A Low Driving-Voltage Hybrid-Electrolyte Electrochromic Window with Only Ferreous Redox Couples.

Even after decades of development, the widespread application of electrochromic windows (ECW) is still seriously restricted by their high price and inadequate performance associated with structural/fabrication complexity and electrochemical instability. Herein, a simple hybrid electrochromic system based on PFSA (perfluorosulfonic acid)-coated Prussian blue (PB, Fe [Fe(CN)]) film and Ferricyanide-Ferrocyanide ([Fe(CN)]/[Fe(CN)])-containing hybrid electrolyte is reported. The PB film and the [Fe(CN)]/[Fe(CN)] couple show near redox potentials well inside the electrochemical window of water, resulting in a low driven voltage (0.