▎ 摘　　要

NOVELTY - Nano-lubricant composition having improved lubricant properties, comprises a lubricating fluid, and nitrogen-doped graphene which is dispersed in the fluid. The nitrogen-doped graphene is present at 0.125-5 mg/40 ml of the fluid. USE - The composition is useful for obtaining graphene sheets for various applications. ADVANTAGE - The composition: exhibits a coefficient of friction of 0.17-0.21 and a viscosity of 0.071-0.076 Pa.s, thus exhibiting improved lubricant properties (claimed) with reduced co-efficient of friction, surface temperature, wear and heat transfer properties; and is stable, keeps the operating temperature low and increases the machine life, while reducing the electrical power required to run the ID fan machine due to reduced friction coefficient, hence results in power savings and reduced operating costs of the machine. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing the nano-lubricant composition, comprising converting the natural graphite to graphite oxide, thermal exfoliation of the obtained graphite oxide to form thermal exfoliated-reduced graphene (TEG), negatively charging the TEG with anionic polyelectrolyte, dispersing the TEG, chemical polymerizing the dispersed product with polypyrrole, annealing at 800 degrees C in inert gas atmosphere and thus reducing the graphite oxide to nitrogen doped graphene, and dispersing the nitrogen-doped graphene in lubricating oil using probe sonication to form nano-lubricant.