Versatile Strategy to Design Flexible Planar-Integrated Microsupercapacitors Based on Co₃O₄-Decorated Laser-Induced Graphene

Flexible planar microsupercapacitors (MSCs) have become one of the most crucial energy storage devices for wearable and portable electronics on account of the superiorities of miniature size and easy integration with on-chip electronics. Under this background, we creatively design a versatile and facile strategy for in situ fabrication of flexible shape-controllable, planar microsupercapacitors based on Co3O4-decorated laser-induced graphene (LIG) on various substrates. This laser direct writing (LDW) patterning technique with advantages of simplicity, convenience, and low budget is applicable to customized polyimide films containing metal heterogeneous precursors coated on different flexible substrates to in situ generate metal oxide nanoparticles embedded in LIG patterning electrodes. These flexible designable-shaped, planar-integrated Co3O4/LIG MSCs exhibit excellent electrochemical performances, including high area-specific capacitances, excellent cycling stability, outstanding flexibility, and mechanical stability. Using this universal route, it can be proposed that flexible planar MSCs with desired shapes are fabricated on a variety of substrates for facilitating modular integration and biocompatibility to satisfy the requirements of microelectronics in the future.