Synthesis and assessment of an efficient black coating with nanostructured additives for solar applications

This study presented innovative black selective coating systems that are stable, long-lasting, and improve solar absorber performance in solar thermal collectors. Several types of black coatings with nanostructure additives were synthesized and investigated. Nano graphene-based paint, nano copper-based paint, multilayered nano copper-nano graphene-based paint, and a mixed ratio of nano copper- and graphene-based paint were prepared. The multilayered black coating mixed with nano copper and nano graphene additives displayed the lowest reflection values. Also, the multilayered paints containing copper and graphene nanoparticles showed higher stability on exposure to UV irradiation for 500 h. From the bench scale results, the maximum recorded temperature reading was 85°C at 12 a.m. under 500 W/m² solar intensity. The annual production cost for solar selective paint will be 2.561095 million US$, with a production cost per ton of $3880.4.