title: In-Situ Stretching Patterned Graphene Nanoribbons in the Transmission Electron Microscope.
abstract: The mechanical response of patterned graphene nanoribbons (GNRs) with a width less than 100 nm was studied in-situ using quantitative tensile testing in a transmission electron microscope (TEM). A high degree of crystallinity was confirmed for patterned nanoribbons before and after the in-situ experiment by selected area electron diffraction (SAED) patterns. However, the maximum local true strain of the nanoribbons was determined to be only about 3%. The simultaneously recorded low-loss electron energy loss spectrum (EELS) on the stretched nanoribbons did not reveal any bandgap opening. Density Functional Based Tight Binding (DFTB) simulation was conducted to predict a feasible bandgap opening as a function of width in GNRs at low strain. The bandgap of unstrained armchair graphene nanoribbons (AGNRs) vanished for a width of about 14.75 nm, and this critical width was reduced to 11.21 nm for a strain level of 2.2%. The measured low tensile failure strain may limit the practical capability of tuning the bandgap of patterned graphene nanostructures by strain engineering, and therefore, it should be considered in bandgap design for graphene-based electronic devices by strain engineering.
authors.affiliation: Fraunhofer Institute for Ceramic Technologies and Systems (IKTS), 01109, Dresden, Germany. Zhongquan.liao@ikts.fraunhofer.de.|Institute for Materials Science and Max Bergmann Center of Biomaterials, Technische Universität Dresden, 01069, Dresden, Germany. Zhongquan.liao@ikts.fraunhofer.de.|Center for Advancing Electronics Dresden (cfaed), Technische Universität Dresden, 01062, Dresden, Germany. Zhongquan.liao@ikts.fraunhofer.de.
authors.forename: Zhongquan
authors.initials: Z
authors.lastname: Liao
authors.affiliation: Institute for Materials Science and Max Bergmann Center of Biomaterials, Technische Universität Dresden, 01069, Dresden, Germany.|Max Planck Institute for the Physics of Complex Systems, 01187, Dresden, Germany.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Medrano Sandonas
authors.affiliation: Professur für Makromolekulare Chemie, Department Chemie, Technische Universität Dresden, 01069, Dresden, Germany.
authors.forename: Tao
authors.initials: T
authors.lastname: Zhang
authors.affiliation: Fraunhofer Institute for Ceramic Technologies and Systems (IKTS), 01109, Dresden, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Gall
authors.affiliation: Institute for Materials Science and Max Bergmann Center of Biomaterials, Technische Universität Dresden, 01069, Dresden, Germany.
authors.forename: Arezoo
authors.initials: A
authors.lastname: Dianat
authors.affiliation: Institute for Materials Science and Max Bergmann Center of Biomaterials, Technische Universität Dresden, 01069, Dresden, Germany.
authors.forename: Rafael
authors.initials: R
authors.lastname: Gutierrez
authors.affiliation: Fraunhofer Institute for Ceramic Technologies and Systems (IKTS), 01109, Dresden, Germany.
authors.forename: Uwe
authors.initials: U
authors.lastname: Mühle
authors.affiliation: Fraunhofer Institute for Ceramic Technologies and Systems (IKTS), 01109, Dresden, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Gluch
authors.affiliation: Professur für Makromolekulare Chemie, Department Chemie, Technische Universität Dresden, 01069, Dresden, Germany.
authors.forename: Rainer
authors.initials: R
authors.lastname: Jordan
authors.affiliation: Institute for Materials Science and Max Bergmann Center of Biomaterials, Technische Universität Dresden, 01069, Dresden, Germany.|Center for Advancing Electronics Dresden (cfaed), Technische Universität Dresden, 01062, Dresden, Germany.|Dresden Center for Computational Materials Science, TU Dresden, 01062, Dresden, Germany.
authors.forename: Gianaurelio
authors.identifier: 0000-0002-6574-7848
authors.initials: G
authors.lastname: Cuniberti
authors.affiliation: Fraunhofer Institute for Ceramic Technologies and Systems (IKTS), 01109, Dresden, Germany.|Center for Advancing Electronics Dresden (cfaed), Technische Universität Dresden, 01062, Dresden, Germany.
authors.forename: Ehrenfried
authors.initials: E
authors.lastname: Zschech