Micro-Nano Composite Structures: General Resolution for Transparent-to-Multicolored Electrochromic Supercapacitors Assembly

With the objective to fully exploit the energy-saving advantages of the electrochromic (EC) phenomenon for potential applications in related fields such as smart windows and displays, while conferring integrated functionality to a single device, it is urgent to explore a commonly applicable device construction strategy. Herein, the typical high performance polymer (HPP) materials of poly(arylsulfones) and poly(aryl ketones), each capable of achieving transparent-to-multicolored variations, are taken as the breakthrough point, and ingeniously coupled with the conductive substrate modification layer (SnO2) and the ion storage layer (V2O5), to construct electrochromic supercapacitors (ECSs) capable of fully unlocking the extraordinary intrinsic performances from the active substances. SnO2 nanosheets were utilized to construct the microstructure of the active layers with uniform porosity with a view to improving the response speed of the system in response to the input electrical signals. Alternatively, modified V2O5 nanowires, which were highly compatible with the EC materials and did not interfere with their color-changing effect, were specially identified as the counter electrode materials to facilitate the specific function. Benefiting from the porous composite structure, the delicately matched poly(bis(4-(diphenylamino)phenyl)sulfone) (P-TST) device with P-TST@SnO2/V2O5 structure boasted an optical contrast ratio of 68.07%, a reduction in coloring time by more than 2/3, and a near-doubling coloration efficiency. Additionally, the construction strategy is beneficial to the capacitive properties as well. There is a perfectly adequate compatibility between material variety and multi-functionality. Such an alternative and versatile construction strategy is justified to inject vitality into the development of electrochromism in multifunctional smart windows or displays.