Magnetically separable tris(N,N-difurfuryldithiocarbamato-S,S’)iron(III), micro and nano iron sulfide photocatalysts for the degradation of dyes

Abstract

Tris(N,N-difurfuryldithiocarbamato-S,S’)iron(III) (1) was prepared and its structure was verified utilizing experimental and computational analysis. Complex 1, comprises neutral and discrete molecule, in which the Fe(III) cation is coordinated by three N,N-difurfuryldithiocarbamate ligands within a slightly distorted S6 octahedral geometry. Density functional theory (DFT) calculations were conducted to study the reactivity and stability descriptors. Solvothermal decomposition of 1 in chloroform and diethylenetriamine yielded iron sulfide microparticles (FeS1). Heating 1 in diethylenetriamine to 60° for 45 min gave iron sulfide nanoparticles (FeS2). The micro and nanoparticles were characterized for their size, band gap energy, composition and structure by powder X-ray diffraction (PXRD), Field emission scanning electron microscopy (FESEM), Energy dispersive X-ray spectroscopy (EDS) and UV–Vis diffused reflectance spectroscopy. PXRD analysis reveals that iron sulfides, FeS1 and FeS2, are present as a hexagonal FeS phase. FESEM analysis show that the solvent chloroform affect the shape and size of iron sulfide nanoparticles. Methylene blue dye was used to examine the photocatalytic properties of complex 1 and iron sulfides (FeS1 and FeS2) under UV irradiation. The percentage degradation of dye in the presence of 1, FeS1 and FeS2 are 99%, 99% and 93%, respectively at 90 min of exposure time.