▎ 摘　　要

NOVELTY - The method comprises preparing a hydrophobic nanoparticle comprising graphite oxide, and stirring the hydrophobic nanoparticle with a hydrophilic solvent and then performing oxidation. The hydrophobic nanoparticle has a core-shell structure. A core of the nanoparticle comprises metal particles, metal oxide particles or semiconductor particles. The method further comprises swelling the hydrophobic nanoparticle comprising graphite oxide before the stirring step. The stirring step is carried out using a high pressure homogenizer or an ultrasonicator. USE - The method is useful for fabricating a graphene nanoparticle composite, which is useful for absorbing heavy metals (claimed) such as chromium and lead. ADVANTAGE - The method is capable of economically fabricating the graphene nanoparticle composite with controlled size and high yield. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: (1) a graphene nanoparticle composite; and (2) a method for removing heavy metals.