Preparation and electrochemical performance of TiO2-SnO2 doped RuO2 composite electrode for supercapacitors

TiO2-SnO2 doped RuO2 composite electrodes were prepared by wet balling mill plus precipitation processes. Composite materials were pre-annealed at different temperatures prior to test electrochemical performances, where 270 °C showed the most outstanding phase and morphology, which characterized by XRD and SEM, respectively. Morphology of composite showed small dispersed porous nanoparticles (average 43 nm). Meanwhile, TiO2-SnO2 doped RuO2 composite electrodes with different content were studied by using cyclic voltammetry, galvanostatic charge-discharge, electrochemical impedance spectrum as well as open circuit potential. Specific capacitance value of 571 F g−1 was registered for 35 wt.% TiO2-SnO2 doped composite electrode with good charge-discharge behavior. Impedance spectra curve displayed complete semicircles in high frequency region and nearly vertical lines in low frequency range. Open circuit potential of composite electrodes was remained stable at testing conditions. TiO2-SnO2 doped RuO2 electrodes can reduce loading of RuO2, which decrease cost.