Nano-composite sensors composed of single-walled carbon nanotubes and polyaniline for the detection of a nerve agent simulant gas

This paper reports the response behavior at room temperature of a composite sensor composed of single-walled nanotubes (SWCNTs) and polyaniline, to the nerve agent simulant gas dimethyl-methyl-phosphonate (DMMP), a typical Sarin simulant. The SWCNT-polyaniline composite was synthesized to obtain high-quality composites with good uniformity. The composites were drop-cast onto an oxidized Si substrate patterned with Pd electrodes. SWCNT-polyaniline composite sensors exhibited clear, sharp response curves for DMMP in air at room temperature, even at minuscule concentrations. The response and response time were 27.1% and 5.5 s, respectively, at 10 ppm DMMP, representing a significant improvement over the pure SWCNT network sensors previously reported. These results indicate that SWCNT-polyaniline composite sensors can be ideal DMMP sensors, operating at room temperature with high response, fast response time, and excellent reproducibility.