Effect of Magnetite Nanoparticles’ Modification on Optical Properties of Solar Absorber Coatings

The effect of magnetite nanoparticles on the optical characteristics of a thermal control coating (where alpha(s), is solar absorptance, and epsilon is emittance) of the "true absorber" class as well as the effect of magnetite nanoparticles on optical coefficient changes of the coating under the influence of proton radiation were studied. It was revealed that the iron oxide nanoparticles added into an enamel increased the solar absorptance from 0.95 to 0.97, and the emittance was increased from 0.92 to 0.94. Experiments on irradiation of the coating samples by 20 keV protons showed stability of the optical properties of the coating. Injection of magnetite nanoparticles led not only to improvement of the optical properties of the coating but also to a decrease of the degradation of the coating surface.