Optical dispersion parameters and stability of poly (9, 9′-di-n-octylfluorenyl-2.7-diyl)/ZnO nanohybrid films: towards organic photovoltaic applications

Conjugated polymer nanohybrid films were prepared from poly (9,9′-di-n-octylfluorenyl-2.7-diyl) (PFO) and zinc oxide (ZnO) nanoparticles. ZnO nanopowder was prepared by the solgel method, different ratios of PFO/ZnO nanohybrids have been prepared using solution blending method. Then, the blends were spin-coated onto glass substrates at 2000 rpm for 1 min. and subsequently dried at room temperature. XRD and TEM were used to determine the structural properties, while UV–Vis and photoluminescence spectrophotometers were employed to investigate the optical properties of the films. The spectral distribution of specular reflectance were used to calculate the refractive index n ( λ ) and the optical dispersion parameters were determined according to Wemple and Didomenico (WD) model. The effect of ZnO NPs on the direct and indirect band gap energies, photo- and thermal stability was also discussed. A significant enhancement in the light emitting properties has been observed by increasing the concentration of ZnO NPs. (paper)