Preparation and Electrochromic Properties of Mesoporous WO₃ Film

Abstract

The WO3 film was prepared by dip coating method with WCl6 as the soure of tungsten and P123 as the structure-directing agent. The crystalline phase and microstructure of the film were characterized through XRD and TEM techniques, respectively. It was found the film annealed at 300°C for 4h mainly was amorphous WO3 with a little monoclinic WO3. The TEM micrographs revealed the film was partly ordered mesoporous and the mean pore diameter was about 5nm. The measurements of the cyclic voltammetry suggested that the WO3 film had a good electrochromic reversibility performance. The ratio of amount of charge intercalated and amount of charge deintercalated during the cyclic voltammetry, was over 99%. The film possessed a very short respond time which was only about 3.1s.

Nanoporous WO3 Gasochromic Films for Gas Sensing

“…The aforementioned cracks and pores increase the transmission of H and O while improving the heat resistance. On the basis of the TEM images shown in Figure c,d, after P123 removal many pores ranging from 10 to 16 nm in size remain, which are slightly larger than the 5–8 nm pores reported in the literature. − Compared to conventional high-temperature annealing, the WO 3 photocatalytic degradation method to remove the template does not produce pore collapse at high temperatures, so the pore size is slightly larger. Schuster et al conducted an in situ study on synthetic mesoporous materials employing small-angle X-ray scattering (SAXS) technology and found that only the ordered mesoporous structure could be observed after heating and curing for a certain period .…”

Scalable synthesis of improved nanocrystalline, mesoporous tungsten oxide films with exceptional electrochromic performance

“…Fig. 2 includes sol compositions previously reported in the literature for this chemistry [8,[35][36][37]. Though none of these studies reported on the sensitivity to sol composition, presumably there was some level of optimization and these points provided guidance for the present study.…”