Role of Conducting Polymer as Chemical Sensor

Abstract

Chemical sensors have an important role in monitoring the environment, providing

information on industrial processes and manufacturing, leak detection, detection of explosive,

combustible and flammable gases, quality control of food and beverages etc. Conducting

polymers are used as sensitive layers in chemical micro-sensors. Conducting polymers such

as polypyrrole (PPy), polyaniline(PANI),polythiophene, polythiophene and their derivatives

are considered as prominent new materials for chemical sensors because of their ability to

form good basis for chemical sensors either as a sensing element or as matrices to immobilise

specific reagents. Few of the advantages with conducting polymers as sensing materials are

high performance, light in weight, low cost, flexible, fast response and simple fabrication

process, control ability of electrical conductivity and exhibit highly reversible redox

behaviour with a distinguishable chemical memory. Amongst all the conducting polymers,

PANI is especially attractive due to its ease of synthesis, less expensive, environmental

stability, unique conduction mechanism, relatively stable electrical conductivity and simple

doping/dedoping chemistry. Conducting polyaniline has been used as a sensing material for

different vapours like methanol, ethanol, acetone, benzene and as humidity sensors also. This

paper explores the potential of using conducting polymers as chemical sensors highlighting

on the use of PANI.