%0 Journal Article
%T Electrochemical Response for Spherical and Rod Shaped WO3 Nanoparticles
%A Sangeeta Adhikari
%A Debasish Sarkar
%J ISRN Nanotechnology
%D 2013
%R 10.1155/2013/279398
%X A rapid and new technique describes synthesis technique of spherical and rod shaped tungsten trioxide (WO3) nanoparticles with similar band gap at visible wavelength. Acid catalyzed exothermic reaction and structure directing reagent follows the formation of two different morphologies and monoclinic WO3 phase. Rod shaped WO3 nanoparticle coated ITO glass electrode exhibits high current density at identical low voltage and scan rate due to its better adherence and coating uniformity in comparison with spherical nanoparticles. WO3-ITO electrode alters to blue tungsten bronze in color at low voltage, and further the color restores after removing the same applied voltage. 1. Introduction In recent years, different morphology nanostructured materials have stimulated great interest due to their importance in basic scientific research and technological applications [1, 2]. Tungsten trioxide (WO3), an important n-type semiconductor, has received much attention in the past few decades for it¡¯s potential application in fabricating the miniature electrochromic and photochromic devices, gas sensors, and solar energy devices and also its usage as photoanode to generate hydrogen by photocatalytic splitting of water [3, 4]. The importance demands control over the dimension, size, and crystal structure of this class of particles for higher technology applications. Apart from being a promising electrochromic material, a great deal of effort has been made for improving the performance of WO3 films by several researchers. Thus, it is essential to control the morphology and also the surface coating over transparent coating oxide glass substrate [5]. Mostly, fabrication of WO3 films has been prepared by dip or spun coating of peroxopolytungstic acid on the Indium doped Tin Oxide (ITO) glass substrate and subsequent firing at optimum temperature [6, 7]. Leftheriotis et al. prepared sol-gel derived highly porous thick and opaque WO3 films. These films exhibited a similar reversible electrochromic property for 1st and 1000th cycle of cyclic voltammograms in 1£¿M LiClO4 with 0.2£¿mA/cm2 as current density [8]. Comparison of the electrochromic performance for orthorhombic rod and platelet type hydrated WO3 was investigated by Wei and Shen. Poly vinyl alcohol (PVA-124) and glacial acetic acid were used as structure directing agent and stabilizer for the preparation of single crystalline WO3 H2O nanorods, which exhibited highest current density of 40£¿mA/cm2 with fast response time and improved redox performance [5]. Peroxotungstic acid was used for the deposition of WO3.nH2O film on
%U http://www.hindawi.com/journals/isrn.nanotechnology/2013/279398/