SWCNT-bridged laser-induced graphene fibers decorated with MnO2 nanoparticles for high-performance flexible micro-supercapacitors

Hybrid nanocomposites comprised of metal oxide nanoparticles and three-dimensional (3D) graphene possess the advantages of metal oxide and graphene, which have generated extensive attention. Here, we fabricate flexible micro-supercapacitors (MSCs) based on hybrid materials of single-walled carbon nanotubes (SWCNT)-bridged laser-induced graphene fibers (LIGF) decorated with manganese dioxide (MnO 2 ) nanoparticles . SWCNT is deposited on the LIGF surface and the space between LIGF, which can bridge LIGF to form more conductive paths and provide more active areas to grow with MnO 2 nanoparticles . Profiting from the synergistic effect between conductive SWCNT-bridged LIGF network and the MnO 2 nanoparticles with high theoretical capacitance, the obtained flexible MSCs based on LIGF-C4/MnO 2 hybrid electrodes deliver an outstanding areal capacitance of 156.94 mF cm −2 , which is about 8 times higher than that of LIGF-MnO 2 based MSC (20 mF cm −2 ). Additionally, the LIGF-C4/MnO 2 MSCs also exhibit considerable areal energy density of 21.8 μWh cm −2 , long-term cycling stability, remarkable modular integration capability, and exceptional mechanical flexibility (with 90.5% capacitance retention after 1200 bending cycles). Therefore, the design of hybrid electrode materials proposed in this work offers a facile and novel method to develop flexible energy storage devices with high performance, suggesting great prospects for applications in future various wearable electronics.