Optical properties and radiation stability of SiO2/ZnO composite pigment prepared by co-sintering method

Thermal control coatings (TCCs) are an essential part of the thermal control systems in the spacecraft. Solar absorptance and emittance are the key performance parameters of TCCs. To develop an ultra-low solar absorption and stable inorganic TCCs for surface radiator, different TCCs were prepared by co-sintering ZnO and SiO 2 nanoparticles to form Zn 2 SiO 4 /SiO 2 pigment in this work, and the optical properties and radiation stability were systematically studied. It is found that the coating based on composite pigment has high reflectivity in the ultraviolet band and excellent optical performance possessing the low solar absorption of 0.06. In addition, the Zn 2 SiO 4 /SiO 2 coating demonstrates the highest proton and electron radiation stability because that SiO 2 between Zn 2 SiO 4 particles acts as the relaxation center of the defects caused by radiation.