Facile Preparation of Varisized ZIF‐8 and ZIF‐8/Polypyrrole Composites for Flexible Solid‐State Supercapacitor

Abstract We have successfully synthesized zeolitic imidazolate framework‐8 (ZIF‐8) with controlled sizes and morphology by a facile method in methanol solution. Then the varisized ZIF‐8 coated on the carbon nanotube film (CNTF) and further electrochemically deposited polypyrrole (PPy) to give flexible porous electrodes (noted as PPy/XZIF‐8‐CNTF). Electrochemical dates show that the PPy/lZIF‐8‐CNTF electrode prepared by large size ZIF‐8 exhibits an exceptional areal capacitance (264.8 mF cm −2 ) at the current density of 1.0 mA cm −2 . We also assembled and tested a PPy/lZIF‐8‐CNTF symmetric solid‐state supercapacitor, which shows excellent areal capacitance (143.3 mF cm −2 ) at the current density of 0.4 mA cm −2 . The device also exhibits good cycle stability and flexibility.