A review of cermet-based spectrally selective solar absorbers

Spectrally selective solar absorbers harvest solar energy in the form of heat. Solar absorbers using cermet-based coatings demonstrate a high absorptance of the solar spectrum and a low emittance in the infrared (IR) regime. Extensive work has been done to optimize cermet-based solar absorbers to achieve high performance by exploring different cermet (ceramic-metal composite) materials and film configurations through different preparation techniques such as electrodeposition, sputtering, pulsed laser deposition, and solution-based methods. In this article, we review the progress of cermet-based spectrally selective absorbers with high solar absorptance and low thermal emittance, such as Cr2O3, Al2O3, AlN, SiO2, and ZrO2 based cermets as absorption layers. We also present an outlook for cermet-based spectrally selective absorbers with high thermal stability and high conversion efficiency from sunlight to heat.