Lieu

Moyen amphi (LPS
Bât 510, Orsay (91)

Date

20 Mai 2022

Heure

11h00 - 0h00

Guillermo Gonzales Rubio – Seed-mediated Growth, Analytical Ultracentrifugation, and Femtosecond Laser Irradiation for Controlled Colloidal Gold Nanorod Fabrication.

University of Konstanz (Germany), Physical Chemistry

Gold is probably one of the most researched materials in nanoscience and nanotechnology for diverse cancer diagnosis and treatment applications, water remediation, or photocatalytic carbon dioxide recycling. Such an interest withdrawn by gold nanoparticles can be explained by their ability to interact strongly with light in a manner tightly dependent on the morphology and size of the nanocrystal. In particular, when gold adopts the shape of a rod, and the length-to-width ratio is varied, colloids with tunable narrow extinction bands in the visible and near-infrared regions can be obtained. The development of synthesis and post-synthesis modification methods to tailor gold nanorod anisotropy is thus crucial to producing gold colloids with desired optical properties and eventually facilitating their practical implementation in technology.

This talk will discuss different routes to produce gold nanorod colloids based on surfactant-assisted seed-mediated growth approaches and femtosecond laser irradiation. The phenomena of symmetry breaking, anisotropic and chiral growth, and laser-induced reshaping of gold nanocrystals will be discussed, including how the complex interplay between various experimental parameters determines the quality of the resulting gold nanorod colloid. In this context, I will show recent advances made toward the in-situ characterization of colloidal nanoparticles using the analytical ultracentrifugation technique. I will show the importance of analytical ultracentrifugation experiment design to obtain information fundamental to unveiling nanorod growth mechanisms and developing optimal synthesis methods.

References

  • G. González-Rubio et al. Femtosecond laser reshaping yields gold nanorods with ultranarrow surface plasmon resonances. Science. 2017, 358, 640–644.
  • G. González-Rubio et al. Disconnecting Symmetry Breaking from Seeded Growth for the Reproducible Synthesis of High Quality Gold Nanorods. ACS Nano. 13, 2019, 4424–4435.
  • G. González-Rubio et al. Micelle-directed chiral seeded growth on anisotropic gold nanocrystals. Science. 368, 2020, 1472–1477.
  • G. González-Rubio et al. Surfactant-Assisted Symmetry Breaking in Colloidal Gold Nanocrystal Growth. ChemNanoMat. 2020, 6, 698–707.
  • G. González-Rubio et al. Simple Determination of Gold Nanocrystal Dimensions by Analytical Ultracentrifugation via Surface Ligand-Solvent Density Matching. Nanomaterials. 2021, 11, 1427.