▎ 摘　　要

We describe a clean method of graphene nanoribbon (GNR) extraction from multiwall carbon nanotubes (MWNTs), performed in a high vacuum, nonchemical environment. Electrical current and nanomanipulation are used to unwrap a portion of the MWNT and thus produce a GNR of desired width and length. The unwrapping method allows GNRs to be concurrently characterized structurally via high-resolution transmission electron microscopy (TEM) and evaluated for electrical transport, including situations for which the GNR is severely mechanically flexed. High quality GNRs have exceptional current-carrying capacity, comparable to the exfoliated graphene.