We present the main results from the Horizon 2020 project Smart-Flex focusing on the development of variable emissivity optical solar reflector foils for radiative cooling in the space environment. The OSR coating is made of two functional blocks, namely a variable emitter topped by a low emissivity solar reflector. The variable emitter is a Perfect Metamaterial Absorber designed for strong and broadband plasmonic resonance absorption in the thermal IR. It consists of a metal back-reflector, a dielectric spacer, and an array of doped Vanadium Dioxide (W:VO2) EM micro-antennas that are switched-off through metal-to-insulator transition when the temperature drops below 10°C. The solar reflector is a wideband dielectric filter of about 30 layers made of materials that are transparent across the entire spectrum from the VIS to the thermal IR. All the layers of the two blocks are deposited by standard vacuum techniques, while the array is patterned by Nano Imprint Lithography (NIL).
Our experimental demonstration is fabricated onto a flexible Kapton foil with active metasurface area of 100x100 mm2, which achieves the initial requirements. The devices show a mechanically and thermally robust response which passed some critical ageing tests ageing tests including bending, thermal cycling and charged particle at doses equivalent to 2 years GEO. The presentation focuses on the various developments in materials, fabrication techniques and durability testing.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.