Trending towards reduced power and mass budget on satellites with a longer mission life, there is a need for a reliable thermal control system that is more efficient and cost-effective. By developing a passive, multifunctional, modulating multilayered coating based on the thermochromic material, VO2, a "smart" radiator device (SRD) will allow for thermal control with a decrease in the spacecraft power budget. The objective of this work is to validate multimaterial-layered films deposited via conventional sputtering methods and Atomic Layer Deposition (ALD) to lower the emissive transition point of VO2 and demonstrate the applicability of depositing on novel three dimensional geometries. The objective of this work is to demonstrate multimaterial-layered films deposited via conventional sputtering methods and ALD and its benefit to GSFC in providing a manufacturing method to meet NASA's Nanotechnology Roadmap. The Nanotechnology Roadmap is broken down into four major themes where the work we are proposing falls under the Engineered Materials & Structures category. Within this category we seek to develop enabling thin-film technologies that facilitate the current state of the art in coatings specifically in thermal protection for the full spectrum of spacecraft platforms from large structures to 1 U CubeSats. Passive thermal films of vanadium oxide, VO2, have the unique ability to transition from a semiconductor to a metal state at a specific temperature with a change in emissivity. This transition occurs at 68 C with the emissivity changing from e = .4 to e = .9. In order to tune lower the transition state temperature switch point while increasing the emissivity delta a multi-layered structure is proposed.
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