Comparative investigation of polyaniline and polypyrrole blending with ZIF-67 MOF: unravelling their influence on ZIF-67 supercapacitor performance

In the present work, the synthesis of ZIF-67/PANI and ZIF-67/PPy composites, derived from polyaniline (PANI), polypyrrole (PPy), and ZIF-67 offers considerable potential in the application of supercapacitors. The synthesized ZIF-67/PANI and ZIF-67/PPy composites were characterized using X-ray Diffraction (XRD), Fourier-transform Infrared Spectroscopy (FTIR), Ultraviolet-Visible Spectroscopy (UV-Visible) and Field Emission Scanning Electron Microscopy (FESEM). The fabricated electrodes of ZIF-67/PANI and ZIF-67/PPy composites were studied under different KOH molarity solutions as electrolytes, via 2 M, 4 M, and 6 M in an electrode system. The ZIF-67/PPy and ZIF-67/PANI composites exhibit effective results in a 6 M KOH electrolyte solution, with specific capacitances of 417 F g^-1 and 312 F g^-1, respectively, at a current density of 1.8 A g^-1. Additionally, Electrochemical Impedance Spectroscopy shows the least series resistance in 6 M KOH solution compared to 2 M and 4 M KOH. The electrodes of a ZIF-67/PANI and ZIF-67/PPy composites Maintain their cyclic stability up to 96% and 84%, respectively, after 1000 cycles, compared to ZIF-67. The ZIF-67 composites demonstrate exceptional energy storage capabilities, which assist in developing energy storage devices and other electrochemical devices.