Synthesize of polyaniline–multi walled carbon nanotubes composite on the glass and silicon substrates and methane gas sensing behavior of them at room temperature

In this study, fabrication of methane gas sensor using composites of multi-walled carbon nanotubes (MWCNT) and polyaniline (PANI) on glass and silicon substrates is reported. In this respect, 8 wt% of purified MWCNT by acid washing procedure, was combined with PANI by solution mixing method. The MWCNT–PANI composite was deposited on the surface of glass and Si substrates using spin coating technique. The methane gas sensing of composite films were evaluated by measuring the change of electrical resistance in the presence of methane gas at room temperature. It is observed that the MWCNT–PANI film on the Si substrate shows a higher sensitivity to methane gas in comparison to pure PANI on the glass substrate. The characterization of samples has also been investigated by Fourier transform infrared, transmission electron microscopy and scanning electron microscopy analyses.