Theory of random nanoparticle layers in photovoltaic devices applied to self-aggregated metal samples

TL;DR

This paper develops a theoretical model for random nanoparticle layers in photovoltaic devices, validated by experiments, to improve optical performance using rigorous electromagnetic simulations of self-aggregated metal nanoparticles.

Contribution

It introduces a novel theoretical approach for modeling arbitrary random nanostructure layers based on measured particle distributions and validates it with experimental data.

Findings

The model accurately predicts optical spectra of nanoparticle layers.

Self-aggregation method produces reproducible nanoparticle distributions.

The methodology enhances the design of nanoparticle layers for photovoltaics.

Abstract

Random Al and Ag nanoparticle distributions are studied on varying substrates, where we exploit the nanosphere self-aggregation method (NSA) for fabrication. Relying on the measured particle size distributions of these samples, we develop a theoretical model that can be applied to arbitrary random nanostructure layers as is demonstrated for several distinct NSA samples. As a proof of concept, the optical properties of the exact same particles distributions, made from the quasi random modeling input with electron beam lithography (EBL), are investigated from both theory and experiment. Our numerical procedure is based on rigorous solutions of Maxwell's equations and yields optical spectra of fully interacting randomly positioned nanoparticle arrays. These results constitute a new methodology for improving the optical performance of layers of nanoparticles with direct application to enhanced photovoltaics.