Broadband polarization-insensitive and wide-angle solar energy absorber based on tungsten ring-disc array

Area of Science:

• Materials Science
• Renewable Energy Engineering
• Optics and Photonics

Background:

• Solar energy is a key clean energy source, with a broad solar spectrum from 295-2500 nm.
• Efficient absorption of this broad spectrum is crucial for effective solar energy utilization.

Purpose of the Study:

• To design and investigate a novel broadband solar energy absorber.
• To achieve high absorption efficiency across a wide solar spectrum using tungsten (W).

Main Methods:

• Utilized a four-layer ring-disk structure (SiO2-SiO2-W).
• Employed finite-difference time-domain (FDTD) simulations to analyze absorption performance.
• Investigated tunability via structural and geometric parameter variations.

Main Results:

• Achieved broadband solar energy absorption with a bandwidth of 1530 nm.
• Demonstrated absorption efficiency exceeding 90% within the target bandwidth, reaching 97% peak efficiency.
• Confirmed excellent polarization independence and performance from 0° to 60° incident angles.

Conclusions:

• The proposed tungsten-based absorber offers efficient broadband solar energy absorption.
• The design is simple to fabricate and suitable for photothermal conversion and solar energy harvesting.
• Tunable absorption spectra and wide-angle performance enhance its practical applicability.