Controllable layer-by-layer assembly of metal-organic frameworks/polyaniline membranes for flexible solid-state microsupercapacitors

We report a new type of flexible solid-state microsupercapacitors (MSCs) with high power density, excellent cycle life, and good mechanical flexibility. The MSCs are fabricated through the layer-by-layer (LBL) electrodeposition of porous polyaniline (PANI) and the metal-organic frameworks (MOFs) crystals on laser-induced graphene (LIG) substrate. Owing to the synergic effect of MOFs with highly porous structure and the PANI chains with the excellent conductivity, the resulting MSCs exhibit layer-dependent capacitance performance with the largest areal specific capacitance of 719.2 mF cm(-2) at a current density of 0.5 mA cm(-2), which is almost 370 times higher than that of MSCs prepared by the bare LIG. Meanwhile, the prepared MSCs retain more than 87.6% of their capacitances after 6000 cycles of charge-discharging test, demonstrating their promising cycling stability. Furthermore, the application of MSCs for the lighting of the light-emitting diode (LED) and their stable mechanical flexibility reveals their remarkable capability as the power supply for the small and wearable devices.