Silver Nanoparticles Embedded on Reduced Graphene Oxide@Copper Oxide Nanocomposite for High Performance Supercapacitor Applications

• Main Authors: Akhalakur Rahman Ansari, Sajid Ali Ansari, Nazish Parveen, Mohammad Omaish Ansari, Zurina Osman
• Format: Article
• Language: English
• Published: MDPI AG 2021-09-01
• Series: Materials
• Subjects: reduced graphene oxide; metal; metal oxide; electrochemical devices
• Online Access: https://www.mdpi.com/1996-1944/14/17/5032

In this work, silver (Ag) decorated reduced graphene oxide (rGO) coated with ultrafine CuO nanosheets (Ag-rGO@CuO) was prepared by the combination of a microwave-assisted hydrothermal route and a chemical methodology. The prepared Ag-rGO@CuO was characterized for its morphological features by field emission scanning electron microscopy and transmission electron microscopy while the structural characterization was performed by X-ray diffraction and Raman spectroscopy. Energy-dispersive X-ray analysis was undertaken to confirm the elemental composition. The electrochemical performance of prepared samples was studied by cyclic voltammetry and galvanostatic charge-discharge in a 2M KOH electrolyte solution. The CuO nanosheets provided excellent electrical conductivity and the rGO sheets provided a large surface area with good mesoporosity that increases electron and ion mobility during the redox process. Furthermore, the highly conductive Ag nanoparticles upon the rGO@CuO surface further enhanced electrochemical performance by providing extra channels for charge conduction. The ternary Ag-rGO@CuO nanocomposite shows a very high specific capacitance of 612.5 to 210 Fg⁻¹ compared against rGO@CuO which has a specific capacitance of 375 to 87.5 Fg⁻¹ and the CuO nanosheets with a specific capacitance of 113.75 to 87.5 Fg⁻¹ at current densities 0.5 and 7 Ag⁻¹, respectively.