Toward a Better Understanding of the Photothermal Heating of High-Entropy-Alloy Nanoparticles

TL;DR

This paper introduces a theoretical method to analyze the optical and photothermal properties of FeCoNi high-entropy alloy nanoparticles, demonstrating accurate predictions of temperature rise and optical behavior that align with experimental data.

Contribution

It presents the first systematic theoretical approach to model high-entropy alloy nanoparticle optical and thermal properties, simplifying complex alloy analysis.

Findings

Accurately predicts absorption spectra of FeCoNi nanoparticles.

Shows temperature rise predictions match experimental data.

Reveals iron nanoparticles as effective models for high-entropy alloys.

Abstract

We present a theoretical approach, for the first time, to investigate optical and photothermal properties of high-entropy alloy nanoparticles with a focus on FeCoNi-based alloys. We systematically analyze the absorption spectra of spherical nanoparticles composed of pure metals and alloys in various surrounding media. Through comparison with experimental data, we select appropriate dielectric data for the constituent elements to accurately compute absorption spectra for FeCoNi-based high-entropy-alloy nanoparticles. Then, we predict the temperature rise over time within a substrate comprised of Fe nanoparticles exposed to solar irradiation and find quantitative agreement with experimental data for FeCoNi nanoparticles reported in previous studies. The striking similarity between the optical and photothermal behaviors of FeCoNi nanoparticles and their pure iron counterparts suggests that iron nanoparticles can effectively serve as a model for understanding the optical and thermal response of FeCoNi-based alloy nanoparticles. These findings offer a simplified approach for theoretical modeling of complex high-entropy alloys and provide valuable insights into their nanoscale optical behavior.