Study On The Preparation And Properties Sensitive To Hydrogen Of Tungsten Oxide Films

Tungsten trioxide film is one kind of the important functional material. It is studied and applied extensively because of its electrochromic property, gasochromic property, photochromic property, electrochemistry, etc. This article makes the elaboration to the structure of tungsten trioxide molecular and color changed mechanism .Because of it is not sensitive to hydrogen at normal temperature, so tungsten trioxide with doped Pd or Pt as catalyst to improving its hydrogen response was adopted.The Pt or Pd sputtered tungsten trioxide sol-gel film by DC magnetron sputtering method has better property as loosen holes which have fast hydrogen response ionized by Pt or Pd. The film has excellent hydrogen absorbing property and the method is preferred for the sensor to distinguish hydrogen.materials, instrumentation, technological process were introduced in detail.And the optical property and surface structure of the films was also studied.Secondly, the Pt or Pd as catalyst were sputtered tungsten trioxide sol-gel film by DC magnetron sputtering.And the theory, technological process and the optimized preparation parameters of DC magnetron sputtering were presented in detail.At the same time , the films were tested and the importance factors which affect the properties of the films were analyzed particularly.The tungsten trioxide films prepared by sol-gel and the films with catalyst sputtered by DC magnetron sputtering were characterized by XRD, STM, FT-IR, UV-VIS and so on. As the result of XRD, the temperature from amorphous to crystal of tungsten trioxide sol-gel films with catalyst is higher than sol-gel films'.As results of STM, both Pt sputtered tungsten trioxide films and Pt sputtered tungsten trioxide sol-gel films there is distinct and out-of-order parallel line structure on the surface of amorphous. Molecules of the sample tend to tetrahedron and the former has more planarer structure. Atoms of the film by DC reactive magnetron with Pt sputtered tend to plane ordinal structure. Molecules of the the film by sol-gel with Pt sputtered tend to be surface center structure as WO6. As results of transmission, the film with Pt catalyst has better hydrogen response than the film with Pd catalyst.As results of FT-IR, the characteristic oscillation of the tungsten oxide sol-gel film with Pd catalyst is more distinct with the higher temperature at the wave band 400~1000nm.The study of tungsten trioxide provided some foundation for developing the hydrogen sensitive optical fibersensor.