▎ 摘　　要

NOVELTY - Lubricating additive of composite carbon material comprises sequentially from inside to outside: nano-diamond layer, polydopamine layer and graphene oxide layer, which has spherical structure, where the polydopamine layer coats the nano-diamond layer and the graphene oxide layer coats the polydopamine layer; or nano-diamond layer, polydopamine layer, graphene layer, and polydopamine layer, where the polydopamine coats the nano-diamond layer, the graphene layer coats the polydopamine layer, and the polydopamine coats the graphene layer. USE - The lubricating additive of composite carbon material is used for super-lubricating water lubricant useful for mechanical parts used in atmospheric environment (all claimed). ADVANTAGE - The additive provides super-lubricating water lubricant having friction factor, which reaches 0.003. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: (1) preparation of the lubricating additive of composite carbon material comprising mixing dopamine hydrochloride solution, water, and tris(hydroxymethyl)aminomethane (Tris) solution, adding hydrochloric acid (HCl) solution to adjust the pH, adding nano-diamond colloid aqueous solution, and reacting to obtain polydopamine coated nano-diamond composite material; adding into graphene oxide solution, reacting to obtain graphene oxide/polydopamine/nano-diamond composite material; or sequentially repeating the first step and second step, and subjecting the reaction mixture obtained to centrifugal separation, removing the supernatant, and freeze drying to obtain lubricating additive, where the volume ratio and amount of dopamine hydrochloride, water, Tris solution, and HCl solution participating in the reaction in the third step are the same as those in the first step, and the addition amount and the concentration of graphene oxide solution participating in the reaction are the same as in the second step; (2) super-lubricating water lubricant comprising water and lubricating additive; and (3) preparation of the super-lubricating water lubricant comprising mixing the lubricating additive and water.