In silico design of metal-dielectric nanocomposites for solar energy applications

TL;DR

This paper presents a computational method to design metal-dielectric nanocomposites with optimized optical absorption for solar energy applications, demonstrating significant broadband enhancement through simulation and optimization techniques.

Contribution

It extends a homogenization approach to quaternary nanocomposites and introduces a simulated annealing method to optimize their composition for solar energy harvesting.

Findings

Enhanced broadband absorption (350-800 nm) achieved in nanocomposites.

Absorption can be tuned by adjusting nanosphere size and metal volume fractions.

Optimal compositions identified for maximum solar spectrum absorption.

Abstract

Recently, a homogenization procedure has been proposed, based on the tight lower bounds of the Bergman-Milton formulation, and successfully applied to dilute ternary nanocomposites to predict optical data without using any fitting parameters [Garcia et al. Phys. Rev. B, 75, 045439 (2007)]. The procedure has been extended and applied to predict the absorption coefficient of a quaternary nanocomposite consisting of Cu, Ag, and Au nanospheres embedded in a SiO2 host matrix. Significant enhancement of the absorption coefficient is observed over the spectral range 350-800 nm. The magnitude of this enhancement can be controlled by varying the nanosphere diameter and the individual metal volume fraction with respect to the host matrix. We have determined the optimal composition resulting in enhanced broadband (350nm-800nm) absorption of the solar spectrum using a simulated annealing algorithm. Fabricating such composite materials with a desired optical absorption has potential applications in solar energy harvesting.