▎ 摘　　要

There remains a common and critical challenge in the preparation of carbon nanotube (CNT) composite materials, i.e., random dispersion of CNTs in the second phase. Here we have reported a general method to prepare perpendicularly aligned CNT/olefin composite films through a conventional slicing technique. The thickness of a composite film can be accurately controlled from about fifty nanometers to fifty micrometers, and the diameter and density of CNTs may be varied in a wide range as required. In particular, due to the generated defect at the end during the slicing process, the separated CNTs from the composite film have been easily unzipped to produce graphenes in the forms of nanoribbons and nanosheets with a yield of almost 100% under ultrasonic treatment.