Synthesis and optoelectronic properties of conductive nanostructured poly(aniline-co-o-aminophenol) thin film

Poly(aniline-co-o-aminophenol) copolymer (PANoAP) is synthesized based on modified chemical route in highly acidic medium by using ferric chloride as an oxidizing agent in the presence of polyethylene glycol with molecular weight 200 as a surfactant. The chemical structure of resulting PANoAP is characterized by Fourier transform infrared FT-IR and (HNMR)-H-1 spectroscopy. The morphological analysis was carried out by scanning electron microscope. The resulting copolymer exhibits nanostructured polydispersity. The electrochemical behavior of the copolymer is studied by cyclic voltammetry in 0.2 M H2SO4 solution, at a scan rate of 50 mV s(-1). The potentials of oxidative signals of the PANoAP are found to be 0.141, 0.086, - 0.0083 and - 0.176 eV respectively. The reduction of quinoid structure in the copolymer backbone is detected by a broadly cathodic peak at 0.144 V and anodic signal at 0.141 V. Thin film of PANoAP is fabricated by spin coating with a thickness of 70 +/- 3 nm. Based on the X-ray diffraction analysis, the PANoAP has crystalline nature depending on the strong interchain hydrogen bonding, and the electrostatic (dipole-dipole) interactions between the copolymer chains. The onset energy band value of the PANoAP thin film is found to be 2.19 eV. In addition, the electrical conductivity of the PANoAP thin film was found to be 6 x 10(-2) S cm(-1) at room temperature.