Ti<sub>3</sub>C<sub>2</sub>T<sub><i>x</i></sub>‐MXene‐Based Color‐Indicative All‐Organic Electrochromic Supercapacitors
Bhumika Sahu, Mayank K. Singh, Love Bansal, Deb Kumar Rath, K. Dhirendra, Rajesh Kumar
Abstract
An all‐organic multifunctional solid‐state electrochromic supercapacitor has been designed by utilizing 2D‐MXene and a combination of viologen and polythiophene. The 2D MXene is synthesized using selective etching method and properly characterized; afterward, it is doped in ethyl viologen (EV) and a solid‐state electrochromic supercapacitor device is prepared having poly‐3‐hexylthiophene (P3HT) as complementary electrode. The prepared device gives high optical contrast (OC) (≈85%) and coloration efficiency (CE) (≈340 cm 2 C −1 ) with ≈1 s of switching time in the visible spectrum at 515 nm. A similar color modulation is observed in NIR region also. Along with high electrochromic properties, the device takes almost 23.1 s for discharging and 6.7 s for charging, giving high Columbic efficiency due to the pseudocapacitor‐type charge storage property providing necessary electrons for the redox reaction to occur. The current study proposes a new MXene‐based recipe for designing multifunctional electrochromic supercapacitors with a promise for practical use.