrographs inside an extended and heated chemical reactor. This can enable us to follow the evolution of size and morphology of nanoparticles in a solution-based synthesis in real time. With state-of-the-art nanofocused synchrotron beams, a spatial resolution of a few tens of nanometers can be achieved even when imaging weakly scattering objects in an extended liquid environment [1,2].
I will briefly introduce the Ptychographic Nanoanalytical Microscope (PtyNAMi) [3] at the nanofocus endstation of beamline P06 at PETRA III, and present a sample environment for running chemical syntheses in the X-ray beam, featuring a heatable pressure cell with nanoscale position stability. This setup enables long-term observations of chemical processes.
We synthesize cuprous oxide nanocubes in a solvothermal approach from a metal-organic precursor, that exhibit a dynamic morphological evolution at later reaction stages, when a solid-state reduction to the metallic state takes place [4]. This nanomaterial with sizes in the range of a few hundreds of nanometers is well suited to demonstrate the advantages of our X-ray microscopy approach. Such rare visual insights into structural changes in solution are important to deepen our understanding of the origins of nanomaterial morphology.
References
[1] M. Kahnt et al. Scientific Reports 11, 1500 (2021)
[2] J. Reinhardt et al., Ultramicroscopy 173, 52 (2017)
[3] A. Schropp et al., J. Appl. Cryst. 53, 957-971 (2020)
[4] N. Kränzlin et al. Adv. Mater. Interfaces 2, 1500094 (2015)
| Speaker Country | Germany |
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