ENHANCEMENT OF RAMAN SCATTERING, OPTICAL ABSORPTION AND ELECTRICAL PROPERTIES OF PEDOT: PSS THIN FILM USING BIOSYNTHESIZED GOLD-SILVER NANOPARTICLES

Abstract

Poly (3,4-ethylene dioxythiophene): poly (styrene sulfonate) (PEDOT: PSS) is a transparent and conducting polymer widely used in polymer photovoltaic cells, sensors, and organic light-emitting diodes (OLEDs). However, the application of the polymer is restricted due to its low optical absorption and electrical conductivity. Also, the negative environmental impact on our modern world because of the use of toxic chemicals to improve this polymer’s properties cannot be overlooked. In this research, the absorption and conductivity of the transparent PEDOT: PSS was improved by using biosynthesized gold-silver nanoparticles. The nanoparticles used were synthesized from red onion bulb extract. The optical absorption of the polymer was enhanced due to the scattering properties of the nanoparticles. The nanoparticles and PSS interactions reduced the electrostatic attraction between conductive PEDOT and insulating PSS, resulting in a quinoid PEDOT structural formation with enhanced electrical conductivity. The change in PEDOT conformations in the presence of nanoparticles was studied by Raman spectroscopy. The surface morphologies of the prepared thin films after incorporating nanoparticles in PEDOT: PSS were investigated using SEM. The conductivity was enhanced from 18.17 Scm-1 for reference PEDOT: PSS to 20.54, 31.72, and 60.84 Scm-1 for 30, 60, and 90 ?L NPs concentrations, respectively.