Hydrothermal synthesis and characterization of ruthenium oxide nanosheets using polymer additive for supercapacitor applications

Abstract

In the present work, Ruthenium oxide (RuO2) nanosheets were prepared by simple hydrothermal synthesis route in the presence and absence of PEG as surfactant. The synthesized RuO2 nanosheets act as electrode material and it was subjected to various physico-chemical properties to analyze the material suitability for the supercapacitor applications. The cubic structure, crystalline nature and purity of the material were confirmed by powder X-ray diffraction studies. The FTIR analysis confirms the presence of various functional groups in the RuO2 nanosheets. The optical absorbance wavelength was observed at 411 and 416 nm in the absence and presence of PEG surfactant. The shifting of wavelength reduces the energy band gap from bulk state of 2.45–2.26 eV due to the quantum confinement effect. The shape and surface morphology of the RuO2 nanosheets were determined by using FE–SEM analysis. The zeta potential analysis reveals the stability of the synthesized RuO2 nanosheets. The electrochemical properties of modified electrode RuO2 were investigated using various process such as cyclic voltammetry, specific capacitance, galvanostatic charge–discharge and electrochemical impedance spectroscopy in electrochemical workstation. Based on the electrochemical properties, the electrode material reveals the ideal capacitance behavior with high capacitance of 600 F/g at the sweep rate of 5 mV/s in 3 M KCL aqueous electrolyte solution. The remarkable electrochemical performance proves RuO2 as the promising material for storage applications.