Preparation of WO3nanorods by a hydrothermal method for electrochromic device

Uniform WO 3 nanorods were prepared by a hydrothermal process, and the synthesis was accomplished by using NaCl as the capping agent and Na 2 WO 4 as the inorganic precursor. Scanning electron microscopy, X-ray diffractometer, transmission electron microscopy and UV–visible spectroscopy were used to characterize the morphology, phase, and nanostructure of the resulting nanorods. The effects of pH and the amount of NaCl capping agent on the morphology of the WO 3 nanorods were investigated. Uniform and regular aligned WO 3 nanorod films can be achieved by self-assembly in a drop coating process. Moreover, the electrochromic devices based on WO 3 nanorods display a deep blue color and have low transmittance (<2%) in the colored state, especially in the infrared range, which may provide a promising platform for energy-saving smart windows, and other electro-optical applications.