A tungsten-based solar absorber with a strip-combined starfish structure with high photothermal conversion efficiency and low radiative heat loss
Journal
Physical Chemistry Chemical Physics
Journal Volume
27
Journal Issue
48
Start Page
25868
End Page
25875
ISSN
14639076
Date Issued
2025-12-28
Author(s)
Abstract
We propose a tungsten-based broadband resonator capable of achieving near-perfect solar absorption with suppressed radiative heat loss. Across the entire solar radiation spectrum, the absorber exhibits a spectrally integrated total solar absorptance of 95%. Taking into account the thermal emission under an operating temperature of 100 °C, the photothermal conversion efficiency remains as high as 92–93%. Using particle swarm optimization, the initial square-based structure is transformed into adjacent and closely packed strip structures with multiple lengths to achieve enhanced solar absorption. The analysis uses finite-difference time-domain simulations, considering light polarization, incident angle, and structural defects. We proposed a new metamaterial structure with multiple strips that are more efficient and have a simpler geometric structure, as compared to multilayer films, pyramids, or cone structures, which mostly exhibit substantial radiative heat losses. The structure is composed of a W/SiO2/W (metal–insulator–metal) configuration, with a surface nanostructure pattern composed of low-emissivity tungsten, with fabrication error-tolerant computational design.
Publisher
Royal Society of Chemistry
Type
journal article