Design of Hierarchical Flower-Like ZnO for Enhanced Lunar Dust Protection in Thermal Control Coatings

Thermal control coatings are crucial for regulating temperatures in spacecraft. However, contamination from lunar dust presents a significant challenge to their thermal control performance. This study introduces an innovative ZnO-based thermal control coating designed to resist contamination by lunar dust. By engineering a multiscale surface roughness with flower-like ZnO pigments and valley-filling ZnO nanorods, the coating enhances nano-roughness and reduces the contact area with dust, thereby decreasing adhesion force and minimizing particle retention. While maintaining thermal control effectiveness comparable to traditional coatings, it demonstrated a lower dust adhesion force of 3.1 nN, which is one-third that of conventional coatings. Furthermore, following dust exposure experiments, the coating exhibited minimal dust contamination, with a lower change in the solar absorption to emittance ratio ( Δα s /ε = 0.04), indicating little degradation in thermal control performance. This synergistic combination of hierarchical roughness and valley-filling nanorod structures provides a promising dust mitigation solution for spacecraft thermal control coatings, showcasing potential for future lunar, Martian, and other planetary missions.