Optical properties and FT-IR spectra of PANI/f-MWCNT thin films

Abstract

Polyaniline (PANI) and PANI/f-MWCNT thin films have been synthesized by the in-situ chemical polymerization method. Ammonium persulfate (NH4)2S2O8 and hydrochloric acid (HCL) were used as an oxidizing agent and protonic acid dopant, respectively.  The f-MWCNT was added to PANI matrix to enhance and modify its optical properties. The films were deposited on glass substrates by dip coating method and its characterizations were done by UV-Vis (Ultra-Violet Visible Spectrophotometer) and FTIR (Fourier transform Spectroscopy) in the region of (650–2500) cm−1. The optical energy gap and optical constants such as the reflective index, the extinction coefficient and others were carried out from the optical measurements in the wavelength range (300-900) nm. The optical results indicate that the prepared films have allowed direct transition and the optical energy gap depends on the different weight percentages of f-MWCNT which was used as a dopant. FTIR spectrum shows several absorption peaks centered at around 1556, 692, 1235, 830, 1450 and 1280 cm−1 which consider the characteristic band peaks of polyaniline.