Foldable All‐Solid‐State Supercapacitors Integrated with Photodetectors

Recent development in flexible electronics has promoted the increasing demand for their energy storage systems that will be lightweight, thin, flexible, and even foldable. Although various flexible supercapacitors recently have been successfully developed, the design and assembly of highly foldable supercapacitors have received less attention. Furthermore, foldable supercapacitors are in general operated independently with other electronics, resulting in some space and energy consumption from the external connection system. Therefore, the authors fabricate the foldable all‐solid‐state integrated devices with supercapacitor and photodetector functions in a simplified and compact configuration based on single‐walled carbon nanotube films and TiO₂ nanoparticles. The integrated devices not only retain the intrinsic capacitance behavior but also show excellent sensitivity of detecting white light. More importantly, the capacitance behavior of integrated devices remains almost unchanged and the photodetector behavior is quite stable even folded by 180° due to their unique integrated configuration. Such rational design of all‐solid‐state integrated devices will pave the way for assembling energy storage devices and other electronics into highly flexible and foldable integrated devices.