▎ 摘　　要

NOVELTY - Preparation of single-layer graphene folded structure with controllable twist angle involves forming (i) interface between substrate and single-layer graphene, placing (ii) single-layer graphene sample on sample stage of atomic force microscope, finding (iii) sharp corner of the single-layer graphene profile and position the probe of the atomic force microscope to the sharp corner and tip of the probe is a silicon dioxide microsphere tip having diameter of 0.5-10 mu m and positioning unit which is the distance from the apex of the fingertip corner to the centerline of the probe, increasing (iv) the relative humidity of the humidity sensing chamber of the atomic force microscope to a predetermined value, lowering (v) the needle until stable meniscus is formed between the probe and the single-layer graphene, moving (vi) the probe towards the component of single-layer graphene with speed of 0.5 mu m/second or less and lifting (vii) the needle after moving to predetermined position. USE - Preparation of single-layer graphene folded structure with controllable twist angle used for optoelectronic devices and quantum devices. ADVANTAGE - The method enables simple preparation of single-layer graphene folded structure with controllable twist angle without a harsh operating environment, and can flexibly and accurately control the torsion angle. DETAILED DESCRIPTION - Preparation of single-layer graphene folded structure with controllable twist angle involves forming (i) interface water between substrate and single-layer graphene supported on substrate, placing (ii) single-layer graphene sample on sample stage of atomic force microscope, finding (iii) sharp corner of the single-layer graphene profile and position the probe of the atomic force microscope to the sharp corner and tip of the probe is a silicon dioxide microsphere tip having diameter of 0.5-10 mu m and diameter of the microspheres does not exceed 1/2 of the largest dimension on the graphene along the direction of the pseudo-folding movement and positioning unit which is the distance from the apex of the fingertip corner to the centerline of the probe is less than or equal to the radius of curvature of the microsphere of the needle tip, increasing (iv) the relative humidity of the humidity sensing chamber of the atomic force microscope to a predetermined value, lowering (v) the needle with a load of 5-20 nN and keep it until a stable meniscus is formed between the probe and the single-layer graphene, moving (vi) the probe towards the component of single-layer graphene with moving speed of 0.5 mu m/second or less and lifting (vii) the needle after moving to predetermined position.