Effect of Plasma Treatment on Multi-Walled Carbon Nanotubes for the Detection of H<sub>2</sub>S and SO<sub>2</sub>

• Main Authors: Xiaoxing Zhang, Bing Yang, Xiaojing Wang, Chenchen Luo
• Format: Article
• Language: English
• Published: MDPI AG 2012-07-01
• Series: Sensors
• Subjects: carbon nanotubes; gas sensor; modification
• Online Access: http://www.mdpi.com/1424-8220/12/7/9375

H<sub>2</sub>S and SO<sub>2</sub> are important characteristic gases of partial discharge (PD) generated by latent insulated defects in gas insulated switchgear (GIS). The detection of H<sub>2</sub>S and SO<sub>2</sub> is of great significance in the diagnosis and assessment of the operating status of GIS. In this paper, we perform experiments on the gas sensitivity of unmodified multi-walled carbon nanotubes (MWNTs) and those modified by atmospheric pressure dielectric barrier discharge (DBD) air plasma at different times (30, 60 and 120 s) for H<sub>2</sub>S and SO<sub>2</sub>, respectively. The results show that the sensitivity and response time of modified MWNTs to H<sub>2</sub>S are both improved, whereas the opposite effects are observed for SO<sub>2</sub>. The modified MWNTs have almost zero sensitivity to SO<sub>2</sub>. Thus, the MWNTs modified by atmospheric pressure DBD air plasma present good selectivity to H<sub>2</sub>S, and have great potential in H<sub>2</sub>S detection.