Titanium Oxynitride Thin Film Supercapacitor Decorated with Ruthenium Oxide Nanoparticles

Supercapacitors have attracted a lot of attention as energy storage devices for high power applications such as digital mobile phone device power sources, memory backup devices, and hybrid electric vehicle power sources. Ruthenium oxide has been studied as one of the best electrode material for supercapacitors, owing to its advantages of a wide potential window of highly reversible redox reactions, remarkably high specific capacitance, and a very long cycle life.

In this work, we demonstrate the synthesis of pulsed laser deposited titanium oxynitride thin film decorated with RuO₂ nanoparticles as an attractive class of materials for electrochemical charge storage. X ray diffraction analysis of the nanostructure shows that the sharpness and intensity of the TiNO (111) peak decreases with addition of the RuO₂ nanoparticles compared to undecorated TiNO film. The scanning electron microscopy and the energy dispersive X-ray spectroscopy analyses of the RuO₂-np/TiNO sample indicate that the RuO₂ nanoparticles are uniformly dispersed on TiNO support with an average particle size of The X-ray photoelectron spectroscopy survey scan analysis confirms the presence of Ru with the Ru 3d peak at a binding energy of 281.8 eV and elemental percentage loading of 1.21%. The cyclic voltammetry plot has shown that the decorated-TiNO electrode occupies a larger area which is proportional to the charged stored on the electrode. The specific capacitance values calculated from the galvanostatic discharge curves further reveals that the decorated-TiNO showed significant increase in the capacitance value (113 mF.cm^-2) compared to the undercoated-TiNO counterpart (43 mF.cm^-2). This enhancement in the capacitance is related to the synergistic effects of RuO₂ decoration, oxygen doping, and the unique structural properties of the fabricated thin film.