PORPHYRIN FUNCTIONALIZED CARBON NANOTUBE THIN FILMS AS SENSOR FOR DETECTION OF NITROGEN DIOXIDE

摘要

The present invention relates to a process for the preparation of functionalized multi-walled carbon nanotubes by porphyrins and their use as highly selective sensor for detection of nitrogen dioxide vapors. The invention provides a process in which multiwall carbon nanotubes (CNT) are first functionalized using corona electrostatic discharge technique, and then a composite consisting of these functionalized CNT"s and porphyrins is prepared via non-covalent methods like blending technique resulting in the porphyrin functionalized Ac-CNT"s. The present invention sensors have resistivity in the kilo-ohm range with response time of few seconds. This technique for fabrication of sensors is simple, fast, and low cost and does not require any expensive or specialized equipment. The thin films can be formed on almost any substrate including glass, plastic and irregularly shaped substrates and is very cost effective. These properties make the present invention sensors very attractive for commercial applications for detection of NO2 vapors in exhaust gas from a combustion furnace, automobile engine, coal mines, and in the detection of NO2 based explosive devices.