Design and Analysis of Electrostatically Actuated Mechanical Sensor for Graphene

2018 ◽  
Author(s):  
Ayse Tekes ◽  
Jungkyu Park
Keyword(s):  
Single Layer ◽  
Single Layer Graphene ◽  
Element Analysis ◽  
Lumped Model ◽  
Electrostatically Actuated ◽  
Strain Behavior ◽  
Mems Device ◽  
In Situ Detection ◽  
Nanostructured Sample

Very little is known about the fracture behaviors of novel nanomaterials such as carbon nanotubes and graphene due to the difficulty of sample manipulation and in situ detection of their failure mechanism. In the present study, the design and analysis of a Microelectromechanical System (MEMs) device is presented for the tensile testing of single layer graphene. The electrostatically actuated dual parallel plate actuators in the proposed MEMS device enable in situ measurement in a scanning electron microscope by stretching the two ends of a nanostructured sample simultaneously. The elongation in the specimen is obtained by nonlinear finite element analysis using COMSOL, and MATLAB. For the validation of the proposed MEMS device, a lumped model of the system is utilized to analyze the stress-strain behavior of the nanostructured sample under the force generated by the electrodes.

scholarly journals Millisecond lattice gasification for high-density CO2- and O2-sieving nanopores in single-layer graphene

2021 ◽  
Vol 7 (9) ◽  
pp. eabf0116
Author(s):  
Shiqi Huang ◽  
Shaoxian Li ◽  
Luis Francisco Villalobos ◽  
Mostapha Dakhchoune ◽  
Marina Micari ◽  
...  
Keyword(s):  
Single Layer ◽  
High Density ◽  
Single Layer Graphene ◽  
Pore Density ◽  
Vacancy Defects ◽  
Carbon Gasification ◽  
Layer Graphene ◽  
Gas Molecules ◽  
Good Agreement

Etching single-layer graphene to incorporate a high pore density with sub-angstrom precision in molecular differentiation is critical to realize the promising high-flux separation of similar-sized gas molecules, e.g., CO2 from N2. However, rapid etching kinetics needed to achieve the high pore density is challenging to control for such precision. Here, we report a millisecond carbon gasification chemistry incorporating high density (>1012 cm−2) of functional oxygen clusters that then evolve in CO2-sieving vacancy defects under controlled and predictable gasification conditions. A statistical distribution of nanopore lattice isomers is observed, in good agreement with the theoretical solution to the isomer cataloging problem. The gasification technique is scalable, and a centimeter-scale membrane is demonstrated. Last, molecular cutoff could be adjusted by 0.1 Å by in situ expansion of the vacancy defects in an O2 atmosphere. Large CO2 and O2 permeances (>10,000 and 1000 GPU, respectively) are demonstrated accompanying attractive CO2/N2 and O2/N2 selectivities.

scholarly journals Geometrical Dimensional Effect on Natural Frequency of Single Layer Graphene in Armchair Configuration

2021 ◽  
Vol 4 (2) ◽  
Author(s):  
Harshad Patel
Keyword(s):  
Graphene Sheet ◽  
Plate Theory ◽  
Single Layer ◽  
Free Edge ◽  
Single Layer Graphene ◽  
Geometrical Parameters ◽  
Classical Plate Theory ◽  
Element Analysis ◽  
Nanomechanical Resonator ◽  
Layer Graphene

Graphene has remarkable strength, such as yield strength and elasticconstant. The dynamic behaviour of graphene sheet is affected bygeometrical variation in atomic arrangement. This paper introducedgraphene with armchair atomic structure for estimating fundamental naturalfrequencies. The presented analysis can be useful for the possible highfrequency nanomechanical resonator systems. The analytical formulation,based on classical plate theory and continuum solid modelling based finiteelement method have been performed for estimation of fundamental naturalfrequencies of single layer graphene sheet (SGLS) with different boundaryconditions. The free edge and clamped edge boundary conditions have beenconsidered. For simplifying analytical formulations, Blevins approach fordynamic solution has been adopted and for validating analytical results.The finite element analysis of SLGS has been performed using ANSYSsoftware. The effect of variation in geometrical parameters in terms ofwidth and length of SLGS has been analysed for realization of ultra-highfrequency based nanomechanical resonator systems

scholarly journals In situ probing of the crystallization kinetics of rr-P3HT on single layer graphene as a function of temperature

2017 ◽  
Vol 19 (12) ◽  
pp. 8496-8503 ◽  
Author(s):  
Nicolas Boulanger ◽  
Victor Yu ◽  
Michael Hilke ◽  
Michael F. Toney ◽  
David R. Barbero
Keyword(s):  
Diffraction Analysis ◽  
Crystallization Kinetics ◽  
Single Layer ◽  
Single Layer Graphene ◽  
X Ray Diffraction ◽  
X Ray ◽  
Layer Graphene ◽  
Kinetics Of

