Polypyrrole-NiO hybrid nanocomposite: Structural,morphological, optical and electrical transport studies

Polypyrrole (PPy)-nickel oxide (NiO) hybrid nanocomposite thin films have been prepared by spin coating method. The PPy–NiO hybrid nanocomposites were characterized for structural, morphological, optical and electrical analysis, and the results were compared with the pure PPy films. The structural and optoelectronic properties of PPy–NiO hybrid nanocomposites are quite different from those of pure PPy and NiO nanoparticles, which were attributed to the strong interaction between the PPy and NiO nanoparticles. The XRD pattern shows that broad peak of PPy becoming weaker on increasing the content of NiO nanoparticles in the PPy–NiO hybrid nanocomposites. Also the diffraction peaks of NiO nanoparticles in PPy–NiO (10–50 wt%) nanocomposites were found to shift to lower 2θ values. The morphological studies revealed that the transformation of granular morphology of PPy to the nanospheres and clusters in the PPy–NiO hybrid nanocomposites. FTIR spectra of PPy–NiO hybrid nanocomposites, revealed that the main absorption at 1204 cm⁻¹ and 1559 cm⁻¹ are affected by the presence of NiO nanoparticle in pure PPy and get shifted to 1216 cm⁻¹ and 1570 cm⁻¹ respectively indicates, insertion of NiO nanoparticles in the PPy–NiO hybrid nanocomposite. UV–vis absorption spectrum of PPy corresponding to λ_max = 442 nm is blue shifted to λ_max = 375 nm in the PPy–NiO hybrid nanocomposites, reveals strong interaction between PPy and NiO nanoparticles. The room temperature dc electrical conductivity is increased from 8.66 × 10⁻⁹ to 4.08 × 10⁻⁷ (Ω/cm)⁻¹ as the content of NiO nanoparticles increased from 10 to 50 in wt% in the PPy–NiO hybrid nanocomposites.