Solar radiation energy absorber

摘要

A solar energy absorber consisting of a metallic copper or copper alloy substrate and a black to dark brown copper oxide coating on its surface. The copper oxide coating is formed by treating the surface of the substrate with an aqueous alkaline solution containing peroxodisulfuric acid or an inorganic peroxodisulfate. The solution may be activated by adding an oxidizing agent or applying ultraviolet or ultrasonic irradiation.