Study of nanostructured metal sulfides produced by self-propagating high-temperature synthesis

In this work results of a study of nanostructured metal sulfides obtained by self-propagating high-temperature synthesis from metal nanopowder and elementary sulphur are presented. The initial iron, copper, tungsten and molybdenum nanopowders were produced by electrical explosion of wires in argon at operating voltage 24-29 kV. Stoichiometric mixtures of metal nanopowders and sulphur were pressed into cylindrical samples which were then placed into the reactor - a constant pressure chamber. Synthesis was carried out in argon at 30 atm. The initial metal nanopowders and synthesized metal sulfides were characterized by XRD, SEM, DTA-TGA methods. According to the XRD analysis the main phases in the obtained powders were FeS, CuS, WS₂ and MoS₂. The mean size of coherent scattering regions was 35 nm for FeS, 49 nm for CuS, 58 nm for WS₂ and 78 nm for MoS₂. According to the SEM results particles of tungsten and molybdenum disulfides were agglomerated and had a nanolamellar structure. As DTA-TGA shows synthesized nanolamellar WS₂ and MoS₂ are thermostable up to 400°C.