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Ultra-Fine Control of Silica Shell Thickness on Silver Nanoparticle-Assembled Structures.

ABSTRACT: To study the distance-dependent electromagnetic field effects related to the enhancement and quenching mechanism of surface-enhanced Raman scattering (SERS) or fluorescence, it is essential to precisely control the distance from the surface of the metal nanoparticle (NP) to the target molecule by using a dielectric layer (e.g., SiO₂, TiO₂, and Al₂O₃). However, precisely controlling the thickness of this dielectric layer is challenging. Herein, we present a facile approach to control the thickness of the silica shell on silver nanoparticle-assembled silica nanocomposites, SiO₂@Ag NPs, by controlling the number of reacting SiO₂@Ag NPs and the silica precursor. Uniform silica shells with thicknesses in the range 5-40 nm were successfully fabricated. The proposed method for creating a homogeneous, precise, and fine silica coating on nanocomposites can potentially contribute to a comprehensive understanding of the distance-dependent electromagnetic field effects and optical properties of metal NPs.

SUBMITTER: Hahm E

PROVIDER: S-EPMC8584519 | biostudies-literature |

REPOSITORIES: biostudies-literature

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