▎ 摘　　要

Graphene is a one-atom thick carbon sheet with unique combination of physical and mechanical properties promising for many applications. Bending rigidity of graphene is very small and that is why weak van der Waals forces can create secondary structures such as folds, scrolls, etc. Recently the authors offered a model of a chain with particles moving in a plane to simulate properties of such secondary structures. In the present work the model is modified to enable the study of structure and properties of graphene nanoribbon scrolls (GNS) around carbon nanotubes (CNT). With the help of this model possible equilibrium structures are found and their energies are compared. Particularly it is shown that relatively short graphene nanoribbons wrap CNT without a cavity, producing a dense structure. For nanoribbons with larger length there always appears a cavity between GNS and CNT. Then the temperature effect on the GNS-CNT complex is studied. It is found that the dense complexes at elevated temperatures undergo a phase transition to the states with a cavity. This transition is characterized by a sharp increase in the outer radius of GNS. This finding opens a way to design materials with a huge thermal expansion coefficient in a specific temperature range as well as temperature sensors with a great sensitivity. (C) 2017 Elsevier B.V. All rights reserved.