The electrode materials SnO<sub>2</sub>, RuO<sub>2</sub> and (Sn-Ru)O<sub>2</sub> were synthesized through precipitation method from SnCl<sub>2</sub>·2H<sub>2</sub>O and RuCl<sub>2</sub>·2H<sub>2</sub>O solutions. The obtained nano-sized pristine products were characterized using X-ray diffractometry, Scanning Electron Microscopy (SEM), differential scanning calorimetry (DSC)-thermogravimetric analysis (TGA) and cyclic voltammetry (CV). The Debye–Scherrer formula was used to estimate the average size of the nanoparticles SnO<sub>2</sub> (36 nm), RuO<sub>2</sub>(24 nm), and (Sn-Ru)O<sub>2</sub> (19 nm). Electrochemical studies were carried out to examine the capacitance of SnO<sub>2</sub>, RuO<sub>2</sub>, (Sn-Ru)O<sub>2</sub> electrodes in 0.5 M H<sub>2</sub>SO<sub>4</sub> at various scan rates. The estimated electrode capacitance was de-termined to decrease with an increase of scan rate.
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