One pot synthesizing of cobalt (III) and (IV) oxides/polypyrrole nanocomposite for light sensing in wide optical range

Abstract

A highly porous potato-shaped nanocomposite, Co(111) and Co(IV) oxide/polypyrrole (Co2O3-Co3O4/Ppy), is synthesized employing a one-pot procedure involving the slow oxidation of pyrrole using Co(NO3)2. The exceptional physical characteristics of this nanocomposite are accompanied by impressive optical properties, marked by a bandgap of 1.72 eV. Its absorbance spans across the UV, visible (Vis), and infrared (IR) regions, making it a promising candidate for optoelectronic applications such as photodetectors designed for light sensing within this extensive optical range that encompasses a substantial portion of the electromagnetic spectrum.
This Co2O3-Co3O4/Ppy thin film photodetector is subjected to electrical testing under varying light conditions, leading to the determination of the photocurrent density (Jph) value of 0.26 mA.cm-2. When evaluated under different monochromatic light sources ranging from 340 to 730 nm, distinct Jph values are observed for each wavelength, reflecting the nanocomposite's ability to effectively interact with photons across this spectrum. The measured responsivity (R) and detectivity (D) values further underscore the photodetector's efficiency. At 340 nm, the R and D values stand at 1.22 mA.W-1 and 0.275x109 Jones, respectively. Similarly, at 730 nm, these values are 1.21 mA.W-1 and 0.270x109 Jones. The combination of these favorable findings, including cost-effectiveness and high stability, position the Co2O3-Co3O4/Ppy nanocomposite as an optimal choice for a wide range of industrial applications, attesting to its potential impact in the field.