Sulfur-Containing Carbon Nanospheres as Lubricant Additives for Antiwear and Friction Reduction

Herein, organic–inorganic hybrid sulfur-containing carbon nanospheres (SCNs) were successfully prepared by one-pot chemical oxidation polymerization of a thiophene monomer and then rigorous carbonization. On account of the good structural strength and organic phase derived from the precursor polythiophene, the as-prepared SCNs manifested remarkable oil-dispersing and tribological properties as lubricant nanoadditives. Subsequently, the friction mechanism of SCNs was deduced; the as-prepared SCNs had the capacity to take the shape of a strong protective film on the surface of friction pairs by intricate physical deposition and tribochemical reaction. So, the SCNs exhibited excellent tribological performance, including a high extreme pressure (950 N), an ultralow friction coefficient of less than 0.06, and a significant reduction in abrasion by 90%.