In situ X-ray diffraction analysis of P3HT films during cooling down on both Si and G.

scholarly journals In-situ measurement of the heat transport in defect- engineered free-standing single-layer graphene

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Haidong Wang ◽  
Kosaku Kurata ◽  
Takanobu Fukunaga ◽  
Hiroshi Takamatsu ◽  
Xing Zhang ◽  
...  
Keyword(s):  
Heat Transport ◽  
Single Layer ◽  
In Situ Measurement ◽  
Single Layer Graphene ◽  
Free Standing ◽  
Layer Graphene

Preparation of High-Quality Graphene by Sodium Borohydride Reducing Stage-1 FeCl3-GIC via In Situ Hydrogen Exfoliation

2017 ◽  
Vol 744 ◽  
pp. 458-462
Author(s):  
Xu Qiao ◽  
Zhi Lin ◽  
Yuan Yuan Si ◽  
Xiao Dan Lin ◽  
Shao Wei Cui ◽  
...  
Keyword(s):  
Sodium Borohydride ◽  
Single Layer ◽  
Single Layer Graphene ◽  
High Quality ◽  
Force Microscopy ◽  
Sem Image ◽  
Exfoliated Graphene ◽  
Atomic Force ◽  
Stage 1

High-quality graphene is prepared via In Situ hydrogen exfoliation of the reaction of stage-1 FeCl3-GIC with sodium borohydride solution, followed by washings and sonication. The hydrogen evolved from the borohydride exfoliates the GIC and reduces defect structure in the graphene simultaneously, make it more conjugated. Raman spectrum results show the intensity ratio of the D and G peak is about 0.09, even smaller than that of the original graphite, which is 0.17. The only C1s peak locating at 284.9 eV in another way supports the only one structure in the graphene. SEM image of exfoliated graphene Fig. 2(f) shows that the graphene obtained has curly morphology, which is significantly different from graphite flakes. TEM of the graphene shows a single layer graphene and its overlap with other graphene. Atomic force microscopy (AFM) measure shows that the average thickness of graphene sheets is about 0.530 nm. Proving that the high quality graphene prepared is chiefly single layer. After compression molded into graphene mat, its conductivity reaches 2.85×105S/m, which is about one third of the theoretical value of graphene. This method is promising for mass production of high-quality graphene.

scholarly journals In Situ Detection of Active Edge Sites in Single-Layer MoS2 Catalysts

ACS Nano ◽  
2015 ◽  
Vol 9 (9) ◽  
pp. 9322-9330 ◽  
Author(s):  
Albert Bruix ◽  
Henrik Gøbel Füchtbauer ◽  
Anders K. Tuxen ◽  
Alexander S. Walton ◽  
Mie Andersen ◽  
...  
Keyword(s):  
Single Layer ◽  
Active Edge ◽  
Mos2 Catalysts ◽  
In Situ Detection

scholarly journals Gently Does It!: In Situ Preparation of Alkali Metal - Solid Electrolyte Interfaces for Photoelectron Spectroscopy

2021 ◽  
Author(s):  
Joshua Gibson ◽  
Sudarshan Narayanan ◽  
Jack Swallow ◽  
Pardeep Kumar-Thakur ◽  
Mauro Pasta ◽  
...  
Keyword(s):  
Alkali Metal ◽  
Photoelectron Spectroscopy ◽  
Alkali Metals ◽  
Organic Liquid ◽  
Single Layer ◽  
Metal Deposition ◽  
Single Layer Graphene ◽  
Energy Storage Devices ◽  
Electrolyte Interface

The key charge transfer processes in energy storage devices occur at the electrode-electrolyte interface, which is typically buried making it challenging to access the interfacial chemistry. In the case of Li-ion batteries, metallic Li electrodes hold promise for increasing energy and power densities, and when used in conjunction with solid electrolytes (SEs) adverse safety implications associated with dendrite formation in organic liquid electrolytes can potentially be overcome. To better understand the stability of SEs when in contact with alkali metals and the reactions that occur, here we consider the deposition of thin (~10 nm) alkali metal films onto SE surfaces, that are thin enough that X-ray photoelectron spectroscopy can probe the buried electrode-electrolyte interface. We highlight the importance of in situ alkali metal deposition, by assessing the contaminant species that are present after glovebox handling and the use of ‘inert’ transfer devices. Consequently, we compare and contrast three available methods for in situ alkali-metal deposition; Li sputter deposition, Li evaporation, and Li plating induced by e− flood-gun irradiation. Studies on both a sulphide SE (Li6PS5Cl), and a single-layer graphene probe surface reveal that the more energetic Li deposition methods, such as sputtering, can induce surface damage and interfacial mixing that is not seen with thermal evaporation. This indicates that appropriate selection of the Li deposition method for in situ studies is required to observe representative behaviour, and the results of previous studies involving energetic deposition may warrant further evaluation.

Sign in / Sign up

Export Citation Format

Share Document