Thermal, optical and temperature-dependent electrical properties of poly(aniline-co-pyrrole)/copper alumina nanocomposites for optoelectronic devices

The article deals with the investigation of structural, thermal and temperature-dependent alternating current (AC) parameters of hetero-structures generated by the reinforcement of copper alumina (Cu-Al2O3) nanoparticles within the poly(aniline-co-pyrrole) (PANI-co-PPy). Further, the effect of reinforcement of Cu-Al2O3 on the direct current (DC) conductivity of the copolymer was equated with various theoretical models. Compared with the pristine copolymer, the ultraviolet-visible (UV-visible) spectrum of (PANI-co-PPy)/Cu-Al2O3 nanocomposites manifested a redshift in absorbance and the least optical bandgap energy was observed for 5 mass percentage (mass %) nanocomposite. Field emission scanning electron microscopy confirmed the effective reinforcement of Cu-Al2O3 nanoparticles within the PANI-co-PPy. The thermogravimetric analysis profile demonstrated a delayed thermal degradation for copolymer nanocomposites. The alternating current (AC) conductivity and dielectric properties were enhanced with a rise in temperature and content of nanofillers (up to 5 mass % loading). Further, the activation energy was found to be reduced with the temperature indicating the semiconductive behavior of synthesized nanocomposites. The Nyquist plot of copolymer nanocomposites showed two distinct areas, an incomplete semicircle and a rapid spike. The diameter of the semicircle was decreased with temperature. The DC conductivity of nanocomposites was enhanced with the reinforcement of Cu-Al2O3 nanofillers due to the enriched number of charge carriers accumulated within the nanocomposites. Finally, DC conductivity values were equated using Scarisbrick, Bueche and McCullough theoretical models. The McCullough model was in good agreement with measured DC conductivity as this model explains the dependence of DC conductivity with the quantity of filler and conductive pathway generated between the interfaces. Based on the results, these synthesized copolymer composites can be used in highly durable electronic devices such as supercapacitors, electrochemical sensors and optoelectronics.

Automated summary

This article investigates the effect of Cu-Al2O3 reinforcement on the structural, thermal, and temperature-dependent AC parameters of PANI-co-PPy composites. The study finds that the addition of Cu-Al2O3 enhances the conductivity and dielectric properties of the composites, making them suitable for durable electronic devices.