Bird nest-like shape of polypyrrole-iodide/iodine complex nanocomposite with highly optical and morphological behavior for green hydrogen generation

Abstract

A novel bird nest-like structured complex nanocomposite, known as polypyrrole-iodide/iodine (Ppy-I/I₂), has been successfully synthesized using a one-pot oxidation reaction involving pyrrole and iodine materials. This complex nanocomposite exhibits highly promising characteristics both in terms of morphology and optics properties. The distinctive morphological features of the Ppy-I/I₂ complex nanocomposite are particularly noteworthy. Its bird nest-like structure consists of particles with well-defined cavities inside and small particles adorning the exterior surfaces. The distinctive morphology significantly improves the active sites and acts as an efficient photon trap, enhancing its exceptional optical properties. The bandgap of this composite measures 2.45 eV, which is a significant advantage for a polymer-based complex composite. This bandgap value makes it particularly applicable, especially in the realm of optoelectronics and photoelectrochemical processes. One of the standout applications for this complex nanocomposite is its use as a photocathode for the H₂ generation using the Red Sea water. Under various light conditions: white light and specific photon wavelengths, the photocathode demonstrates its efficiency. The current density (J_ph) values obtained are highly indicative of its performance, reaches − 0.8 mA cm⁻² under white light. Moreover, at temperatures 30–50 °C, the J_ph values show a notable improvement, rising from − 0.8 to − 0.89 mA cm⁻², which highlights the photocathode's versatility and potential for enhanced hydrogen generation.