Electrophoretic deposited WO3 nanorods for electrochromic application

Abstract

Among the transition metal oxides, tungsten oxide (WO3) remained the most promising candidate for electrochromic devices due to their good optical modulation, response time and wide band-gap semiconductor properties. The characterization of WO3 nanorods synthesized by hydrothermal process was studied. In this study, uniform Tungsten Oxide nanorods films were formed using electrophoretic deposition (EPD) technique. The EPD of WO3 nanorods under constant current, concentration, nanorod size, duration and pulse current were performed and the effects of various parameters on quality of film were investigated. It was discovered that smaller size nanorods (30 nm diameter) attained higher deposition mass and lower porosity as compared to 60 nm diameter nanorods. It was also found that the effectiveness of pulse current on mass deposition increases with shorter intervals and was able to achieve higher deposition mass and lower roughness as compared to constant current. The EPD prepared WO3 nanorods film produced excellent electrochromic properties such as fast switching time (< 6 s) and long lasting memory effects. The intercalated WO3 nanorods film showed higher absorption in IR spectrum and could propose applications on defense and smart windows technologies.