A Simplified All-polymeric Electrochromic Variable Emittance Coating for Smart Thermal Management

摘要

In recent years, electrochromic devices (ECDs) as an actively thermal control coatings have attracted much attention due to their reversibly and persistently emittance-tuning properties, fast switching times, high contrast ratios, and widely application potentials. In order to develop a smart variable emittance thermal control coating, we here reported on a flexible solid-state electrochromic devices based on soluble polyaniline by simply fabrication process. Devices were assembled in sandwich configuration of electrochromic materials on flexible PET substrate and a Li~+ doped polyacrylonitrile as a solid polymer electrolyte. The emissivity performance of this ECD was discussed in view of the thickness of active layer and the applied voltage. The emittance of our ECD can be tuned from 0.46 to 0.75 without any fine optimization, which is similar with that of other solid-state ECDs. The major advantage of this work is that the electrochromic variable emittance coating can be prepared using simple process, such as spin coating and spay coatings. These methods not only do not require any special equipments and vacuum working conditions, but also are easily applied for large area process. This study may open new avenues in the development of flexible electrochromic devices for spacecraft thermal control.