Synthesis and optical characterization of polyaniline /iron oxide nanocomposite

Polyaniline-iron oxide nanocomposites were successfully synthesized by in-situ polymerization method. The polyaniline metal oxide nanocomposites formed were characterized using Stellar Net UV - VIS - NIR spectrometer (Blue - Wave Miniature; Model: UVNb). The optical properties investigated include; absorbance, transmittance, reflectance, refractive index, extinction coefficient and energy band gap. Our results show that the absorbance of polyaniline - iron oxide nanocomposites decreases as amount of iron oxide nanoparticles increased with a peak value of approximately 1.00. Transmittance of polyaniline- iron oxide (PANI/Fe₂O₃) nanocomposites decreases as amount of iron oxide nanoparticles increased with a peak value of 58% at 800nm. Reflectance within the regions of the electromagnetic spectrum considered was found to be very low. A peak refractive index value of 2.64 was obtained at 700nm for the synthesized iron oxide nanoparticles. The extinction coefficient of our synthesized nanocomposites decreased with increase in the concentration of iron oxide nanoparticles. Optical band gap of polyaniline iron oxide nanocomposites ranged from 2.50 eV to 2.20 eV.Our x - ray diffraction result show that the PANI/Fe₂O₃ nanocomposites formed have Orthorhombic crystal structure with preferred orientation in the (111) plane.