O.E. Glukhova – Dr.Sc.(Phys.-Math.), Professor, Head of Department of Radiotechnique and Electrodynamics,  Saratov State University named after N.G. Chernyshevsky

E-mail: GlukhovaOE@info.sgu.ru

V.V. Mitrofanov – Programmer, 

Department of Mathematical Modeling, Saratov State University named after N.G. Chernyshevsky E-mail: ip.boyar@gmail.com

M.M. Slepchenkov – Ph.D.(Phys.-Math.), Associate Professor, 

Department of Radiotechnique and Electrodynamics, Saratov State University named after N.G. Chernyshevsky

E-mail: slepchenkovm@mail.ru

This article is devoted to an investigation of deformation behavior and electrical conductivity of graphene-carbon nanotubes (CNTs) composite films under bending and stretching deformation by means of computational modeling. Using the original method of magnifying glass we built atomistic models of graphene/CNT composite films with various types of CNTs and inter-tube distance. Based on the results of calculations of the formation enthalpy, it was found that the models of mono- and bilayer films with CNTs (10,0) and (12,0) and an inter-tube distance of 10 and 12 hexagons will be the most energetically favorable. It has been established that the direction of deformation plays an important role in determining the deformation behavior of graphene/CNT composite film during bending. In the case of bending in the direction perpendicular to the CNTs, the composite film takes the form of an arc, and In the case of bending along the CNTs, the composite film exhibits the behavior characteristic of a beam subjected to bending deformation as a result of exposure to its free end of vertical force. The revealed regularities are valid both for mono- and bilayer films. With axial tension of the composite film, both in the direction of the CNTs and perpendicular to them, an elastic deformation was observed. At the same time, graphene/CNT films showed greater resistance to tensile deformation in the direction perpendicular to the CNTs. The results of the calculation of the distribution of local stresses of the atomic network of the composite films during bending and tensile deformations showed that the break of carbon bonds occurs when the magnitude of the stress on atoms is about 1.8 GPa. It is revealed that the electrical resistance of mono- and bilayer graphene/CNT composite films decreases with increasing bending. At the same time, the electrical resistance of a bilayer film is 1.5–2 times less than in a monolayer one. The lowest electrical resistance is observed for composite films with a CNT (12,0) of metallic conductivity.

1. Dang V.T., Nguyen D.D., Cao T.T. et al. Recent trends in preparation and application of carbon nanotube-graphene hybrid thin films // Adv. Nat. Sci: Nanosci. Nanotechnol. 2016. V. 7. P. 033002. DOI: 10.1088/2043-6262/7/3/033002.
2. Xia K., Zhan H., Gu Y. Graphene and Carbon Nanotube Hybrid Structure: A Review // Procedia IUTAM. 2017. V. 21. P. 94−101. DOI: 10.1016/j.piutam.2017.03.042.
3. Wang W., Ozkan M., Ozkan C.S. Ultrafast high energy supercapacitors based on pillared graphene nanostructures // J. Mater. Chem. A. 2016. V. 4. P. 3356−3361. DOI: 10.1039/C5TA07615C.
4. Tristán-López F., Morelos-Gómez A., Vega-Díaz S.M. et al. Large Area Films of Alternating Graphene-Carbon Nanotube Layers Processed in Water // ACS Nano. 2013. V. 7. P. 10788−10798. DOI: 10.1021/nn404022m.
5. Lv R., Cruz-Silva E., Terrones M. Building Complex Hybrid Carbon Architectures by Covalent Interconnections: Graphene-Nanotube Hybrids and More // ACS Nano. 2014. V. 8. P. 4061−4069. DOI: 10.1021/nn502426c.
6. Gan X., Lv R., Bai J. et al. Efficient photovoltaic conversion of graphene-carbon nanotube hybrid films grown from solid precursors // 2D Mater. 2015. V. 2. P. 034003. DOI: 10.1088/2053-1583/2/3/034003.
7. Su C.C., Chen T.X., Chang S.H. Compressive Strength Enhancement of Vertically Aligned Carbon Nanotube Forests by Constraint of Graphene Sheets // Materials. 2017. V. 10. P. 206. DOI: 10.3390/ma10020206.
8. Wang Y.C., Zhu Y.B., Wang F.C. et al. Super-elasticity and deformation mechanism of three-dimensional pillared graphene network structures // Carbon. 2017. V. 118. P. 588−596. DOI: 10.1016/j.carbon.2017.03.092.
9. Mitrofanov V.V., Slepchenkov M.M., Zhang G., Glukhova O.E. Hybrid carbon nanotube-graphene monolayer films: Regularities of structure, electronic and optical properties // Carbon. 2017. V. 115. P. 803−810. DOI: 10.1016/j.carbon.2017.01.040.
10. Liu A., Stuart S.J. Empirical bond-order potential for hydrocarbons: Adaptive treatment of van der Waals interactions // J. Comput. Chem. 2008. V. 29. P. 601−611 DOI: 10.1002/jcc.20817.
11. Elstner M. Gotthard Seifert Density functional tight binding // Phil. Trans. R. Soc. A. 2014. V. 372. P. 20120483. DOI: 10.1098/rsta.2012.0483.
12. Glukhova O.E., Slepchenkov M.M. Influence of the curvature of deformed graphene nanoribbons on their electronic and adsorptive properties: theoretical investigation based on the analysis of the local stress field for an atomic grid // Nanoscale. 2012. V. 11. P. 3335−3344. DOI: 10.1039/c2nr30477e.
13. Marder M.P. Condensed Matter Physics. Hoboken (New Jersey): John Wiley & Sons. Inc. 2011.
14. Aradi B., Hourahine B., Frauenheim Th. DFTB+, a Sparse Matrix-Based Implementation of the DFTB Method // J. Phys. Chem. A. 2007. V. 111. P. 5678−5684. DOI: 10.1021/jp070186p.
15. Glukhova O.E. Molecular Dynamics as the Tool for Investigation of Carbon Nanostructures Properties // Thermal Transport in CarbonBased Nanomaterials / Ed. Zhang G. Elsevier. 2017. P. 267−289. DOI: 10.1016/B978-0-32-346240-2.00010-8.