Co3O4/rGO based nanocomposite architectures as electrodes for advanced energy storage and their pseudocapacitive attributes

Abstract

In response to escalating global challenges in energy storage, this study embarked on captivating exploration of electrochemically proficient Co₃O₄ composites, seamlessly integrated with varying concentrations of reduced graphene oxide (5 %, 10 %, and 15 %). Using a single-step hydrothermal method, Co₃O₄ was synthesized, followed by a solvothermal process to produce Co₃O₄/rGO composites. These composites were then applied to Nickel Foam to fabricate electrodes. The structural properties of these novel Co₃O₄/rGO/NF electrodes were analyzed using X-ray Diffractometer, which confirmed the distinctive crystalline structure of Co₃O₄ and indicated no phase transformation after the introduction of rGO. Morphological analysis through a Field Emission Electron Microscope and Transmission Electron Microscope revealed layered structures and increasing porosity correlated with higher rGO concentrations. Electrochemical performance was rigorously tested through cyclic voltammetry, which verified the pseudocapacitive attributes of the samples. Additionally, galvanostatic charge-discharge studies highlighted that the electrode containing 15 % rGO demonstrated highest (C_s = 1360 Fg⁻¹) at 1.7 Ag⁻¹, with 86 % of cyclic retention after 5000 cycles. Electrochemical impedance spectroscopy further demonstrated superior conductivity, underscoring the potential of these electrodes'for supercapacitor applications.