Key points are not available for this paper at this time.
The electrochromic mechanism in amorphous tungsten oxide films is studied using Raman scattering measurements. The Raman spectra of as-deposited films show two strong peaks at 770 and 950 cm−1 due to vibrations of the W6+–O and W6+=O bonds, respectively, and a weaker peak at 220 cm−1 that we attribute to the W4+–O bonds. When lithium or hydrogen ions and electrons are inserted, extra Raman peaks due to W5+–O and W5+=O bonds appear at 330 and 450 cm−1, respectively. Comparison of the Raman spectra of sputtered isotopic a-W16O3−y and a-W18O3−y films confirms these assignments. We conclude that the as-deposited films contain mainly the W4+ and W6+ states, and the W5+ states are generated as a result of reduction of the W6+ states when lithium or hydrogen ions and electrons are inserted. We propose that the optical absorption in the colored films is caused by transitions between the W6+ and W5+, and W5+ and W4+ states.
Building similarity graph...
Analyzing shared references across papers
Loading...
Se-Hee Lee
Hyeonsik Cheong
Jiguang Zhang
Applied Physics Letters
National Renewable Energy Laboratory
Building similarity graph...
Analyzing shared references across papers
Loading...
Lee et al. (Mon,) studied this question.
www.synapsesocial.com/papers/6a0081e24716aad0cc85b8e6 — DOI: https://doi.org/10.1063/1.123268