Fine-tuning of localized surface plasmon resonances in gold nanoshells

Abstract

High-qualitysilica core and gold shell spherical nanoparticles were synthesized withprecise control over their dimensions and well-defined plasmonic resonances. Wedemonstrate that the simultaneous synthesis and adsorption of small gold seedsonto functionalized SiO2 spheres, combined with a suitable reducingagent and optimized reaction conditions, are crucial for the growth andcoalescence of the gold seeds into uniform and closed layers. This improvementenables the production of core-shell nanostructures whose extinction spectraexhibit excellent agreement with predictions from Mie theory.