▎ 摘　　要

NOVELTY - Multiatom co-doped quantum dot is graphene quantum dot simultaneously doped with nitrogen atoms and halogen atoms. USE - Multiatom co-doped quantum dot used in contrast agent composition (claimed) used in electrochemical energy devices in cell and in vivo imaging studies. ADVANTAGE - The multiatom co-doped quantum dot has excellent electrochemical activity against redox reaction by improving content of nitrogen relative to conventional method, high fluorescence quantum yield due to conjugation of a non-covalent electron pair of nitrogen atom and halogen atom, excellent dispersing power in an aqueous environment without showing toxicity in vivo. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing multiatom co-doped quantum dot, which involves doping nitrogen atom and halogen atom simultaneously by hydrothermal reaction of a mixture containing a saccharide compound, a nitrogen precursor and a halide precursor.