▎ 摘　　要

NOVELTY - Graphene/carbon quantum dot composite material comprises carbon quantum dot solution comprising 50-150 pts. wt. carbon source, 5-20 pts. wt. oxidant, 1-5 pts. wt. pH regulator, 350-450 pts. wt. solvent, and 0.1-1 pts. wt. dispersant, and graphene solid comprising 800-1200 pts. wt. graphite powder, 20-30 pts. wt. concentrated sulfuric acid, 1-5 pts. wt. concentrated nitric acid, 1-5 pts. wt. potassium permanganate, and 2-6 pts. wt. hydrogen peroxide. USE - The graphene/carbon quantum dot composite material is useful as cathode of lithium-ion battery. ADVANTAGE - The composite material can maintain good cycle stability and has high electrochemical activity. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparation method of the graphene/carbon quantum dot composite material.