Scattering and absorption of light by homogeneous BiFeO3 and hybrid BiFeO3/Au core/shell spherical nanoparticles: A computational study

Abstract

The scattering and absorption properties of light by a single spherical nanoparticle embedded in a non-absorbing, isotropic and homogeneous medium are analyzed theoretically in the framework of Lorenz-Mie theory. We consider separately the case of a homogeneous BiFeO3 nanoparticle, and the case of a hybrid BiFeO3/Au core/shell nanoparticle. We address the influence of particle-diameter and gold-shell thickness on the scattering and absorption efficiencies of such nanostructures. In addition, we discuss the effectiveness of these nanoparticles in some applications based on scattering and/or absorption of light. The ability of BiFeO3 nanoparticles to absorb visible light, combined with their photovoltaic properties, makes them effective photocatalysts under visible light irradiation. The intense absorption resonances of light by BiFeO3/Au nanoshells within the NIR biological windows of a human tissue make these nanoplasmonics promising agents for photothermal therapy. On the other hand, the BiFeO3/Au nanoshells effectively backscatter NIR radiations centred at wavelengths of 830 and 1310nm, and hence are good contrast agents for optical coherence tomography of human tissue.