Solar energy is one of the renewable resources of energy thathas an infinite supply and is easily accessible. The photon energyfrom the sun can be converted to useable thermal energy byconcentrating it onto a highly absorbing material, which has a lowemissivity [1,2]. This objective can be achieved by using solar absorbers,which are coatings made from various combination ofmaterials, with microstructures that are able to absorb incidentphotons from solar radiation and then converting it to a hightemperature thermal energy [1]. The photo-thermal conversionefficiency of the solar absorber can be enhanced by employing aspectrally selective coating that exhibit high solar absorptance overthe entire solar spectrum (0.3e2.5 mm), and low emissivity in theinfrared region (2.5e25 mm) [2,3]. An ideal spectrally selectivecoating should exhibit an absorptance ‘‘a ¼ 100 in the solar wavelengthrange and emittance ‘‘ε ¼ 000 in the infrared wavelengthregion at high operating temperatures [4,5]. To achieve thesedesired characteristics, various concepts such as cermet coatingsand absorber-reflector tandem have been used by several researchgroups [6e9]. However, a multilayered absorbers based on metallicoxide coatings such as Cr2O3, AlxOy, MoO3, WOx, HFO2, Al2O3 etc., have also attracted considerable attention due to their opticalproperties and good thermal stability [10e16]. A multilayer stackessentially consists of thin semi-transparent metal layer betweentwo dielectric layers can be designed to be efficient as a spectrallyselective coating.