▎ 摘　　要

NOVELTY - Preparing graphite quantum dot by sugar precursor at low temperature comprises (i) adding sugar monomer in alkaline aqueous solution, mixing uniformly, reacting at 50-100 degrees C for 0.5-12 hours under heating condition to obtain graphene quantum dot mother liquor, (ii) dialyzing the graphene quantum dot mother liquor obtained in the step (i) or filtering to remove impurities to obtain graphene quantum dot aqueous solution, and (iii) spray drying graphene quantum dot solution, freeze-drying or supercritical fluid drying to obtain graphene quantum dot powder. USE - The quantum dot is useful in biological imaging, dyeing, photocatalysis, photoelectric device. ADVANTAGE - The quantum dot is compounded with other materials, and produces multifunctional composite material.