Synthesis and characterization of conjugated PVA/PANi blend doped with functionalized Graphene for Thermoelectric Applications

Abstract

Flexible nanocomposite thick films consisting of PVA0.7PANi0.3 polymer blend doped with different concentrations of functionalized Graphene (FGNPx) (where x = 0, 5, 10, 15, 20, and 25 wt.%) were synthesized using the solution cast technique. Scanning Electron Microscopy (SEM), X-ray diffractometer (XRD), Energy Dispersive Spectroscopy Analysis (EDX), and Fourier- Transform Infrared Spectra (FT-IR) were used to study the structure of the samples. The results showed that the ordered structure, its orientation, the PANIs' well dispersion, the 𝜋 − 𝜋 stacking, and the electrostatic forces play a significant role in enhancing the interfaces between the polymer blend and the FGNP. Thermogravimetric Analyses (TGA) and Thermoelectrical analyses (TE) showed that the PVA-PANI conducts a promised conjugated blend for thermoelectric applications. The introduction of the FGNP contents into the blend increased the TE measurements as the DC electrical conductivity ≈ 0.0114 (S.cm−1), power factor ≈ 3.93x10− 3 (W.m−1 .K−2 ), and Z.T. ≈ 8.4x10− 7, for the 25 wt. % FGNP nanocomposite film. The effect of the polymers’ phonon contribution in the thermal conductivity controlling and enhancing the thermal stability of the prepared nanocomposite films.