▎ 摘　　要

NOVELTY - A torsion angle double-layer graphene with direct growth on large area is prepared by growing carbon-soluble ferromagnetic metal film on insulating substrate, annealing and surface reduction treating molten carbon ferromagnetic metal film to obtain single crystal metal film, using single crystal metal film as metal catalytic substrate, putting single crystal metal film in chemical vapor deposition system, introducing inert gas and precursor gas containing carbon source, catalytically growing first layer of graphene on single crystal metal film at 800-900 degrees C, stopping introducing precursor gas containing carbon source, cooling at rate of 20-200 degrees C/minute, and utilizing mechanism of carbon re-precipitation in single crystal metal film, precipitating second layer of graphene with different twist angle from first layer of graphene between single crystal metal film and first layer of graphene. USE - The method is used for preparing torsion angle double-layer graphene with direct growth on large area for development of electronic devices and research of high temperature superconducting mechanism. ADVANTAGE - The method is convenient, has simple operation and low cost, and uses single crystal metal film with carbon dissolving ability as substrate and chemical vapor deposition method to control temperature on upper surface of first layer graphene.