Synthesis and Properties of Semiconducting Iron Pyrite (FeS2) Nanowires

We report the growth and structural, electrical, and optical characterization of vertically oriented single-crystalline iron pyrite (FeS2) nanowires synthesized via thermal sulfidation of steel foil for the first time. The pyrite nanowires have diameters of 4-10 nm and lengths greater than 2 mu m. Their crystal phase was identified as cubic iron pyrite using high-resolution transmission electron microscopy, Raman spectroscopy, and powder X-ray diffraction. Electrical transport measurements showed the pyrite nanowires to be highly p-doped, with an average resistivity of 0.18 +/- 0.09 Omega cm and carrier concentrations on the order of 10(21) cm(-3). These pyrite nanowires could provide a platform to further study and improve the physical properties of pyrite nanostructures toward solar energy conversion.