Perchlorate supported Cu(II) based 1D polymeric chain containing 1,10-phenanthroline: Synthesis, characterization and adsorption of organic dyes and heavy metal ions

A one-dimensional (1D) copper(II) polymeric chain, [Cu(1,10-phen)(ClO4)(H2O)2]n (1), was synthesized by reacting Cu(ClO4)2·6H2O with 1,10-phenanthroline in the presence of triethylamine in methanol. X-ray crystallography revealed that 1,10-phenanthroline functions as a bidentate ligand, while ClO4- serves as perchlorate bridged linkers generated a 1D-polymeric chain. Adsorption studies were conducted for1 against methylene blue (MO), methyl orange (MO) and heavy metal ions such as copper (Cu2+) and cadmium (Cd2+) respectively. In the context of MB maximum adsorption efficiency by adsorbent 1 was interpreted to be the highest (85.13%) at pH 3; however, for MO, it was 68.10% whereas, in case of heavy metals, maximum adsorption capacity was recorded for Cd (52.20%), in contrast to Cu (34.87%). The adsorption mechanism was rationalized by the fact that the dye molecules equipped with aromatic moieties interacted with 1 through electrostatic interaction, π…π interaction and OH...π interaction. However, with reference to heavy metals, 1 primarily elucidates electrostatic interactions with the metal ions (Cd+2, Cu+2). The adsorption behavior of MB and MO significantly corroborated a strong agreement with the pseudo-second-order pattern, which suggests chemisorption, as the main mechanism.