Nanostructured Polypyrrole Powder: A Structural and Morphological Characterization

Polypyrrole (PPY) powder was chemically synthesized using ferric chloride (FeCl3) and characterized by X-ray diffraction (XRD), Le Bail Method, Fourier Transform Infrared Spectrometry (FTIR), and Scanning Electron Microscopy (SEM). XRD pattern showed a broad scattering of a semicrystalline structure composed of main broad peaks centered at 2 theta = 11.4 degrees, 22.1 degrees, and 43.3 degrees. Crystallinity percentage was estimated by the ratio between the sums of the peak areas to the area of amorphous broad halo due to the amorphous phase and showed that PPY has around 20 (1)%. FTIR analysis allowed assigning characteristic absorption bands in the structure of PPY. SEM showed micrometric particles of varying sizes with morphologies similar to cauliflower. Crystal data (monoclinic, space group P 21/ c, a = 7.1499 (2) angstrom, b = 13.9470 (2) angstrom, c = 17.3316 (2) angstrom, alpha = 90 angstrom, beta = 61.5640 (2) angstrom and gamma = 90 angstrom) were obtained using the FullProf package program under the conditions of the method proposed by Le Bail. Molecular relaxation was performed using the density functional theory (DFT) and suggests that tetramer polymer chains are arranged along the "c" direction. Average crystallite size was found in the range of 20 (1) angstrom. A value of 9.33 x 10(-9) S/cm was found for PPY conductivity.