Fabrication of sputtered titanium vanadium nitride (TiVN) thin films for micro-supercapacitors

Abstract

In the present work, we have demonstrated the micro-supercapacitor behavior of titanium vanadium nitride thin films fabricated on stainless steel substrates by a pulsed DC magnetron sputtering technique. The microstructural characterization from X-ray diffraction (XRD) reveals the FCC structure of TiVN thin films with a preferred (200) orientation. A faceted morphology with square-edge shaped dense grains of the thin films is observed from field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) images. Ion scattering spectroscopy (ISS) and X-ray photoelectron spectroscopy (XPS) was used to determine the surface compositions and confirmed the absence of impurities. The specific capacitance (Csp) of the electrode material was evaluated by cyclic voltammetry (CV). Galvanostatic charge–discharge (CD) test and the electrochemical impedance spectroscopy (EIS) measurements were also performed. The electrochemical result of fabricated TiVN displays a supercapacitive behavior. A maximum Csp of 69 F/g (volumetric capacitance of 155.94 F/cm3) is obtained from both CV and CD studies. The experimental results reveal that the sputtered TiVN thin films area promising electrode material for electrochemical micro-supercapacitors.