Effect of component volume ratio on the absorption spectra of Ag@Fe3O4 core–shell nanoparticles

Abstract

In this paper, we study the absorption efficiency spectra and electric field distribution of Ag nanoparticles enveloped with [Formula: see text] nanoshell by applying the discrete dipole approximation theory. Three kinds of [Formula: see text] core–shell nanoparticles (NPs) structural variables, including the same core with different shell thickness, the same outer shell with different core radius, and the same size of total radius have been discussed in detail. The simulated results show that the localized surface plasmon resonance (LSPR) peak wavelength of NPs is linearly proportional with the volume fraction of the shell, regardless of the outer shell material property and one structural variable. Compared to the plasmon resonance peak of the Ag nanoparticles, the LSPR shift of the NPs is dependent on both the total particles size and the outer [Formula: see text] shell thickness. The electric field around the surface of NPs becomes weaker under the same damping when the core radius decreases. Based on the plasmonic characteristics revealed in this study, it is suggested that it would provide some key guidances for designing the future NPs structural variables for a broad range of plasmon applications.