H2 sensing properties of diode-type gas sensors fabricated with Ti- and/or Nb-based materials

SENSORS AND ACTUATORS B-CHEMICAL

卷:142

Article

Hyodo, Takeo¹  Shibata, Hiroki¹  Shimizu, Yasuhiro²  Egashira, Makoto² 

[1] Nagasaki Univ, Grad Sch Sci & Technol, Nagasaki 8528521, Japan

[2] Nagasaki Univ, Fac Engn, Dept Mat Sci & Engn, Nagasaki 8528521, Japan

关键词: Gas sensor;    Hydrogen;    Titania;    Niobium oxide;    Palladium;   

DOI  :  10.1016/j.snb.2009.07.058

来源: Elsevier

【 摘 要 】

A thermally oxidized TiO(2) or Nb(2)O(5) film equipped with a top Pd film electrode and a bottom Ti or Nb plate electrode (Pd/MO(n)/M, MO: oxide film, M: metal plate, n: annealing temperature (degrees C)) has been investigated as a diode-type H(2) sensor under air or N(2) atmosphere. Pd/TiO(2)(n)/Ti sensors showed relatively poor H(2) sensing properties in air, in comparison with Pd/anodic-TiO(2)(n)/Ti sensors constructed with an anodized TiO(2) film equipped with a top Pd film electrode and a bottom Ti plate electrode, which were reported in our previous studies. On the other hand, Pd/Nb(2)O(5)(n)/Nb sensors showed relatively larger H(2) response with fast response and recovery speeds than Pd/TiO(2)(n)/Ti sensors in air under high forward bias conditions. A Pd/Nb(2)O(5)(450)/Ti sensor, which was fabricated by radio-frequency magnetron sputtering of Nb metal on a Ti substrate followed by thermal oxidation at 450 degrees C, showed the largest H(2) response and relatively fast response and recovery speeds in air, among the sensors tested. In addition, H(2) response of the Pd/Nb(2)O(5)(450)/Ti sensor in air was much lower than that in N(2), but the logarithm of H(2) response was almost proportional to the logarithm of H(2) concentration in a wide range of H(2) concentration (10-8000 ppm) in air, and the H(2) sensitivity in air was much higher than that in N(2). (c) 2009 Elsevier B.V. All rights reserved.

【 授权许可】

Free