The harsh conditions that equipment, satellites, and spacecraft are subject to in space pose significant challenges. Electronic systems must be protected from extreme heat and cold, while storage containers holding liquid propellants must be shielded from solar radiation.
With the support from a NASA Early Career Faculty Award, Shankar Narayanan, an assistant professor of mechanical, aerospace, and nuclear engineering at Rensselaer Polytechnic Institute, aims to develop new materials that can protect objects from extreme radiation and temperature variations in space — an important step toward enabling long-distance space exploration.
“The overall objective is to understand how different geometries and materials affect the optical and thermal characteristics of coatings,” Narayanan said. “Unless you understand that, there’s no way to design something that works.”
Narayanan and his team will explore how different polymers and metals can be combined to provide this type of protection. They will study different nanomaterials to understand how the underlying geometry and structure affect the material’s reflective behavior.
“You can take these fundamental building blocks consisting of nanoscale beads, cylinders, and fibers, arrange them to form a stacked layer, and you can get some really interesting reflective behavior quite different from the constituent materials,” Narayanan said.
Computational studies performed by Narayanan’s lab revealed that, when fabricated in different geometries, some materials could be more reflective than the coatings currently being used for insulation in space. He believes that if the materials and the geometries are optimally selected, the coatings could be mechanically robust, optically reflective, thermally insulating, and electrically conductive. Through this research, Narayanan and his team will fabricate novel multi-layered coatings of different geometries to test their performance for space applications.
This research could have beneficial applications on Earth, as well. Because it will be porous, Narayanan said, this type of coating may be useful as a filtering mechanism for oil-water separation, seawater desalination, food processing, biomedical applications, and energy storage. Since the coatings will have unique optical properties, they may also be used as coatings for buildings to decrease their energy consumption for heating and air-conditioning.