Effect of Ag₂ S nanoparticles on optical, photophysical, and electrical properties of P3HT thin films

In the present work, optical, electrical, and photophysical properties of poly(3-hexylthiophen)/silver sulphide (P3HT/Ag₂ S) nanocomposites thin films were investigated. New amorphous dispersion formula was used to fit the experimental ellipsometer data and it was observed that the both refractive index (n) and absorption index (k) increased for hybrid films compared with pure P3HT film. The photophysical properties of fabricated films were examined by recording the photoluminescence (PL) and time resolved fluorescence spectra. The PL quenching in hybrid films signalled the formation of a charge transfer complex between host (P3HT) and guest (Ag₂ S). The fluorescence average life time was noted to drop to 94 ps for hybrid P3HT:Ag₂ S 1:2 film compared with 126 ps for pristine P3HT. Finally, the electrical properties of fabricated films were measured using the Hall effect systems. The surface resistivity (ρ) of pure P3HT thin films was found to be 9.70 × 10⁴ Ω.cm, which decreased slightly for Ag₂ S/P3HT hybrid films.