Pulse electrodeposited RuO₂ electrodes for high-performance supercapacitor applications

The present work addresses high-performance Ruthenium Oxide (RuO₂) electrodes prepared by using a simple pulse electrodeposition method. For the comparison purpose, two different precursors, namely, ruthenium (III) nitrosyl sulphate (RuNS) and ruthenium trichloride (RuCl₃), were used in this study. The coatings were subjected to material characterisation such as Field Emission Scanning Electron Microscopy and Energy-Dispersive X-ray Spectroscopy, X-ray diffraction and Transmission electron microscopy as well as electrochemical characterisation such as Cyclic Voltammetry, Electrochemical Impedance Spectroscopy and charge/discharge. The RuNS–RuO₂ coating exhibited excellent specific capacitance (1724 F/g at 5 A/g) with a remarkable rate capability. This value is significantly higher (52%) than the value obtained for RuCl₃–RuO₂ electrode material at 5 A/g. The findings provide valuable information on the potential use of RuNS as a precursor for synthesising RuO₂ and pulse electrodeposition process to produce electrodes for supercapacitors.