Zirconium Carbide-Nitride Composite Matrix Based Solar Absorber Structures on Glass and Aluminum Substrates for Solar Thermal Applications
Abstract
Zirconium carbide-nitride absorber (ZrC-ZrN) and zirconium reflector tandem structures were prepared on glass and aluminum substrate, in conjunction with zirconium oxide (ZrOx) anti-reflection coatings, using DC/RF magnetron sputtering system. The solar absorption properties of zirconium carbide-nitride absorber layers were optimized by controlling nitrogen flow during synthesis process for optimal solar thermal response. X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM) measurements were carried out on fabricated absorber-reflector tandem structures to understand the structure-property correlation. We absorbed strong dependence of zirconium nitride fraction on solar thermal performance. We observed enhanced solar absorptance α ~ 0.86 and thermal emittance ε ~ 0.05 at room temperature for structures fabricated with optimized synthesis parameters. The optimized structures are stable up to 150 °C in the air without any significant degradation in their solar performance.
Keywords
Solar selective coatings, Sputtering, Structure, Optical property, Thermal stability