Preparation and tribological properties of WS2 and WS2/TiO2 nanoparticles

A method was developed to prepare WS 2 and WS 2 /TiO 2 nanoparticles . A blue tungsten oxide precursor was synthesized from Na 2 WO 4 , CH 3 CSNH 2 , and HCl. WS 2 nanoplatelets was produced after sulfurizing the precursor at 300 °C. Nano-TiO 2 could be activated by HCl and provide active sites for the deposition of the precursor to produce WS 2 /TiO 2 nanoparticles after sulfurization. The as-prepared two nano-additives slightly affected the friction reduction of diisooctyl sebacate (DOS), but they, especially WS 2 /TiO 2 , remarkably improved the wear resistance of DOS. Compared with the pure DOS, the 0.75% WS 2 /TiO 2 -containing DOS decreased the wear volume by ∼81%. The anti-wear performance of WS 2 /TiO 2 is ascribed to the formation of a lubricating film and the synergistic lubrication effect of WS 2 and TiO 2 .