Correlation among local structure, magnetic, structural and electronic properties in polyol synthesized iron sulfide (FeS2) nanoparticles

A comparatively new and important cost and time effective Polyol method has been utilized for the preparation of FeS(2)nanoparticles (NPs), while their crystallite size, bonding as well as nearest neighbor atomic information was obtained from XRD, FTIR, Mossbauer, FE-SEM, EDX spectroscopy techniques. The average crystallite size was found to be similar to 28 nm and a very small tangential strain due to the spherical shape of the particle was seen in the prepared sample. The bond length of Fe-S bond was estimated to be similar to 0.29 nm and that of S-S bond was similar to 0.22 nm using VESTA software confirming the Pyrite FeS2 structure in agreement with the XRD of these NPs. Also, the sample shows an octahedral geometry. Both XRD and Mossbauer spectra indicate that no impurity phase is present in these Pyrite NPs. Using Mossbauer, the average electric Quadrupole splitting (Delta E-Q) and average isomer shift (delta), for Pyrite FeS2 at 300 K are found to be 0.596 +/- 0.0039 mm/s and 0.311 +/- 0.0023 mm/s respectively. From the Isomer shift, +2 oxidation state is confirmed. The FTIR revealed various vibrations modes of FeS2 nanoparticles (Fe=S, S-S and Fe-S bonds at their respective positions). Corresponding FE-SEM and EDX measurements revealed the formation of agglomerated spherical particles with the Fe:S ratio of -1:1.46 confirming the pyrite structure. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

A Polyol method was used for the preparation of FeS2 nanoparticles, with an average crystallite size of around 28 nm and a Pyrite FeS2 structure confirmed. XRD and Mossbauer spectra indicated no impurity phase present.