1
|
Aparicio E, Tangarife E, Munoz F, Gonzalez RI, Valencia FJ, Careglio C, Bringa EM. Simulated mechanical properties of finite-size graphene nanoribbons. NANOTECHNOLOGY 2021; 32:045709. [PMID: 33045683 DOI: 10.1088/1361-6528/abc036] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
There are many simulation studies of mechanical properties of graphene nanoribbons (GNR), but there is a lack of agreement regarding elastic and plastic behavior. In this paper we aim to analyze mechanical properties of finite-size GNR, including elastic modulus and fracture, as a function of ribbon size. We present classical molecular dynamics simulations for three different empirical potentials which are often used for graphene simulations: AIREBO, REBO-scr and REAXFF. Ribbons with and without H-passivation at the borders are considered, and the effects of strain rate and different boundaries are also explored. We focus on zig-zag GNR, but also include some armchair GNR examples. Results are strongly dependent on the empirical potential employed. Elastic modulus under uniaxial tension can depend on ribbon size, unlike predictions from continuum-scale models and from some atomistic simulations, and fracture strain and progress vary significantly amongst the simulated potentials. Because of that, we have also carried out quasi-static ab-initio simulations for a selected size, and find that the fracture process is not sudden, instead the wave function changes from Blöch states to a strong interaction between localized waves, which decreases continuously with distance. All potentials show good agreement with DFT in the linear elastic regime, but only the REBO-scr potential shows reasonable agreement with DFT both in the nonlinear elastic and fracture regimes. This would allow more reliable simulations of GNRs and GNR-based nanostructures, to help interpreting experimental results and for future technological applications.
Collapse
Affiliation(s)
- E Aparicio
- CONICET and Universidad de Mendoza, Mendoza, 5500, Argentina
| | - E Tangarife
- Centro de Nanotecnología Aplicada, Facultad de Ciencias, Universidad Mayor, Santiago 8580745, Chile
| | - F Munoz
- Departamento de Física, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
- Centro para el Desarrollo de la Nanociencia y la Nanotecnología, CEDENNA, Santiago, Chile
| | - R I Gonzalez
- Centro de Nanotecnología Aplicada, Facultad de Ciencias, Universidad Mayor, Santiago 8580745, Chile
- Centro para el Desarrollo de la Nanociencia y la Nanotecnología, CEDENNA, Santiago, Chile
| | - F J Valencia
- Centro para el Desarrollo de la Nanociencia y la Nanotecnología, CEDENNA, Santiago, Chile
- Centro de Investigación DAiTA Lab, Facultad de Estudios Interdisciplinarios, Universidad Mayor, Chile
| | - C Careglio
- Universidad Nacional de Cuyo, Facultad de Ingeniería, Mendoza, 5500, Argentina
| | - E M Bringa
- CONICET and Universidad de Mendoza, Mendoza, 5500, Argentina
- Centro de Nanotecnología Aplicada, Facultad de Ciencias, Universidad Mayor, Santiago 8580745, Chile
| |
Collapse
|
2
|
Chen S, Wang Y, Yang L, Karouta F, Sun K. Electron-Induced Perpendicular Graphene Sheets Embedded Porous Carbon Film for Flexible Touch Sensors. NANO-MICRO LETTERS 2020; 12:136. [PMID: 34138121 PMCID: PMC7770710 DOI: 10.1007/s40820-020-00480-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 06/04/2020] [Indexed: 05/21/2023]
Abstract
Graphene-based materials on wearable electronics and bendable displays have received considerable attention for the mechanical flexibility, superior electrical conductivity, and high surface area, which are proved to be one of the most promising candidates of stretching and wearable sensors. However, polarized electric charges need to overcome the barrier of graphene sheets to cross over flakes to penetrate into the electrode, as the graphene planes are usually parallel to the electrode surface. By introducing electron-induced perpendicular graphene (EIPG) electrodes incorporated with a stretchable dielectric layer, a flexible and stretchable touch sensor with "in-sheet-charges-transportation" is developed to lower the resistance of carrier movement. The electrode was fabricated with porous nanostructured architecture design to enable wider variety of dielectric constants of only 50-μm-thick Ecoflex layer, leading to fast response time of only 66 ms, as well as high sensitivities of 0.13 kPa-1 below 0.1 kPa and 4.41 MPa-1 above 10 kPa, respectively. Moreover, the capacitance-decrease phenomenon of capacitive sensor is explored to exhibit an object recognition function in one pixel without any other integrated sensor. This not only suggests promising applications of the EIPG electrode in flexible touch sensors but also provides a strategy for internet of things security functions.
Collapse
Affiliation(s)
- Sicheng Chen
- Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System, Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China
| | - Yunfei Wang
- Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System, Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China
| | - Lei Yang
- Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System, Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China.
| | - Fouad Karouta
- Research School of Physics, The Australian National University, Canberra, ACT, 2601, Australia
| | - Kun Sun
- Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System, Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China
| |
Collapse
|