▎ 摘　　要

NOVELTY - Preparing graphene nano belt by vapor etching carbon nano-tube, comprises introducing the multi-wall carbon nano-tube into a polytetrafluoroethylene lining, adding distilled water, oscillating the carbon nano-tube, dispersing uniformly, then placing the polytetrafluoroethylene lining into a reaction kettle, heating to 150-225 degrees C, reacting at constant temperature of 150-225 degrees C for 5-20 hours, and crack opening the multi-wall carbon nano-tube longitudinally to obtain graphene nano belt with high quality. USE - The method is useful for preparing graphene nano belt by vapor etching carbon nano-tube. ADVANTAGE - The method has simple preparation process, is easy to operate and can be completed in one step, does not require surfactant to disperse, and does not produce pollution, thus it is environmental friendly. The graphene nano belt is provided with less folds, is not easy to reunite, and has controllable number of layers and high yield.