▎ 摘　　要

NOVELTY - The device (10) has a reaction chamber (100) defining a space in which graphene is synthesized. A first counter electrode (111) is arranged inside the reaction chamber. A second counter electrode (112) is arranged inside the reaction chamber to face the first counter electrode. The N working electrodes (121-125) are arranged with a predetermined interval between the first counter electrode and the second counter electrode, where N is an integer of 2 or more. The first counter electrode is electrochemically connected to each of the N working electrodes. The second counter electrode is electrochemically connected to each of the N working electrodes, and the graphene is synthesized on the working electrode. The first counter electrode and the second counter electrode are independently of each other, a metal electrode or a graphite electrode. An electrolyte (130) inside the reaction chamber contains sulfate (SO42-), nitrate (NO3-), phosphate (PO43-), metal halide, and ionic liquids. USE - Graphene synthesis device used in production of nanometer-sized carbon materials. ADVANTAGE - The synthesis reaction of graphene occurs on both sides of the working electrode where graphene is synthesized since the graphene synthesis device includes two counter electrodes, so that the production rate and production can be increased. The process space required for synthesizing the same amount of graphene can be reduced, and the production rate and production speed can be increased, by increasing the number of working electrodes included in the device of the same size. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a graphene synthesis method used in production of nanometer-sized carbon materials. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic diagram showing the structure of a graphene synthesis device. Graphene synthesis device (10) Reaction chamber (100) First counter electrode (111) Second counter electrode (112) N working electrodes (121-125) Electrolyte (130)