The tribological properties of diethylammonium lanthanide tetrakis (diethyldithiocarbamate) in lubricating oil

The synthesis of four oil-soluble rare earth complexes of diethylammonium lanthanide tetrakis(diethyldithiocarbamate) (ReDTC) is described. The tribological properties of these rare earth complexes as additives in lubricating oil have been evaluated using a four-ball machine. The results show that these novel complexes have excellent extreme-pressure properties and selective antiwear properties in lubricating oil. The action mechanism of the rare earth complexes as additives in lubricating oil was investigated using X-ray photoelectron spectroscopy (XPS).