Additive-Free Synthesis of (Chiral) Gold Bipyramids from Pentatwinned Nanorods
The production of colloidal metal nanostructures with complex geometries usually involves shape-directing additives, such as metal ions or thiols, which stabilize high-index facets. These additives may however affect the nanoparticles' surface chemistry, hindering applications, e.g., in biology or catalysis. We report herein the preparation of gold bipyramids with no need for additives and shape yields up to 99%, using pentatwinned Au nanorods as seeds and cetyltrimethylammonium chloride as surfactant. For high-growth solution:seed ratios, the bipyramids exhibit an unusual "belted" structure. Three-dimensional electron microscopy revealed the presence of high-index {117}, {115}, and {113} side facets, with {113} and {112} facets at the belt. Belted bipyramids exhibit strong near-field enhancement and high extinction in the near-infrared, in agreement with electromagnetic simulations. These Ag-free bipyramids were used to seed chiral overgrowth using 1,1'-binaphthyl-2,2'-diamine as a chiral inducer, with <i>g</i>-factor up to 0.02, likely the highest reported for bipyramid seeds so far.
Authors
- Sara Bals (ORCID: https://orcid.org/0000-0002-4249-8017)
- J. M. Taboada (ORCID: https://orcid.org/0000-0003-1660-8910)
- Kyle Van Gordon
- Francisco Bevilacqua (ORCID: https://orcid.org/0009-0008-3426-8271)
- Johan Hofkens (ORCID: https://orcid.org/0000-0002-9101-0567)
- Manuel Obelleiro‐Liz (ORCID: https://orcid.org/0000-0003-3038-8360)
- Victor F. Martín (ORCID: https://orcid.org/0000-0001-7095-7148)
- Robin Girod (ORCID: https://orcid.org/0000-0001-7861-7818)
- Luis M. Liz‐Marzán (ORCID: https://orcid.org/0000-0002-6647-1353)
- Gail A. Vinnacombe‐Willson (ORCID: https://orcid.org/0000-0002-6897-6574)
Institutions
- Ikerbasque (ES)
- University of Antwerp (BE)
- CIC biomaGUNE (ES)
- Boeing (Spain) (ES)
- Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine (ES)
- Centro de Investigación Biomédica en Red (ES)
- ResearchWorks (United States) (US)
- Universidad de Los Andes (BO)
- Digital Research Alliance of Canada
- Universidade de Vigo (ES)
- Universidad de Extremadura (ES)
- KU Leuven (BE)
Publication Details
- Journal
- ACS Materials Letters
- Published
- 2024-10-17
- DOI
- https://doi.org/10.1021/acsmaterialslett.4c01605
- Citations
- 11
- Primary Topic
- Gold and Silver Nanoparticles Synthesis and Applications
- Type
- article
- Field-Weighted Citation Impact
- 1.30
Funders
- Ministerio de Ciencia, Innovación y Universidades
- KU Leuven
- Onderzoeksraad, KU Leuven
- Agencia Estatal de Investigación
- H2020 European Research Council