▎ 摘　　要

NOVELTY - Oleic acid is added to ethanol solution, to obtain solution (a). A cobalt salt and a precipitant are added to solution (a) and stirred, to obtain solution (b). Graphene oxide is added to solution (b) and stirred, to obtain suspension (c). The suspension (c) is ultrasonically processed, and homogeneously hydrothermally reacted, to obtain precipitate. The precipitate is separated, washed and dried, to obtain three-dimensional cobalt carbonate quantum dot-coated graphene composite electrode material. USE - One-step solvothermal synthesis of three-dimensional cobalt carbonate quantum dot-coated graphene composite electrode material (claimed). ADVANTAGE - The method provides three-dimensional cobalt carbonate quantum dot-coated graphene composite electrode material with excellent mechanical strength, stability, charging and discharging characteristics and electrochemical characteristics. DETAILED DESCRIPTION - Oleic acid is added to ethanol solution such that the volume ratio of oleic acid and ethanol solution is (0.5-3):70, to obtain solution (a). A cobalt salt and a precipitant are added to solution (a) and stirred, to obtain solution (b). The volume ratio of cobalt salt and ethanol solution is (2-6) mmol:70 mL. Graphene oxide is added to solution (b) and stirred, to obtain suspension (c). The volume ratio of graphene oxide and ethanol solution is (0.07-0.14) g:70 mL. The suspension (c) is ultrasonically processed, and homogeneously hydrothermally reacted, to obtain precipitate. The precipitate is separated, washed and dried, to obtain three-dimensional cobalt carbonate quantum dot-coated graphene composite electrode material.