▎ 摘　　要

NOVELTY - A graphene having at least one hole inside a ring-like structure formed by carbon and nitrogen or carbon and at least one element selected from Group 16 element and halogen. USE - In power storage device (claimed); e.g. display devices, lighting devices, desktop personal computers or laptop personal computers, image reproduction devices which reproduce a still image or a moving image stored in a recording medium such as a digital versatile disc (DVD), mobile phones, portable game machines, portable information terminals, e-book readers, cameras such as video cameras or digital still cameras, high-frequency heating apparatuses such as microwaves, electric rice cookers, electric washing machines, air-conditioning systems such as air conditioners, electric refrigerators, electric freezers, electric refrigerator-freezers, freezers for preserving DNA or dialysis devices, electric vehicles, hybrid vehicles which include both an internal-combustion engine and motor, motorized bicycles including motor-assisted bicycles, semiconductor display device such as a liquid crystal display device, a light-emitting device in which a light-emitting element such as an organic EL element is provided in each pixel, electrophoresis display device, digital micromirror device (DMD), plasma display panel (PDP), a field emission display (FED); for a material for a lithium-ion secondary battery. ADVANTAGE - The graphene has high conductivity and is permeable to ions of lithium; is used in power storage device with excellent charging and discharging characteristics; has a hole inside a ring-like structure formed by carbon and nitrogen has conductivity and is permeable to ions of lithium. The graphene or a stack of graphene has high conductivity and is permeable to ions of lithium. The graphene is used in electric device which has high reliability and can withstand long-term or repeated use. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) a stack of graphene having at least one hole inside a ring-like structure formed by carbon and nitrogen or carbon and at least one element selected from Group 16 element and halogen; and (2) a power storage device comprising the graphene.