Atomic-Scale Imaging of Transformation of Nickel Nanocrystals to Nickel Carbides in Real Time.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 40512101.
- Also identified by DOI 10.1021/acsnano.5c06292 and PMC identifier 12224334.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Transition of metal-to-metal carbide plays a key role in heterogeneous catalysis. We confined nickel nanocrystals in single-walled carbon nanotubes, stimulated delivery of carbon atoms by the 80 keV electron beam, and imaged the entire carbonization process by time-resolved aberration-corrected transmission electron microscopy at the atomic scale. Metal nanocrystal Ni<sub>40</sub> progressively capturing carbon atoms evolved from pure metal to Ni<sub>40</sub>C<sub>20</sub> and then to Ni<sub>40</sub>C<sub>40</sub>. The carbonization is accompanied by changes in the structure of the crystal, including a two-dimensionalization process, at the Ni<sub>40</sub>C<sub>40</sub> stage. This work provides valuable insights into the atomic mechanism of metal carbide formation, which may help to develop stable catalysts and provide a reliable route for synthesizing metal-based two-dimensional materials.