Development of nickel metal organic frameworks/reduced graphene oxide composite for supercapattery applications

Abstract

The demand for advanced energy storage devices that offer high power density while maintaining a high cycle life has become increasingly important in various applications. This thesis explores the feasibility of utilizing a composite material comprising nickel metal-organic framework (Ni-MOF) and reduced graphene oxide (rGO) for supercapacitor applications. Using a solvothermal method, we synthesized the Ni-MOF/rGO composite and analyzed its structural and morphological properties using diverse characterization techniques. The composite demonstrates a synergistic interaction of Ni-MOF's porous nature and rGO's exceptional conductivity. To evaluate its performance as a supercapattery material, we conducted electrochemical tests such as cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD). The CV analysis displays well-discernable redox peaks, indicating the supercapattery behavior of the Ni-MOF/rGO composite. The GCD tests exhibit a high specific capacity and exceptional rate capability. Notably, the composite demonstrates a significantly higher specific capacity compared to individual Ni-MOF and rGO materials. The possible explanations for this improvement are improved ion transfer and enhanced surface area for ion adsorption due to compositization. Additionally, we employed electrochemical impedance spectroscopy (EIS) to gain insights into the dynamics of the composite's charge transfer and ion transport mechanism. The EIS analysis revealed low charge transfer resistance, indicating efficient charge storage and transport within the Ni-MOF/rGO composite.