Freestanding solid-state micro-supercapacitor based on laser-patterned nanofibers

In this paper, we present a novel fabrication for freestanding solid-state micro-supercapacitor (MSC) with interdigital carbon nanotube (CNT)/nanofibers electrode layer, gold current collector and the solid-state electrolyte-substrate, which, for the first time, combines electrolyte transferring with laser patterning process. With the in-planar electrode and electrolyte-substrate layout, the dimension of MSC could be greatly decreased. Meanwhile, taking advantage of electrospinning nanofibers with large surface-area and CNTs with high conductivity, the line-width finger (200 μm) of MSC exhibits high areal capacitance (15.6 mF/cm
²
), good energy and power density. In addition, the capacitance retention retains more than 83% after 2,000 cycles which performs stable and excellent electrochemical performance. Therefore, such flexible freestanding MSC shows great potentials to satisfy the requirements of miniaturized energy systems and wearable devices.