Science in China Series E: Technological Sciences

, Volume 50, Issue 4, pp 510–515

Capacitive humidity sensing properties of carbon nanotubes grown on silicon nanoporous pillar array

  • Jiang WeiFen 
  • Xiao ShunHua 
  • Zhang HuanYun 
  • Dong YongFen 
  • Li XinJian 


Multi-walled carbon nanotubes (CNTs) were grown on silicon nanoporous pillar array (Si-NPA) by thermal chemical vapor deposition method, and the structural and capacitive humidity sensing properties of CNT/Si-NPA were studied. It was found that with the relative humidity (RH) changing from 11% to 95%, a device response of ∼480% was achieved at the frequency of 50000 Hz, and a linear device response curve could be obtained by adopting longitudinal logarithmic coordinate. The response/recovery times were measured to be ∼20 s and ∼10 s, respectively, which indicated a rather fast response/recovery rate. The adsorption-desorption dynamic cycle experiments demonstrated the high measurement reproducibility of CNT/Si-NPA sensors. These excellent performances were attributed to the unique surface structure, morphology and chemical inertness of CNT/Si-NPA.


capacitive humidity sensor carbon nanotubes (CNTs) silicon nanoporous pillar array (Si-NPA) CNT/Si-NPA 


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Copyright information

© Science in China Press 2007

Authors and Affiliations

  • Jiang WeiFen 
    • 1
  • Xiao ShunHua 
    • 1
  • Zhang HuanYun 
    • 1
  • Dong YongFen 
    • 1
  • Li XinJian 
    • 1
  1. 1.Department of Physics and Laboratory of Materials PhysicsZhengzhou UniversityZhengzhouChina

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