Catalytic Impact of Nano-Supramolecular Complex Based on Lead and Quinoline-2-Carbxylic Acid Ligand as Efficient Catalyst for Removal of Hazardous Materials From Wastewater

Abstract

Under ultrasonication, the nanoscale supramolecular complex [Pb (QCA)₂]_n (NSC1) was formed by the self-assembly of lead nitrate and quinoline-2-carboxylic acid (QCA) as linking ligand. Pb^II exhibits a (O₂N₂) distorted square planner geometry, where the Pb^II atom coordinates to two QCA ligands, according to single crystal X-ray diffraction of 1. With a packing structure of 1, facing molecules are arranged in parallel planes and joined by multiple H-bonds and π-π stacking to form a three-dimensional network. NSC1 was examined using a variety of structural characterization techniques as well as spectrum studies. Despite the well-documented toxicity of lead, which is utilized in various products, the nanoscale supramolecular complex [Pb (QCA)2]n (NSC1) demonstrates considerable safety owing to its stability, remaining unaffected by degradation mediums, as corroborated by different techniques. So, under UV or ultrasonic wave conditions, it has been demonstrated that the heterogeneous catalyst NSC1 exhibits significant catalytic activity in presence of H₂O₂ against the breakdown of the indicated pollutants, indigo carmine (IC) and phenol (Ph), in very short times. Using the disodium salt of terephthalic acid, the photoluminescence probing method was applied to ascertain the reactive oxygen species and the reaction process mechanism.