Preparation and thermal stability on non-vacuum high temperature solar selective absorbing coatings

Spectrally selective TiAl/TiAlN/TiAlON/TiAlO coating was deposited on stainless steel and copper substrates using a multi-arc ion plating system. The structure, morphology, optical reflectance and electrical resistivity were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), spectrophotometer and four-point probe meter, respectively. The results show that the coating exhibits high absorptance (−0.9) and low emittance (0.09–0.19). The coating remains stable in air up to 650°C for 1h. These properties are of extraordinary interest in solar thermal power generations and energy saving buildings.