Synthesis of new cobalt(III) Schiff base complex: A new precursor for preparation Co3O4 nanoparticles via solid-state thermal decomposition

• In this study, NiO nanoparticles were successfully prepared via solid-state thermal decomposition route.
• Solid-state thermal decomposition method is a good candidate for synthesized nanosize of manganase oxide.
• The particle size and morphology of NiO nanoparticles may be controlled by using various methods.

A new mononuclear octahedral cobalt(III) Schiff base complex [CoL3] (L = N-salicylidin-2-chloroethylimine) has been synthesized and characterized by elemental analyses (CHN) and FT-IR spectroscopy and used as precursor for preparation of Co3O4 nanoparticles. The crystal structure of this compound has been determined by single-crystal X-ray diffraction. The coordination sphere about cobalt(III) ion consists of three phenolato oxygens and three imino nitrogen atoms from three Schiff base ligands, thus forming a distorted octahedral geometry. Each Schiff base ligand acts as a chelate using phenolato oxygen and imino nitrogen. Subsequently, pure phase Co3O4 nanoparticles, with an average size in the range 10–20 nm, were obtained by solid-state thermal decomposition of the synthesized complex at 450 °C under air atmosphere for 3 h. The Co3O4 nanoparticles were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM).