Effect of modification agent on the tribological properties of PbO nanoparticles

Dihexadecyldithiophosphorate (DDP) monolayer capped PbO nanoparticles and oleic acid (OA) monolayer capped PbO nanoparticles were synthesized using chemical method. Transmission electron microscope (TEM) and four-ball wear machine were used to evaluate the morphologies and tribological behaviour of the prepared nanoparticles, respectively. Results indicate that the prepared nanoparticles are both well-distributed with the average diameter of about 5 nm. Both DDP capped PbO nanoparticles and OA capped PbO nanoparticles can remarkably improve the antiwear ability of liquid paraffin as oil additives. However, OA capped PbO nanoparticles exhibit good friction-reducing performance, but DDP capped PbO nanoparticles can't reduce the friction coefficient as compared to that of the lubrication with liquid paraffin alone.