A research team at Seoul National University has developed a method based on in-situ Brownian tomography to analyze three-dimensional atomic structure changes in nanoparticles. By using transmission electron microscopy (TEM) to capture images of nanoparticles moving within a liquid between graphene layers, they were able to reconstruct three-dimensional images over time. (Image provided by Seoul National University)
The team succeeded in directly tracking the process of atomic-level structural changes in single nanoparticles over time using the newly developed "in-situ Brownian tomography." This achievement is expected to open the way to a deeper understanding of atomic-level structural changes in nanoparticles where complex chemical reactions occur.
In liquid environments, the researchers observed nanoparticles moving freely in random directions and reconstructed their movements into 3D structures over time. They captured, for example, the exact moments when platinum (Pt) nanoparticles detached from or reattached to the nanoparticle surface during partial dissolution processes.
The team also found that when platinum nanocrystals shrink to about 1 nanometer in size, they display highly irregular atomic arrangements. Unlike typical platinum structures with highly ordered atomic arrangements, these ultra-small nanoparticles can exhibit unique structures due to their extremely limited number of constituent atoms.
The newly developed in-situ Brownian tomography is considered an innovative technology that can analyze time-dependent 3D structural changes in nanomaterials, and it is expected to make a significant contribution to the future development of high-performance catalysts.
Professor Park explained, “This technology will contribute greatly to clarifying the complex reaction mechanisms occurring in various energy materials, including hydrogen fuel cells, lithium-ion batteries, and catalysts, and to designing more efficient and advanced materials.”
[Reference]
doi.org/10.1038/s41467-025-56476-8
([2/25] News release: Dong-A Science, “Directly observing the three-dimensional atomic structural changes of nanoparticles in real time”)