Highly color tunable, electrochromic energy storage devices based on dye-modified ion gels

In this work, we proposed a facile strategy to achieve high color tunability of electrochromic supercapacitors (ECSs) with tungsten trioxide (WO₃) and nickel oxide (NiO) combination as EC materials. To achieve high color tunability, we applied a small amount of rhodamine (1:10³ wt%) as dyes and achieved a wide color map (e.g. blue, yellowish, and magenta). Hence, to expand the color map, we mixed dyes, controlled the concentration of dyes, and controlled the ratio of dye solutions therefore successfully expanding the color map (e.g. purple, navy, and red) and including highly reliable charging/discharging cyclic stability (83.6 % after 10,000 cycles), change in transmittance and galvanostatic charging/discharging curve synchronized well simultaneously and therefore energy storage amount is indicated visually For last, we fabricated practical feasibility of multicolor ECSs successfully. ECSs in this work have the potential to be ECSs applications for the next generation of smart windows as energy storage displays.