Broadband high thermal radiation nanoscale near-perfect solar energy metamaterial for thermal applications

Metamaterials designed with nanostructures can effectively convert solar energy into thermal energy, facilitating various applications such as photovoltaic systems, energy harvesting, and thermal applications. This study investigates a periodic array of square-shaped nickel nanostructures metasurface aimed at optimizing solar radiation capture, resulting in an aggregate absorption rate of 98 % within 400–8000 nm range. This broadband absorption results from the localized surface plasmon resonance phenomenon. The proposed device shows a near perfect matching with the solar power radiation AM 1.5 model curve, achieving a solar absorption rate of above 98 %. Moreover, the proposed device shows excellent performance under the blackbody thermal radiation curve with a high thermal radiation efficiency of 95 % at 873 K. Further attributes of the proposed device include hardiness to different light wave polarization conditions and incident angles. Additionally, we have verified the broadband high absorption characteristics through an examination of impedance matching theory, in sighting the distribution of electric field within its structure and impact on the absorption rate with the variation in the different parameters of the unit cell. The findings indicate that the proposed structure exhibits potential for industrial and commercial applications including photovoltaic system, energy harvesting and thermal applications.