2023 Volume 64 Issue 9 Pages 2147-2150
Hydrogen adsorption in WO3 thin films is known to cause the change of color of the films. Due to its high sensitivity, chemical stability as well as biocompatibility, the WO3 offers itself as an efficient hydrogen sensor, especially for detection of hydrogen in humid environments. In this paper we report the preparation and characterization of WO3 electrochoromic thin films prepared on ITO substrates by thermal evaporation synthesis. These films show significant decreases in transparency from over 92% to as low as 2% at an applied bias of −0.7 V. Structure as well as the effect of annealing temperature on the structure and properties of the films are also studied. The changes of optical band gap and the role of hydrogen in coloration process are also discussed.
