A novel binary composite of CuCoNi-MOF/MoO3 with exceptional capacitance as electrode material for supercapacitors

Abstract

Metal-organic framework (MOF), a new type of electrode material with a porous structure, has shown promise as a good choice for supercapacitors in the next generation of energy storage devices. These research endeavors initiated the development of a doping technique and the creation of a composite material using solvothermal synthesis. This study involves the successful synthesis of CuCo-MOF and CuCoNi-MOF by introducing Co and Ni metals into the Cu-MOF. The CuCoNi-MOF is then combined with MoO3 to form a novel binary composite known as CuCoNi-MOF/MoO3. These prepared materials are then subjected to several physiochemical and electrochemical characterization techniques. The electrochemical characteristics of the prepared samples are estimated using a three-electrode cell setup. The analysis included cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charge/discharge (GCD). The examination of the CV reveals that the binary composite CuCoNi-MOF/MoO3 exhibits exceptional capacitance (937.5 Fg−1 at 5 mVs−1) in comparison to the other materials that were synthesized. Moreover, the GCD study reveals that it has a capacity of 1364.69 Fg−1 at 0.5 Ag−1. Furthermore, it retained 91.5 % of its capacity after 5000 cycles demonstrating its exceptional stability. Owing to the exceptional electrochemical properties of CuCoNi-MOF/MoO3, it is employed as the positive electrode and activated carbon (ActC) as a negative electrode for device fabrication. The supercapattery (CuCoNi-MOF/MoO3||Act-C) showed an excellent specific capacitance of 218.83 Fg−1 at 1 Ag−1 along with an outstanding energy density of 59.57 Wh.kg−1 and power density of 704.9 W.kg−1. Moreover, the assembled supercapattery device shows remarkable stability of 95.2 % at 10 Ag−1 after 15,000 cycles.