An investigation of structural, optical, and electrical properties of poly(3-hexylthiophene)/reduced graphene oxide nanocomposites for electronic and optoelectronic applications

Poly(3-hexylthiophene)/reduced graphene oxide nanocomposites (P3HT/rGO) were successfully prepared starting with 3-hexylthiophene (3HT) monomer. H-1 NMR was utilized to determine the regioregularity of the polymer and the degree of polymerization. The interaction of rGO was identified by employing Fourier transform infrared spectroscopy and X-ray diffraction (XRD). Besides, the XRD results revealed the crystallinity was enhanced with the increment of rGO. Upon filling with rGO, High-resolution transmission electron high-resolution transmission electron microscopy images manifested a fluffy morphology, while field emission scanning electron microscope demonstrated a high level of compactness and uniformity. Optical spectrophotometry (UV-Vis-NIR) was implied to determine the impact of rGO on the optical properties. It was found that the bandgap was reduced upon the addition of rGO. The temperature and frequency-dependent electrical properties including complex permittivity, tangent loss, complex electrical modulus, impedance, and conductivity for revealing both the dipolar relaxation and charge transportation were investigated. It is revealed that P3HT/rGO has significantly higher conductivity values compared to P3HT. Further, the temperature dependence of the Dc-conductivity for pure P3HT was governed by the Vogel-Fulcher-Tamman (VFT) approach, whereas it was altered to Arrhenius upon the inclusion of rGO. The fact that the P3HT/rGO nanocomposite has a higher epsilon' value, lower tangent loss, and higher conductivity than the pristine P3HT, suggested these nanocomposites are more favorable than pure P3HT in optoelectronic and thermoelectric applications.