Preferentially grown nanostructured iron disulfide (FeS2) for removal of industrial pollutants

Abstract

Preferentially grown nanostructured materials show extraordinary properties even compared with their nanostructured counterparts. The present study deals with a preferentially grown iron disulfide (FeS₂) pyrite phase. Pyrite (111) shows high catalytic activity towards methylene blue (MB) and a textile dye (Synazol Yellow K-HL). In the present study, pyrite (111) was successfully synthesized using a low cost effective hydrothermal method and then employed as a photocatalyst for degradation of methylene blue as well as the textile dye Synazol Yellow K-HL. The structural, morphological and optical features of the synthesized FeS₂ material were confirmed by X-ray diffraction and UV-visible spectrophotometry. The as synthesized powder was also characterized by Raman spectroscopy to confirm the pyrite phase formation. The dye degradation is based on a mechanism involving reactive oxygen species produced from a photo Fenton like process. The maximum degradation efficiency of a methylene blue dye solution and the textile dye Synazol Yellow K-HL was 95.90% and 99.29%, respectively, after 120 minutes with a 1 g L⁻¹ FeS₂ catalyst dose. This work proposes a vision to develop transition metal based photocatalysts for degradation of harmful organic contaminants present in waste water and for many other environment friendly applications.