All Transparent-Stretchable Electrochromic-Supercapacitor Wearable Patch Device.

Flexible-stretchable electrochromic-supercapacitor systems are widely considered as a promising multi-functional energy storage device that eliminates the need for an external power source. Nevertheless, the performance of conventional designs deteriorates significantly as a result of electrode/electrolyte exposure to atmosphere as well as mechanical deformations for the case of flexible systems. In this study, we suggest an all transparent-stretchable electrochromic-supercapacitor device with ultrastable performance, which is consisted of the Au/Ag core-shell nanowire embedded polydimethylsiloxane (PDMS), bi-stacked WO3 nanotube/PEDOT:PSS, and polyacrylamide (PAAm) based hydrogel electrolyte. Au/Ag core-shell nanowire PDMS integrated with PAAm based hydrogel electrolyte prevents Ag oxidation and dehydration while maintaining ionic and electrical conductivity at high voltage even after 16 days of exposure to ambient conditions and under application of mechanical strains in both tensile and bending conditions. WO3 nanotube/PEDOT:PSS bi-stacked active materials maintain high electrochemical-electrochromic performance even under mechanical deformations. Maximum specific capacitance of 471.0 F g-1 was obtained with a 92.9% capacity retention even after 50,000 charge-discharge cycles. In addition, high coloration efficiency of 83.9 cm2 C-1 was shown due to the dual coloration and pseudocapacitor characteristics of WO3 nanotube and PEDOT:PSS thin layer.