Metal-Phthalocyanine Functionalized CNTs Sensor for Chloroform Series

Abstract

In this paper, We report fabrication of sensors from multiwalled carbon nanotube (MWCNT) functionalized with metal-phthalocyanines (M-Pc or Cu-Phs). We made very sensitive ans selective sensor for Chloroform. We had characterized the material using FTIR and TEM techniques. We inferred that the metal-Pc form nanoclusters around the surface of f-MWNTs and the sensors prepared from these materials show resistivity in the kilo-ohm range. Our sensors show sensing capability of 100 ppm and the response as well as recovery times of few seconds. We observed interesting behaviour of the sensors made from M-Pc on exposure to chloroform (CHCl3) vapours while for many other vopours like carbon tetra chloride (CCl4), dichloromethane (CH2Cl2), clorine water (Cl2) showed opposite results after the exposure on these sensors. We shall discuss the differences in the response and recovery time, and mechanism of sensing for chloroform and other vapours. The present work proposes the MPc/ f-MWCNT nanocomposite based pair sensors for selective detection of chloroform at room temperature. A combination of sensors made from composites of cobalt-phthalocyanine (Co-Pc) and copper-phthalocyanine (Cu-Pc) with f-MWCNT. The responses of these composites for different organic vapors were evaluated by monitoring the change in the resistance of thin film of composite when exposed to gases. It was observed that the CNT/MPcs showed the higher and selective response. Sensor response toward chloroform was tested, and the result shows that MPc/ f-MWCNT array has the good response and high reproducibility at ambient condition.