▎ 摘　　要

NOVELTY - A composition comprises filler and base fluid. The filler is carbon-coated metal and graphene-based two-dimensional nanosheet. The carbon-coated metal is carbon-coated aluminum and/or carbon-coated copper. The graphene-based two-dimensional nanosheet is selected from graphene, graphene oxide and/or modified graphene. USE - Composition for preparing thermally-conductive nanofluid (claimed). ADVANTAGE - The composition provides thermally-conductive nanofluid with excellent thermal conductivity and excellent stability. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of thermally-conductive nanofluid, which involves (S1) sequentially oxidizing carbon-coated metal and graphene-based two-dimensional nanosheet using oxidizing agent to obtain product (I), (S2) ultrasonically dispersing product (I) in the base liquid.