Robust Ionic Liquid Electrolytes for Reversible Electroplating of Mirrors

This proposal addresses the need for development of room-temperature ionic liquids (RTILs) for use in electrolytes for reversibly electroplating films with specific optical, emissive and electrical properties on demand. Target applications for these electrolytes are devices using reversible electroplating for tuning/regenerating functional surfaces, such as mirrors or thermal emitters, deployed on orbital platforms. Faraday and the University of South Alabama propose to develop RTILs and reversible electrochemical mirror (REM) devices that use reversible electroplating to control the transmission or reflection of light by electrochemically cycling between the reflective metal film and a transmissive surface. RTIL electrolytes for REM devices are attractive because their unique properties are suited as space compatible electrolytes. The low volatility of RTILs may prevent evaporation if exposed to vacuum, and their excellent chemical and thermal stability may enhance tolerance to orbital radiation. Phase II will optimize RTIL electrolytes for REM devices suitable for orbital deployment, develop CPS cleaning parameters to prolong device cycling lifetime, develop processing conditions to optimize device reflectance and transmission properties on demand, evaluate the impact of long cycle life on device components, develop the technology to a scale relevant to the USAF, and develop a technology transition plan and economic assessment.