Engineering a 3D conductive polythiophene network with conformational locking for camouflaged wearable electrochromic-supercapacitor devices

Electrochromic-supercapacitor (EC-SC) devices demonstrate significant promise for future intelligent technologies, seamlessly combining dynamically adjustable optoelectronic characteristics with high-efficiency energy storage to address emerging demands in sustainable and energy-smart systems. However, the inability to synergistically improve electrochromic and capacitive properties in a single material has prevented its practical application. Here, we develop a conformational lock design strategy to prepare high-performance EC-SC materials by introducing 3D conductive networks through intramolecular noncovalent interactions and intermolecular hydrogen bonding. The synthesized EC-SC material poly(5,7-bis(4-fluorothiophen-2-yl)-2,3-dihydrothieno[3,4-b][1,4]dioxine) (PFTDT) demonstrates concurrent multifunctionality with favorable electrochromic property (79 % optical contrast at 930 nm), remarkable specific capacitance (348 F g^-1, 1 A g^-1), and robust optical/electrical bistability. Capitalizing on the superior multifunctional properties of PFTDT, we further engineer its-based flexible electrochromic-supercapacitor devices (FESDs) for camouflage energy supply. Such FESDs exhibit multi-color changes, as well as excellent stability against mechanical bending, which makes them promising for applications in scenes such as deserts, forests, and oceans. The conformational lock design strategy and the resulting high-performance PFTDT materials show significant promise for advancing reliable FESD, with potential applications extending to diverse scenarios, including wearable electronics.