Synthesis and characterization of iron tin oxide thin films from single source bimetallic precursors

Abstract

Two new bimetallic precursors, [(C5H5)Fe(C 5H4)COOSn(C4H9)3] (A 1) and [(C5H5)Fe(C5H 4)COOSn(C6H5)3] (A2), were synthesized by reacting 4-ferrocenylbenzoic acid with tributyltin chloride and triphenyltin chloride in refluxing toluene. Single crystal analysis showed the molecules to adopt the usual trigonal bipyramidal geometry, the ferrocene ligand being perpendicular to the phenyl ring and tin carboxylate cycle. Thermogravimetric studies revealed the decomposition of both synthesized compounds in the range 450-500°C, leaving a residue corresponding to the mass of SnO2·1/2Fe2O3 for A1 and SnO2·Fe2O3 for A2. The synthesized compounds were used as precursors for depositing FeSnOx thin films by aerosol assisted chemical vapor deposition (AACVD) on a glass substrate (at 400 and 450°C). Scanning electron microscopy (SEM) of the thin films showed the formation of spherical globules at 450°C for both precursors, with the average roughness of the thin films being 2.48 and 3.41 nm for A1 and A2, respectively. The XRD pattern for A 1 at 450°C shows the incorporation of the iron in a substitutional position in the tin oxide lattice due to the small difference in their atomic radii. In the case of A2, only spinel iron oxide (magnetite and maghemite) with the dominance of maghemite is found. © 2013 Elsevier Ltd. All rights reserved.