Viable route for the synthesis of the anhydrous Co(hfac)2 adduct with monoglyme: a useful precursor for thin films of CoO

Abstract

The [Co(hfac)₂·CH₃OCH₂CH₂OCH₃] adduct was synthesised and investigated by X-ray crystal structure, mass spectra, TG-DTG thermal measurements and infrared transmittance spectroscopy. X-Ray single crystal data provide evidence of a slightly distorted octahedral cobalt cation, coordinated with four oxygen atoms of two hfac anions and two oxygens of the monoglyme molecule. Deposition experiments, in a low-pressure horizontal hot-wall reactor, on optically transparent SiO₂ substrates, using the title complex, resulted in CoO films. XRD measurements show that CoO consists of cubic, highly oriented, crystals. The surface atomic composition of the films was investigated by XPS. No fluorine contamination was detected.