SOLAR SELECTIVE COATING FOR SOAR ENERGY COLLETOR / ABSORBER TUBES WITH IMPROVED PERFORMANCE AND A METHOD OF PRODUCING THE SAME

摘要

The invention discloses an improved nanoporous composite solar selective absorber coating with an antireflective layer with protective property and another antireflective layer having an excellent optical absorptance with a solar absorptance (95%), low thermal emissive property (0.09-0.19) at 100 to 300°C, excellent corrosion resistant property to withstand acceleration corrosion test, 200hrs and thermal stability at a temperature up to 300°C capable of coating on stainless steel substrate (1a) comprisinga) a solar selective absorber layer (2a), having a nanoporous composite oxide layer consisting of Cr, Mn and Fe; b) an antireflective layer with protective property (1st antireflective layer, 3a) consisting of material selected from Si02-Zr02 solgel nanocomposite deposited over the said solar absorber layer (2a); and c) another antireflective layer (2nd antireflective layer, 4a or 4b) consisting of material selected from SiC2 nanoparticles having spherical shape (4a); nanoporous MgF2 nanoparticles having hexagonal shape (4b). It also discloses a method of producing said coating for solar energy collector / absorber tubes.