Optical absorption analysis of core-shell type Ni@Ag/Au & NiFe@Ag/Au magneto-plasmonic nanostructures

The core-shell nanoparticles are greatly advocated for their usefulness in biomedical applications tending to targeted drug delivery, sensing, and bio-imaging. In this paper, the optical properties of simple; Ni@Ag/Au and complex; NiFe@Ag/Au magnetoplasmonic nanoparticles for their core-shell structures with spherical and prolate geometries are comprehensively investigated using the discrete dipole approximation (DDA) method. It is found that the Localized Surface Plasmon Resonance (LSPR) for absorption (lambda(max)) as well as efficiency (intensity) strongly depend on the geometry of the nanoparticle, aspect ratio, core sizes, and shell thickness. The absorption spectra which are generally found in the 335-717 nm wavelength ranges can be tuned in the ultra violet-near-infrared (UV-NIR) region of the electromagnetic (EM) spectrum for desired biomedical applications. It is discovered that there is a higher tunability of LSPR peak position as well as larger enhancement in the absorption efficiency when the spherical nanoparticle stretches to prolate core-shell configuration. Based on these findings, therefore, it is suggested that the proposed core-shell nanostructures with the tunable optical response in the visible region have potentials in cancer therapy, drug delivery, and optical imaging. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

The study found that the localized surface plasmon resonance (LSPR) for absorption and efficiency strongly rely on the geometry, aspect ratio, core sizes, and shell thickness of the nanoparticle. The absorption spectra generally fall within the 335-717 nm wavelength ranges and can be adjusted for desired biomedical applications in the UV-NIR region of the electromagnetic spectrum.