ZnFe2O4 thin films from a single source precursor by aerosol assisted chemical vapour deposition

A single source heterobimetallic complex [Fe-2(acac)(4)(dmaeH)(2)][ZnCl4] (1) (acac = 2,4-pentanedionate, dmaeH = N,N-dimethylaminoethanol), was synthesized in high yield. The complex was analyzed by melting point, Fourier transfer infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA). The structure of the cation was established by single crystal X-ray analysis on a derivative, [Fe-2(acac)(4)(dmaeH)(2)][ZnCl3(THF)](2)center dot THF (1a) (THF = tetrahydrofuran). TGA analysis showed that complex (1) undergoes facile thermal decomposition at 450 degrees C to give ZnFe2O4 residue. In-house designed aerosol assisted chemical vapour deposition equipment was used to deposit thin films of ZnFe2O4 on fluorine doped SnO2 coated conducting glass substrate at 450 degrees C. X-ray diffraction analysis proved the formation of crystalline ZnFe2O4 phase and scanning electron microscopy revealed the film morphology with well defined crystalline particles evenly distributed in the range 150-200 nm. The indirect and direct bandgap energies of the thin films were estimated to be 1.76 and 2.10 eV, respectively. (C) 2009 Elsevier B.V. All rights reserved.