Halide-assisted differential growth of chiral nanoparticles with threefold rotational symmetry
Enriching the library of chiral plasmonic nanoparticles that can be chemically mass-produced will greatly facilitate the applications of chiral plasmonics in areas ranging from constructing optical metamaterials to sensing chiral molecules and activating immune cells. Here we report on a halide-assisted differential growth strategy that can direct the anisotropic growth of chiral Au nanoparticles with tunable sizes and diverse morphologies. Anisotropic Au nanodisks are employed as seeds to yield triskelion-shaped chiral nanoparticles with threefold rotational symmetry and high dissymmetry factors. The averaged scattering g-factors of the l- and d-nanotriskelions are as large as 0.57 and − 0.49 at 650 nm, respectively. The Au nanotriskelions have been applied in chiral optical switching devices and chiral nanoemitters. We also demonstrate that the manipulation of the directional growth rate enables the generation of a variety of chiral morphologies in the presence of homochiral ligands.
Acknowledgements: C.B. is thankful for funding from the Engineering and Physical Sciences Research Council (EPSRC, Standard Research Studentship (DTP) EP/R513180/1). G.R.L. is thankful for funding from the EPSRC NanoDTC Cambridge (EP/L015978/1). L.S. acknowledges support from the Pearl River Talent Recruitment Program (2019QN01C216). J.W. acknowledges support from the Croucher Foundation (Croucher Senior Research Fellowship 2020-2021), the Hong Kong Government (Research Matching Grant Scheme, Project Code 8601434), and the Research Grants Council of Hong Kong (ANR/RGC, A-CUHK404/21). This project received support from Shenzhen Science and Technology Program (JCYJ20210324140805014) and the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement No. 804523).
Funder: Pearl River Talent Recruitment Program, 2019QN01C216
Croucher Foundation (Croucher Senior Research Fellowship 2020-2021)
Research Grants Council, University Grants Committee (RGC, UGC) (A-CUHK404/21)
Shenzhen Science and Technology Innovation Commission (JCYJ20210324140805014)
EC | EU Framework Programme for Research and Innovation H2020 | H2020 Priority Excellent Science | H2020 European Research Council (H2020 Excellent Science - European Research Council) (804523)