Seeded preparation of ultrathin FeS2 nanosheets from Fe3O4 nanoparticles

Abstract

FeS₂ nanomaterials with two-dimensional features hold great promise for electrochemical and photovoltaic applications. However, the preparation of ultrathin FeS₂ nanosheets is still challenging because of the lack of a tailor-made approach. In this work, FeS₂ nanosheets with a thickness of 2.1 nm are prepared through a Fe₃O₄-seeded approach. Uniform Fe₃O₄ nanoparticles are foremost synthesized via the standard method in organic media. The injection of a S solution leads to the replacement of O in Fe₃O₄ through anion-exchange, which generates (110) facet-enriched FeS₂ nuclei. The subsequent (110) facet-mediated oriented attachment and fusion of FeS₂ nuclei produce ultrathin FeS₂ nanosheets. As catalysts in the hydrogen evolution reaction, FeS₂ nanosheets exhibit good electrochemical activity.