Synthesis, Characterization and Magnetic Properties of Bi-metallic Copper Complex, as a Precursor for the Preparation of CuO Nanoparticles and Its Application for Removal of Arsenic from Water

Abstract

This work involved the synthesis of bimetallic complex of [Cu(bpy)3][Cu(dipic)2]·2H2O (1) where dipic is pyridine-2,6-dicarboxylic acid and bpy is 2,2′-bipyridine, through the reaction of [Cu(bpy)5]2+ with [Cu(dipic)2]2−. The structure of complex (1) was characterized by, Fourier transform infrared spectroscopy (FT-IR), UV–Vis spectroscopy, atomic absorption spectroscopy (AAS), elemental analysis and conductivity measurement. Also, thermal behavior of the complex was studied by thermo-gravimetric analysis (TGA and DTA) and the morphology of the complex was studied by scanning electron microscopy technique (SEM). The complex (1) was used as a precursor for the preparation of ferromagnetic nanoparticles of CuO by thermal decomposition at 600 °C. CuO nanoparticles were characterized by FT-IR spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Magnetic properties of complex (1) and CuO nanoparticles were studied at room temperature by vibrating sample magnetometer (VSM). The results of VSM indicate paramagnetic and ferromagnetic feature of and CuO nanoparticles, respectively. CuO nanoparticles with specific surface area of 69 m2/g and particle size of 20 nm were used as adsorbents to remove arsenic from contaminated water. The highest amount of arsenic adsorption on the surface of CuO nanoparticles occurs at pH 8 to 9 and contact time of 40 min. Based on this study, copper oxide nanoparticles can be effectively used to remove arsenic from water. Magnetization curves at 298 K (a) complex of [Cu(bpy)3][Cu(dipic)2]·2H2O: (b) nanoparticles of CuO