Synthesis and characterization of thin film of polyaniline carboxymethyl cellulose (PANI CMC) for optoelectronic device application

Abstract

In this work we report the investigation of the optical and structural properties of polyaniline carboxymethyl cellulose thin film. By using in situ polymerization technique, thin films of PANI CMC were synthesized at various deposition time of 40 seconds, 80 seconds and 120 seconds from an ink solution. The thin films were characterized by UV-VIS spectroscopy and scanning electron microscopy. The optical properties revealed that PANI CMC has absorption peaks at 340 nm and 800 nm. The absorption peak exhibited by the films around 340 nm can be attributed to the electron transition from the highest occupied molecular orbital (HOMO) to the lowest unoccupied molecular orbital (LUMO) corresponding to the π → π* electronic transition while The peak at about 800 nm (polaron π*) corresponds to molecular excitation transition and the conducting phase of the polyaniline. The band gad energy at 2.7 eV corresponds to the emission of polymer in the solid state and demonstrating the optical properties of the polymer. SEM analysis indicates the films are porous to an extent with the formation of some particles on its surface *Correspondence to: Anene Chinelo Rita, Department of Physics and Industrial Physics, Nnamdi Azikiwe University, Awka, Nigeria, E-mail: rc.anene@unizik. edu.ng and A. O.C. Nwokoye@unizik.edu.ng