Nanostructured conducting polypyrrole film prepared by chemical vapor deposition on the interdigital electrodes at room temperature under atmospheric condition and its application as gas sensor

摘要

In this work, the electrical conductive polymer is formed by vapor phase polymerization of pyrrole on the copper interdigital electrodes (Cu-IDEs) in the presence of Fe(III) as an oxidant at room temperature under atmospheric condition. Electrical resistance of IDEs covered with polypyrrole (PPy) layer was investigated and the relationship between the normalized electrical resistances (R - R (0)/R (0)), experimental conditions of vapor-phase coating (amount of oxidant and time coating) and response behavior of sensors to the volatile organic compounds were studied. The results showed that the pattern of response and selectivity of the sensor is affected by vapor phase polymerization conditions. The prepared PPy gas sensors were used at different conditions for detection and measurement of volatile organic compounds in the gas phase. The PPy gas sensors had demonstrated fast response time (< 1 s). Morphological study of the PPy coated layer by scanning electron microscope (SEM) showed that the conducting polymer prepared with nanotube shape. One of the sensors showed selective response toward of n-butylamine (PPy7) with the detection limit of 1 A mu g and linear range of 2-74 A mu g. The PPy7 gas sensor was used to measure n-butylamine in well water sample. Disperse liquid-liquid microextraction (DLLME) method was used for extraction and pre-concentration of n-butylamine from aqueous solutions. The extraction recovery of the proposed method was founded 93-105 %.