Flexible supercapacitors (FSCs) are promising power sources for wearable electronics, yet their performance is often limited by the use of rigid metallic current collectors. In this study, we presented a freestanding porous polyurethane/PEDOT:PSS/MnO x sandwich‐structured electrode fabricated through a straightforward solution‐based method. The design employed a flexible porous polyurethane (PC) film as the substrate, while high‐capacitance MnO x and MnO x /PEDOT (PM) composites were encapsulated between highly conductive PEDOT:PSS layers serving as the active materials. Leveraging the exceptional mechanical flexibility of the PC film, the high electrical conductivity of PEDOT:PSS, and the superior capacitance of MnO x and PM, along with their synergistic interactions including strong interfacial adhesion, rapid charge transfer, and efficient ion diffusion, the as‐fabricated PCS‐MPM‐PS electrode delivered a high areal capacitance (Ca) of 408.9 mF cm −2 (~371.2 F g −1 ) at 1 mA cm −2 . Furthermore, a solid‐state symmetric SC was fabricated using two identical PCS‐MPM‐PS electrodes, delivering a high Ca of 152.6 mF cm −2 at 1 mA cm −2 . Notably, this performance remained stable across various bending angles, demonstrating excellent mechanical flexibility and significant potential for use in wearable energy storage devices.
Sun et al. (Sun,) studied this question.