Synthesis and tribological properties of WS2 nanoparticles

The WS2 nanoparticles were synthesized by a reaction of the precursor of tungsten-oxide nanoparticles with sulfur powder under hydrogen atmosphere. The reaction was accomplished in a home-made reactor and hydrogen was used as reducing gas instead of H2S to minimize the pollution caused by using H2S. The synthesis route was simple and high-purity products could thus be obtained. The structure and morphology of the products were characterized by XRD, SEM, TEM and high resolution transmission electronic microscope (HRTEM). As an additive for base oil, the tribological properties of WS2 nanoparticles were measured by MS-T3000-instrument. The results show that the nanoparticles thus prepared are in spherical-like shape with an average size of less than 50 nm. It is revealed that the WS2 nanoparticles have excellent tribological performance as an additive to base oil.