▎ 摘　　要

NOVELTY - Preparation of double-layer 30° torsion angle graphene monocrystalline wafer involves: providing a copper-nickel monocrystalline substrate, which has a thickness of 300-800 nm and nickel atom content of 15-22% of the total number of atoms; and adding the substrate to a chemical vapor deposition furnace, and annealing under gas atmosphere of argon and hydrogen in a ratio of (100-300 sccm):(5-15 sccm) and 1050-1100℃ to improve crystal quality, and growing under the atmosphere of argon, hydrogen and methane in a ratio of (100-300 sccm):(5-15 sccm):(0.025-0.5 sccm) and 1050-1100℃. Each layer of graphene of double-layer 30° torsion angle monocrystalline wafer is monocrystalline graphene, and the torsion angle between the double-layer graphenes is 30°. USE - Preparation of double-layer 30° torsion angle graphene monocrystalline wafer. ADVANTAGE - The method uses copper-nickel monocrystalline film as a substrate to obtain large-sized wafer-level double-layer 30° torsion angle graphene monocrystalline wafer by combining annealing and growing stages.