Madridge J Anal Sci Instrum.
ISSN: 2638-1532
21 Volume 2 • Issue 1 • 1000105
Madridge
Journal of Analytical Sciences and
Instrumentation
Research Article Open Access
Effect of Solvent Polarity on Fluoroscence Spectra
of Camphor Sulphonic Acid Doped Polyaniline
Lakshmidevi V
1
, Parvathi P
1
and Venkataraman A
1,2
*
1
Materials Chemistry Laboratory, Department of Materials Science, Gulbarga University, Kalaburagi- 585106, Karnataka, India
2Department of Chemistry, Gulbarga University, Kalaburagi- 585106, Karnataka, India
Article Info
*Corresponding author:
Venkataraman A
Department of Chemistry
Gulbarga University
kalaburagi-585106
Karnataka, India
Email: raman.dms@gmail.com
Received: January 9, 2017
Accepted: January 24, 2017
Published: January 27, 2017
Citation: Lakshmidevi V, Parvathi P,
Venkataraman A. Effect of Solvent Polarity on
Fluoroscence Spectra of Camphor Sulphonic
Acid Doped Polyaniline. Madridge J Anal Sci
Instrum. 2017; 2(1): 21-24.
doi: 10.18689/mjai-1000105
Copyright: © 2017 The Author(s). This work
is licensed under a Creative Commons
Attribution 4.0 International License, which
permits unrestricted use, distribution, and
reproduction in any medium, provided the
original work is properly cited.
Published by Madridge Publishers
Abstract
The Camphor sulphonic acid doped polyaniline (CSA-PANi)is synthesized by
chemical polymerization method and then characterized by using UV-Visible and FTIR.
The surface morphology is studied by SEM and AFM techniques. The degree of
crystallinity of PANiis studied by XRD and redox behaviour by cyclic voltametry. Thermal
stability of the doped polymer is investigated by TGA and DSC. The fluorescence
emission spectra of CSA-PANiare investigated in different solvents such as dimethyl
formamide(DMF), dimethyl sulphoxide (DMSO) and N-methyl-2-pyrrolidone (NMP).
The fluorescence intensity decreases with increase of solvent polarity. A fluorescence
study reveals that the nature (blue or red shift) and amount of the shifts of PANi depends
on the solvents used. The significance of present study evolves a trend in solvatochromic
shifts of PANi in different solvents.
Keywords: Conducting Polymer; PANi; Dipole Moment; Fluorescence; Stokes Shift;
Solvatochromic Shift.
Introduction
Conducting polymers were considered as the futuristic new materials that would
lead to the next generation of electronics and optoelectronics devices. Among all
conducting polymers PANi and its derivatives have attracted much attention worldwide
because of chemical stability, simple preparation and high conductivity, low ionization
potential, high electron affinity and the ability to be oxidized or reduced more
reversibly than conventional polymer [1-3]. PANi has extended π-electron
delocalization, which is responsible forfluorescence emission and it is a fluorescent
conjugated polymer. The photoluminescence of PANiemeraldine salt was reported by
Gong etal [4]. The extended conjugation also leads to intermolecular hydrogen bonds
between the amine and imine group of the adjacent chain and pi stacking. Hence the
polymer chain becomes rigid which induces insolubility and infusibility to the polymer
chain. The processability of PANi can be improved by using functionalized dopants
like CSA or DBSA which was first reported by Cao. et al [5]. The bulky dopants will
reduce the mutual aggregation by increasing the solubility of PANisalt in non-polar
and weakly polar solvent.
In recent years considerable effort has been made to design and to synthesize
functional molecule that could serve as sensitive sensors for the analytical detection of
chemically and biologically important ionic species. Fluorescence sensors have received
a considerable attention for their potential applications to biochemical and medical
analysis. The effect of solvents on spectral properties of molecules generally referred as
solvatochromism has been investigated [6]. The study of solvent effects on fluorophore
ISSN: 2638-1532