Wide-Angle Broadband Solar Absorber Based on Multilayer Etched Toroidal Structure

In this study, we propose a wide-angle broadband solar absorber based on multilayer etched toroidal structure. It is composed of a top layer Ti, W, and Si3N4 multilayer material, a silica insulator, and a Ti substrate. The average absorption from visible to mid-infrared wavelengths is 94.2%. The absorption bandwidth above 90% absorption is 3092 nm, and the peak absorption is 99.9%. The absorber achieves a perfect collection of incident solar energy caused by the combination of the local surface plasma resonance at the top layer of this absorber and the propagating plasma resonance in the lower insulator layer. The results are verified by applying impedance matching theory. Then, the effects of different structural geometrical parameters, polarization angles, and TE and TM incidence angles on the absorption are discussed. In addition, this absorber captures solar energy across the entire solar spectrum. Finally, we demonstrate that the absorber has a solar thermal conversion efficiency of more than 90% in the temperature range of 100 –900 °C. This absorber has good application prospects in the fields of solar absorbers, solar thermal photovoltaic devices, and solar thermal electronic devices.
Source: Plasmonics - Category: Biomedical Science Source Type: research