Sensing characteristics of nano-network structure of polypyrrole for volatile organic compounds (VOCs) gases

Nanowires of conducting polypyrrole (PPy) were synthesized by chemical polymerization methode. The 0.18 mol of pyrrole (Py) as monomer, 0.18 mol of dodecyl-benzene sulfonic acid (DBSA) as dopant and 0.26 mol of anhydrous iron(lll) tri chloride (FeCl₃) as oxidant were mixed and stirred in 200 ml of distilled water at 0degC. The reaction was carried out for three different times (6 h, 24 h, 40 h) and reaction rate was 200 rpm. The morphology of PPy was evaluated by field emission scanning electron microscopy (FE-SEM). It was found that the morphology of nanowire PPy was affected by reaction time and aggregation rate. When the polymerization time was getting longer, nanowire structure was appeared clearly. The sensitivities of nanowire PPy were investigated with volatile organic compounds (VOCs).