Electrochromic properties of cesium tungstate with pyrochlore structure

Abstract

The crystal structure of pyrochlore (Cs 2O') 0.44W 2O 6 was determined by analyzing the powder X-ray diffraction pattern. (Cs 2O') 0.44W 2O 6 belongs to Fd3m space group with W at 16c, O at 48f, Cs at 16d, and O' at 8b sites in the unit cell. The crystal structure of the films evaporated from (Cs 2O') 0.44W 2O 6 powder was found to be the same as that of the source material. The films turned a gray-blue color after hydrogen ion injection. The chemical diffusion coefficient D≈ 7 × 10 −9 cm 2 s -1 for hydrogen in H y(Cs 2O) 0.44W 2O 6 was found to be independent of hydrogen concentration in the range from y = 0.05 to y = 0.5.