Synthesis of Iron Sulfide Thin Films and Powders from New Xanthate Precursors

A series of novel alkylxanthato iron(III) precursors [Fe(S2COR)3] (R = n-butyl, (1); 2-butyl, (2); 2-methoxyethyl, (3); and 2-ethoxyethyl (4)) have been synthesised and their single crystal X-ray structures have been studied. All as-synthesised complexes were used as single-source precursors for the deposition of iron sulfide thin films as well as nanostructures using spin coating technique and solventless thermolysis respectively. Cubic pyrite was obtained using n-butyl xanthato iron(III) and 2-butyl xanthato iron(III) complexes in the temperature range of 200 to 300°C. Structural and morphological investigations using XRD and SEM have been performed to ascertain the crystallinity and morphology of as-prepared thin films and nanostructures. The elemental composition was determined using energy dispersive X-ray (EDX) spectroscopy. The optical band gaps of pyrite thin films produced by these methods were direct with estimated values in the range 1.6 to 2.3 eV.