FDTD modeling of sputtered Mo–Al2O3 nanocomposites

Abstract

Ceramic-metal nanocomposites (NCs) are the one of the most promising materials for selective solar absorbers (SSAs) in renewable energy applications. Design of efficient SSAs demands precise modeling of light propagation in NCs. We report on the synthesis, detailed characterization, and analytical and numerical modeling of Molybdenum (Mo)-alumina (Al2O3) NCs. In this study, Mo–Al2O3 NC films with thicknesses of 45 nm and 60 nm and nominal metal volume fraction (f) of 30%, 40%, and 60% were grown on polished glass substrates, using sequential DC and RF sputtering. TEM analysis of the samples with f = 40% showed that most 2 nm-diameter Mo particles are spherical and isolated. The reflectance (R) and transmittance (T) curves of the NC were measured in the spectral range of 300 nm and 1700 nm. The measured R and T characteristics were compared with the calculated FDTD simulations to analyze the prediction accuracy of the approach.