Investigation of double-layer coating pigmented with CuO particles of different concentrations on aesthetic and thermal aspects

The pigmented coating with high near-infrared reflectance against solar irradiation is drawing more and more attention in recent years considering both aesthetic and thermal aspects. In this study, a new approach of using double-layer pigmented coating with different volume fractions of CuO submicron particles is proposed to achieve better performance. Comparison of the calculated spectral reflectance of the double-layer coating with the uniformly pigmented coating (single layer) shows that the double-layer coating with a higher volume fraction in the upper layer can significantly reflect the solar irradiation especially in the near-infrared region while maintaining the same color appearance. Furthermore, coatings with different volume fraction distributions, thicknesses, particle diameters, as well as substrate conditions are investigated. The performance may be optimized using a set of carefully designed volume fraction distribution of the double-layer coating, thickness of the coating, particle sizes, over the standard white substrate.