Conductive Polyaniline-tin Oxide Nanocomposites For Ammonia Sensor

Polymer Nanotech Laboratory, Department of Physics, RTM Nagpur University, Nagpur 440033, India

Adv. Mater. Lett., 2012, Current Issue, 3 (5), pp 393-398

DOI: 10.5185/amlett.2012.6361

Publication Date (Web): Sep 16, 2012

Copyright © IAAM-VBRI Press

E-mail: sbkondawar@yahoo.co.in

Abstract

Tin oxide (SnO₂) nanoparticles have been synthesized by simple route of sol-gel method. Polyaniline-tin oxide (PANI/SnO₂) nanocomposite (sample A) was prepared by an in-situ polymerization of aniline in the presence of as-synthesized SnO₂ nanoparticles. Similarly, tin oxide-intercalated polyaniline nanocomposite (sample B) was prepared using tin chloride (SnCl₄.5H₂O) as precursor during polymerization of aniline. Morphology and structure of both the nanocomposites have been studied using XRD pattern, FTIR spectra and SEM images which reveals that SnO₂ was uniformly mixed within the PANI matrix. In this paper we report the comparison of polyaniline-tin oxide (PANI/SnO₂) nanocomposites sample A and B for the response to ammonia. A laboratory set up for sensing ammonia has been built up using four probe resistivity unit and the response of the prepared PANI/SnO₂ nanocomposites to ammonia vapour for different concentration (5, 10, and 15%) was tested. PANI/SnO₂ nanocomposites were found to be good materials for NH₃ detection even at room temperature as compared to that of pure SnO₂. By comparing the response of sample A and B to the ammonia vapour, the sample A was found to be more sensitive than sample B due to highly porosity and surface activity of sample A. The results were reproducible and checked by repeating observations. Synthesis route for the preparation of PANI/SnO₂ nanocomposites is an important factor while selecting the materials for ammonia sensing.

Keywords

Conducting polymers, polyaniline, tin oxide, nanocomposites, ammonia sensor.