Controlling the Topography and Surface Plasmon Resonance of Gold Nanoshells by a Templated Surfactant-Assisted Seed Growth Method

Abstract

Gold nanoshells with varying surface topographies and tunable SPR bands were synthesized in high yields by the templated surfactant-assisted seed growth method. By changing the types and amounts of surfactants and ionic additives in the growth solution, the nanoshell topography was controlled from smooth shells to highly structured nanoshells composed of spherical nanoparticles or sharp spikes of varying aspect ratios. The SPR band of the nanoshells could be tuned over a wide range of wavelengths by varying the nanoshell topography, without significantly changing the amount of gold. Finite-difference time-domain (FDTD) modeling was used to predict and understand the optical properties of nanoshells composed of various subparticles, providing insight into the origins of the tunable SPR band.