Tris(dithiocarbamato)iron(III) complexes as precursors for iron sulfide nanocrystals and iron sulfide-hydroxyethyl cellulose composites

Abstract

ABSTRACTIron(III) complexes of dimethyldithiocarbamate and imidazolyl dithiocarbamate were synthesized and characterized by elemental analyses, FTIR, UV–VIS and the ligands by NMR spectroscopy. The complexes were thermolysed as single molecule precursors at 180°C to prepare octadecylamine (ODA) capped iron sulfide nanocrystals and iron sulfide-hydroxyethyl cellulose (HEC) composites. UV–VIS, PL, FTIR, P-XRD, HRTEM, FESEM and EDS were used to characterize the iron sulfide nanocrystals and corresponding HEC nanocomposites. XRD confirmed iron sulfide nanocrystal (NP1) from dimethyldithiocarbamate to be hexagonal pyrrhotite-5H, Fe9S10 crystalline phase while iron sulfide nanocrystals (NP2) from imidazolyl dithiocarbamate is in pyrrhotite, Fe11S12 crystalline phase. TEM images show that the iron sulfide nanocrystals have particle sizes in the range 24–32 nm for NP1 and 18–25 nm for NP2 iron sulfide nanocrystals. The optical band gaps of the iron sulfide nanocrystals obtained from Tauc plots are 3.83 and 4.16 eV for NP1 and NP2, respectively. IR spectra, FESEM surface morphology and EDS spectra of iron sulfide/HEC composites confirmed dispersion of the iron sulfide nanocrystals within the hydroxyethyl cellulose (HEC) matrix.