Structural, electrical, and optical characteristics of polypyrrole-doped DBSA/ZrO₂ nanocomposites

Polypyrrole (PPy) nanocomposites doped with dodecylbenzene sulfonic acid (DBSA) and integrated with zirconium dioxide (ZrO₂) nanoparticles were successfully synthesized through an in-situ polymerization technique. Comprehensive structural and morphological characterizations were carried out using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM–EDX). The results confirmed the formation of well-defined nanocomposites, with strong interactions between PPy-DBSA and ZrO₂ nanoparticles. SEM analysis revealed a dual-phase morphology characterized by platelet and flake-like structures with an increase in grain size of 195 nm, while EDX confirmed the distribution of zirconium within the PPy matrix. Current–voltage (I–V) characteristics confirm the ohmic behavior of all the nanocomposites. The electrical conductivity measure from I-V curves for PPy (2.18 × 10–4 S.cm−1), PPy-DBSA (2.46 × 10–3 S.cm−1), PPy-DBSA-2% ZrO2 (3.43 × 10–3 S.cm−1), and PPy-DBSA-8% ZrO2 (7.8 × 10–2 S.cm−1). Optical studies using Tauc’s plot method to calculate the optical band gap of 3.50 eV for PPy-DBSA-8% ZrO₂ nanocomposite, equated to pristine PPy. The decreased in optical band gap, along with enhanced AC conductivity, highlights the improved electronic properties of the nanocomposites. These findings suggest that PPy-DBSA-ZrO₂ nanocomposites, particularly those with 8% ZrO₂ loading, are promising candidates for applications in electronic devices and related fields.