Green-synthesized Ag2O- Doped Polyaniline Nanocomposites: Structural, Optical, and Electrical Properties

Abstract

Polyaniline (PANI) nanocomposites doped with silver oxide (Ag₂O) nanoparticles were successfully synthesized using an ultrasonic-assisted oxidative polymerization technique. Ag₂O nanoparticles were prepared via a green chemistry approach using tea leaf extract as a reducing and stabilizing agent. The prepared nanoparticles were thermally treated under a nitrogen atmosphere before incorporation into the polymer matrix. Nanocomposite samples containing different Ag₂O concentrations (5, 7, and 10wt.%) were fabricated and labeled S1-S3. Characterization of the synthesized polyaniline (S1-S3) was carried out by FT-IR, UV-visible spectroscopy, X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), and energy-dispersive X-ray spectroscopy (EDX). XRD results confirmed the semi-crystalline structure of PANI and revealed that crystallite size ranged from 4 to 13 nm depending on Ag₂ONPs loading. Optical studies showed that the energy band gap (Eg) decreased from 3.2 eV for pure PANI to 2.25eV for the 10 wt.% nanocomposite(S3). Electrical conductivity (σdc) measurements performed over the temperature range of 20-170°C(293-443K) show a significant increase in conductivity with increasing Ag₂O content, with the highest conductivity observed for the S3 sample at 90°C. The results show that the fusion of Ag₂ONPs effectively perfects the structural ordering and charge transport properties of polyaniline. These perfections indicate the possibility of applications in electronics and sensors.