Integrated Thermoelectric Design Inspired by Ionic Liquid Microemulsion-Based Gel with Regulatable Dual-Temperature Responsiveness

The concept and principles of chromatic engineering of electrolytes have demonstrated charming prospects for constructing pluralistic electrochromic devices. Here, we develop a synthetic design bearing thermochromic and electrochromic behaviors based on the ionic liquid (IL) microemulsion-based gel, driven by the intrinsic thermodynamic stability of microemulsion and ionic conductivity of IL. The prepared gel can tune light-scattering behaviors as the droplet expanded or aggregated when the temperature is out of its thermodynamically stable temperature range. Not only that, oil-phase IL ([EMIM]TFSI) as well as introduced LiCl and LiTFSI endows it with satisfactory ionic conductivity, making it able to be utilized as a free-standing electrolyte layer for the electrochromic smart window. Therefore, the fabricated smart window based on this gel and WO3 electrochromic layer successfully realizes dual-stimuli responsiveness for both temperature and electric field, possessing energy-saving combined with privacy protection function. In addition, the component compatibility of microemulsion allows the harmonious introduction of hydrophilic antifreeze moisturizer ethylene glycol (EG) and hydrophobic ultraviolet absorber 2-hydroxy-4-(octyloxy)benzophenone (2H4MBP), which further promotes the multifunctional integration of a smart window for the strengthened safety factor, anti-freezing, anti-drying, and anti-UV capabilities. Finally, we extend the application of the IL microemulsion-based gel to an ionic writing plate based on the same electrochromic mechanism. In brief, this innovative preparation method paves the way for multifunctional electrochromic devices.