| Owing to the special performance of continuous and reverse photoelectric property which can be manually controlled, electrochromic film materials, which are paid attention to by the science and technology world, and studied actively, have been widely applied in many fields, especially in the electrochromic devices. The electrochromic materials system mainly includes cathode electrochromic materials, in which the representative is tungsten oxide (WO3), and anticathode ones, in which the representative is nickel oxide (NiOx), as well as some organic electrochromic materials. Among many electrochromic materials, WO3 is regarded as one of the most potential materials because of its high coloration efficiency, strong reversibility, short transmission response time, long cycle life and lower cost. It is a pity that they are far from practical use, and it is important work that the material is put into practice. There are some ways to improve the films' electrochromic performances, for instance, optimizing process parameters and doping method are two effective ways.Usually, there are several preparation processes for electrochromic films such as sol-gel, vacuum-evaporation, chemical vapor deposition and sputtering deposition, in which the magnetron sputtering is the most optimal preparation process, for its merits of quick deposition velocity, low substrate temperature, good uniformity and adhesion, as well as controllable process parameters. However, there are relatively few reports on preparing WO3 films by magnetron sputtering.With pure tungsten and molybdenum targets, WOx and WOx:Mo films were deposited on ITO glass substrates by reactive magnetron sputtering and they were analyzed using spectrophotometer, XRD and STM. The effect of the process parameters on the electrochromic performances and the structure of WOx films were discussed. The changes of their optical properties and structure in the electrochromic reaction as well as the effect of the Mo-doping on the electrochromic performances and structure were studied. In addition, V2O5 films were deposited with pure vanadium target by the DC reactive magnetron sputtering and the process parameters were discussed.The research results show that the WOx and WOx:Mo films deposited by the reactive magnetron sputtering were amorphous; in electrochromic reaction their optical properties and structure would change and they behaved good electrochromic performances. The lower oxygen content enabled the films to have better electrochromic properties. It is helpful to improve the films' electrochromic properties with higher sputtering power and temperature in a range, and besides, the films tend to be crystal from amorphism in the higher sputtering temperature. The amorphism of Mo-doping WOx films, which have better electrochromic properties, tends to be stronger. It is rather complex to the effect of Mo-doping on electrochromic of WOx films, which is related to the doping mode and relative doping quantity. Even Mo-doping is helpful to greatly improve the electrochromic properties when the relative doping quantity is in the range of effective doping and around optimized value. V2O5 films deposited by DC reactive magnetron sputtering have rather better electrochromic properties. The oxygen content is the main process parameter affecting electrochromic properties, especilly the effect on the bleaching property of V2O5 films. Higher temperature contributes to induce to form crystallite, which is helpful to improve electrochromic properties. If the process parameters are optimized, V2O5 films' optical performances will meet the counterelectrode layer's optical demand in the electrochromic reaction.The performance parameters of the prepared WOx films show wide coloring range and quick transmission response time, but the open circuit memory ability and the cycle life need to be further improved. Mo-doping made the performance parameters of WOx films greatly improved, which shows its significance. The study of preparation for V2O5 films shows that the oxygen content... |
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