Preparation and properties of solar selective absorbers based on AlCuFe and AlCuFeCr thin films: industrial aspects

摘要

solar selective absorbers for thermal energy applciatiosn can be realized with films of quasicrystal forming alloys.Absorbers were produced by sputtering thin films of AlCuFe and AlCuFeCr.Alumina and floatglass were used as dielectric antireflective coatings,which are necessary for the requried optical properties.For applciations,several aspects are of importance: high solar absorptance and low thermal emittance hav eto be achieved.Moreover,the coatings have to show good adhesion and stability with respect to oxidation in air at elevated temperatures and exposure to humidity and condensation of water.the present study emphasizes these aspect,especially degradation stability,for coatings deposited on technical copper foils with large roughness.Oxidation stability is achieved easily,while humidity stability depends strongly on the choice of mateirals.The combination AlCuFeCr/floatglass turned out to be stable,while the combination AlCuFe/alumina is destroyed rapidly.