Colloidal Gold Nanostructures for Plasmonics

Our research activities concentrate on the synthesis and assembly of gold nanoparticles (NPs) with tunable sizes and shapes, to provide original materials for research in plasmonics through collaborations (1,2,3,4). ... [ view full abstract ]

Our research activities concentrate on the synthesis and assembly of gold nanoparticles (NPs) with tunable sizes and shapes, to provide original materials for research in plasmonics through collaborations (1,2,3,4).
We synthesize non-commercial Au-NPs: nanospheres (perfectly spherical and very large), nanocubes, prisms, nanooctahedra and micro-plates of various size and thicknesses. Perfect spheres and cubes on top of Au-film are very attractive for spectroscopies within the gap; Prisms are promising for ultrasensitive sensing; Plates can spontaneously self-assemble in ordered 1D-columnar aggregates (fig) or 2D-metasurfaces; their large atomically flat facets are promising for F.I.B. fabrication of monocrystalline structures.
Assembly of such NPs leads to the appearance of new properties, still relatively poorly explored, apart from SERS experiments. Here, we report the spontaneous self-assembly of gold NPs by simply evaporating concentrated solutions on non-patterned substrates. The degree of reproducibility of this method, the maximum size of the perfectly organized area and the key parameters related to a controlled-deposition are presented We are looking for collaborations to study the optical properties of these unusual assemblies and the plasmon-driven chemical reactions that should occur as a result of strong light-matter interation within the hot-spots.
References:
(1) C. Molinaro et al, soumis J.Phys.Chem.C
(2) E. Le Moal et al. Phys.Rev.B-2016 ; Nano-Lett-2013
(3) M. Haggui et al. ACSnano-2012
(4) C. Deeb et al. J. Phys. Chem. C-2012