Synthesis and crystal structure of cobalt(II) Schiff base precursor for cobalt oxide thin film by thermal chemical vapor deposition

The tetrahedral Schiff base complex bis(N-isopropylsalicylaldimine)cobalt(II) [Co(saliprn)2] (CSI) was prepared by template method. The complex was characterized by FT-IR, mass spectroscopy, TG/DTA and single crystal X-ray structure determination analysis. The dynamic TG analysis showed that the complex is completely volatile. The equilibrium vapor pressure of the complex was studied by non-isothermal and isothermal thermogravimetric transpiration techniques over the temperature range of 474–514 K. The Ea (48.4 kJ mol−1) and ΔHsub (111.54 kJ mol−1) for the complex and expression for temperature dependence of vapor pressure (Pe) were obtained. The thermal behavior of the cobalt(II) complex was studied by thermogravimetry techniques using different non-isothermal heating rates under nitrogen atmosphere. The complex was found to be volatile and used in thermal chemical vapor deposition for the development of nanocrystalline cobalt oxide thin films over silica substrates. These nanocrystalline thin films were analyzed by XRD and SEM confirmed the presence of Co3O4 phase with almost nil carbon.

Graphical abstractA metallo-organic CVD precursor bis(N-isopropylsalicylaldimine)cobalt(II) was synthesized by template method showing orthorhombic space group Pbac. In the crystal structure cobalt(II) is surrounded by two Schiff base ligands forming a distorted tetrahedron. The complex was found to be volatile and used in thermal chemical vapor deposition (TCVD) for the development of nanocrystalline cobalt oxide thin films.Figure optionsDownload full-size imageDownload as PowerPoint slide