▎ 摘　　要

NOVELTY - Producing graphene-carbon nanotube composite, comprises spraying and drying a mixed solution including graphene oxide, metal catalyst precursor, reducing agent and solvent to bind metal catalyst on the graphene, and (b) growing a carbon nanotube from the metal catalyst on the graphene. USE - The composite is useful as electrode material. ADVANTAGE - The composite has linear structure on surface of graphene, excellent specific surface area, large number of bonded carbon nanotubes, excellent electrical conductivity and electrostatic capacity, and enables morphology control process for improving the specific surface area of graphene. The method improves number of growing carbon nanotubes, is simple and economical, and reduces manpower and time. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for graphene-carbon nanotube composite comprising graphene flakes satisfying following formula such that L1/L2 is not greater than 0.5, where L2 is maximum long axis length of the graphene flake and L1 is maximum height of the graphene flake with respect to a direction perpendicular to the maximum long axis length, and carbon nanotubes bonded to the graphene flakes.