Copper Black Coatings for the Absorption of Solar Concentration With an APPJ SiO2 Super-Hydrophobic Protection

Solar thermal energy can be captured on absorbent surfaces, but coatings tend to deteriorate, due to changes in hue, thermal shocks, or detachment of all layers. There is a great challenge in reducing the deterioration because of environmental factors such as corrosion, impact, and dust control, among others. The absorbent coatings interact with the incident solar radiation transforming it as heat energy, and selectivity allows a low emissivity. In this work, a three-layer system on copper is proposed. An anodized CuO or black copper layer as an absorbent with high absorptance is proposed. A protective layer was added to extend the lifetime of use while preserving the functional characteristics of the absorbent black layer by using SiO2 deposited by atmospheric pressure plasma jet (APPJ) using hexamethyldisiloxane. A selective layer of aluminum was deposited by physical vapor deposition (PVD). Thermal shocks were applied by concentrated solar power with a Fresnel lens to represent sudden temperature changes in the radiation absorbent when the weather changes.