High-temperature and abrasion-resistant metal-insulator-metal metamaterials

Selective solar absorbers (SSAs) with high performance are the key to concentrated solar power systems. Optical metamaterials are emerging as a promising strategy to enhance selective photon absorption, however, the high-temperature stability (>500 °C) remains as one of the main challenges for practical applications. Here, a multilayered metamaterial system (Al₂O₃/W/SiO₂/W) based on metal-insulator-metal Fabry-Pérot resonance effect has been demonstrated with high solar absorptance over 92%, low thermal emittance loss below 6% (100 °C blackbody), and significant high-temperature thermal stability: it has been proved that the optical performance remains 94% after 1-h thermal annealing under ambient environment up to 500 °C, and 94% after 96-h thermal cycle test at 400 °C. Outdoor tests demonstrate that a peak temperature rise (193.5 °C) can be achieved with unconcentrated solar irradiance and surface abrasion resistance test yields that SSAs have a robust resistance to abrasion attack for engineering applications.