Porous Single-wall Carbon Nanotube Films Formed By In Situ Arc-discharge Deposition For Gas Sensors Application

摘要

A gas sensor structure for high performance is developed based on a porous film structure of single-wall carbon nanotubes (SWNTs). The SWNTs are directly deposited on the substrate in situ in the arc-discharge chamber, and the steric hindrance during the deposition permits high porosity in the carbon nanotube thin film. The SWNTs are characterized and their capacities of sensing NO and NH_3 gases are investigated down to 2 ppm-level concentration at room and elevated temperatures. The effect of sensor porosity is examined and compared with that of a nonporous sensor structure. The response and recovery behaviors are examined with temperature variations.