Room temperature carbon monoxide gas sensor based on Au/polyaniline nanocomposite

In the present work, the effect of gold (Au) nanoparticles (NPs) on room temperature carbon monoxide (CO) gas sensing performance of polyaniline (PANI) gas sensor at room temperature was studied. The emeraldine salt polyaniline nanofibers were synthesized by a chemical polymerization method. Then, Au/PANI nanocomposites were synthesized by the direct mixing of prepared PANI nanofibers and different concentrations of Au NPs. The crystal structure, morphology, and composition of the prepared materials were characterized by means of X-ray diffraction (XRD), UV–vis spectroscopy, Fourier-transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectrometer (EDX) and transmission electron microscope (TEM). TEM images show that the Au NPs successfully decorated the surface of PANI nanofibers. The gas sensing performance of all sensors was investigated toward various concentrations of CO gas ranging from 200 to 6000 ppm at room temperature. The fabricated 2.5% Au/PANI sensor exhibited high sensitivity, low detection limit (33 ppm), fast response time (200 s) and good selectivity. Thus, the proposed Au/PANI sensor might give a promise for high-performance room temperature CO-sensing applications

Keywords:

Au/PANI nanocomposite , Carbon monoxide , Room temperature , Gas sensor