| Publications of Laboratory "Matériaux et Phénomènes Quantiques" (UMR 7162) |  |
Journal articles
Quantitative in situ visualization of thermal effects on the formation of gold nanocrystals in solution
Abstract : Understanding temperature effects in nanochemistry requires real-time in situ measurements because this key parameter of wet-chemical synthesis simultaneously influences the kinetics of chemical reactions and the thermodynamic equilibrium of nanomaterials in solution. Here, temperature-controlled liquid cell transmission electron microscopy is exploited to directly image the radiolysis-driven formation of gold nanoparticles between 25 °C and 85 °C and provide a deeper understanding of the atomic-scale processes determining the size and shape of gold colloids. By quantitatively comparing the nucleation and growth rates of colloidal assemblies with classical models for nanocrystal formation, it is shown that the increase of the molecular diffusion and the solubility of gold governs the drastic changes in the formation dynamics of nanostructures in solution with temperature. In contraction with the common view of coarsening processes in solution, it is also demonstrated that the dissolution of nanoparticles and thus the Ostwald ripening is not only driven by size effects. Furthermore, visualizing thermal effects on faceting processes at the single nanoparticle level reveals how the competition between the growth speed and the surface diffusion dictates the final shape of nanocrystals.
https://hal.archives-ouvertes.fr/hal-03414114
Contributor : Laurine Wibaux Connect in order to contact the contributor
Submitted on : Thursday, November 4, 2021 - 11:02:33 AM
Last modification on : Thursday, April 7, 2022 - 1:58:33 PM
Long-term archiving on: : Saturday, February 5, 2022 - 6:30:51 PM
Contributor : Laurine Wibaux Connect in order to contact the contributor
Submitted on : Thursday, November 4, 2021 - 11:02:33 AM
Last modification on : Thursday, April 7, 2022 - 1:58:33 PM
Long-term archiving on: : Saturday, February 5, 2022 - 6:30:51 PM
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DMAS21081_vacceptee.pdf
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