Crystal Structure, Morphology, Optical and Super-Capacitor Properties of Srx: α-Sb2O4 Nanostructures

Mixed orthorhombic Sr-x doped alpha-Sb2O4 (x=2,4,8 and 10 wt. %) nanostructures (NS) were successfully synthesized by simple chemical precipitation method. Crystal structure, morphologies and microstructures of the as-synthesized Sr-x: alpha-Sb2O4 NS were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. XRD displayed that the NS were extensively crystalized and crystallite size increases with increase in the concentration of Sr2+ ions. SEM revealed spherical like morphologies and grain size varies between similar to 88 nm to 110 nm. Red shift in the optical absorptivity and increase in the optical band gap (Eg) displayed in UV-visible spectra as the Sr concentration increases in alpha-Sb2O4 NS. In Fourier transform infrared spectra (FT-IR), intensity of the characteristic peak Sb-OH gradually increases as Sr2+ dopant concentration increases in NS. Electrochemical performances of Sr-x: alpha-Sb2O4 (x =10 wt. %) NS exhibited specific capacitance of 890 F/g at a current density of 1 A/g in 6 M KOH solution. Sr-x: alpha-Sb2O4 NS showed cyclic retention of 88.95 %, long term cyclic stability up to 1000 cycles and excellent repeatability and reproducibility. Sr-x:alpha-Sb2O4 NS act as a promising electrode material for super capacitor and can be used in high energy storage device applications.