With the aim to enhance the electrochromic (EC) efficiency and electrochemical stability of electrochromic devices (ECD), mixed nanostructured TiO2/WO3films were prepared by an electrochemical deposition method with the purpose of adding WO3nanoparticles to porous nanocrystalline doctor-blade TiO2(nc-TiO2) films. The results of the characterization of electrochromic properties in 1 M LiClO4+ propylene carbonate (LiClO4+ PC) of both the nc-TiO2/F-doped tin oxide (FTO) and WO3/TiO2/FTO configurations showed the reversible coloration and bleaching of the ECDs. The response time of the ECD coloration of WO3/TiO2/FTO was found to be as small as 2 sec, and its coloration efficiency (CE) as high as 35.7 cm2× C−1. By inserting WO3nanoparticles into the porous TiO2structures, WO3/TiO2heterojunctions were formed in the films, consequently enabling both the CE and electrochemical stability of the working electrodes to be considerably enhanced. Since a large-area WO3/TiO2can be prepared by the doctor-blade technique followed by the electrochemical deposition process, mixed nanostructured Ti-W oxides electrodes constitute a good candidate for smart window applications, taking advantage of the excellent coloration and stability properties as well as the simple and economical fabrication process involved.

Polyaniline (PANI) onto indium-doped tin-oxide (ITO)-coated glass samples were prepared by electroopolymerization in 0.5 M H 2 SO 4 solution. Structure and morphology characterization of the PANI films demonstrated that the films were grown onto ITO substrates in the form of polycrystalline microbelts separated by micropores. By analysing the UV-Vis absorption spectra of the PANI films, the energy bandgap was found to be approximately 2.75 eV. The PANI/ITO films exhibited a good reversible electrochromic display (ECD) performance when cycled in 0.1 M LiClO 4 + pro-pylene carbonate. The response time of the ECD coloration was found to be as small as 15 s and the coloration efficiency was found to be 8.85 cm 2 × C −1 . After 100 cycles of the ECD performance, the cyclic voltammetry curve of the working electrode maintained unchanged. This demonstrates that the electropolymerized PANI films can be served as a good candidate for ECD applications, taking advantage of their excellent properties in terms of chemical stability.

Using doctor-blade technique, followed by electrochemical deposition, nanocomposite WO\(_{3}\)-TiO\(_{2}\) films were prepared. Structure, morphology and composition ratio of the nanocomposite films were characterized by a comprehensive analyzing the SEM, EDX, XRD and Raman scattering results. The reversible coloration and bleaching of TiO\(_{2}\)/ITO and WO\(_{3}\)-TiO\(_{2}\)/ITO electrodes were demonstrated. The ECD coloration efficiency of WO\(_{3}\)-TiO\(_{2}\)/ITO was found to be much larger (55.1 cm\(^{2}\times \text{C}^{ - 1})\) than that of TiO\(_{2}\)/ITO (34.3 cm\(^{2}\times \text{C}^{ - 1})\). The resulting nanostructured composites enables the coloration efficiency of the WO\(_{3}\)-TiO\(_{2}\) film to be considerably improved. The results suggest a potential application of the nanocomposites of two electrochromic oxides in large-area energy-efficiency (or smart) windows.