Low-cost black Cu–Ni alloy coatings for solar selective applications

The development of the Cu–Ni alloy coating as a selective surface for solar energy use is reported. The coatings were deposited by electrodeposition using Hull cell. Effects of electrolyte concentration and operating parameters on the appearance and optical properties of the coating were studied. Deposition parameters were optimized to achieve high solar absorptance alpha α=0.94 and low emittance epsilon ε=0.08. The elemental composition and morphology were evaluated by SEM and energy dispersive X-ray diffraction analysis (EDAX). The coating may be promising for solar collector panels used in domestic water heaters.