Simulation Studies on the Interaction of Graphene and Gold Nanoparticle

2018 ◽  
Vol 17 (03) ◽  
pp. 1760043
Author(s):  
J. Meena Devi
Keyword(s):  
Gold Nanoparticle ◽  
Room Temperature ◽  
Md Simulation ◽  
Computational Study ◽  
Single Layer ◽  
Hybrid Nanostructures ◽  
Single Layer Graphene ◽  
Simulation Studies ◽  
Different Types ◽  
Alkane Thiol

In this computational study, the interaction between a single layer graphene sheet and a gold nanoparticle is investigated employing molecular dynamics (MD) simulation at room temperature. The interactions between the graphene and gold nanoparticle were explored for three different types of gold nanoparticle, namely, bare gold nanoparticle, methyl terminated alkane thiol-coated gold nanoparticle and hydroxy terminated alkane thiol-coated gold nanoparticle. The interactions between the graphene and gold nanoparticle have resulted in the adsorption of gold nanoparticle on the surface of graphene. The structural properties of the graphene–gold hybrid nanostructures were found to be influenced by the capping layer of the gold nanoparticle.

Electrochemical Epitaxial (200) PbSe submicron-plates on Single-Layer Graphene for Ultrafast Infrared Response

2021 ◽  
Author(s):  
Chan Yang ◽  
Shuanglong Feng ◽  
Yinye Yu ◽  
Jun Shen ◽  
Xingzhan Wei ◽  
...  
Keyword(s):  
Room Temperature ◽  
Single Layer ◽  
Infrared Detection ◽  
Single Layer Graphene ◽  
Robust Detection ◽  
Layer Graphene ◽  
Highly Efficient ◽  
Low Visibility ◽  
Ultrafast Infrared

Highly efficient near and medium-wave infrared detection at room temperature is considered one of the most intensive studies due to their robust detection in foggy weather or other low visibility...

scholarly journals Graphene on SiC(0001) inspected by dynamic atomic force microscopy at room temperature

2015 ◽  
Vol 6 ◽  
pp. 901-906 ◽  
Author(s):  
Mykola Telychko ◽  
Jan Berger ◽  
Zsolt Majzik ◽  
Pavel Jelínek ◽  
Martin Švec
Keyword(s):  
Electron Scattering ◽  
Room Temperature ◽  
Single Layer ◽  
Tunneling Current ◽  
Single Layer Graphene ◽  
Force Microscopy ◽  
Atomic Force ◽  
Scattering Effects ◽  
Out Of Plane ◽  
Theoretical Simulations

We investigated single-layer graphene on SiC(0001) by atomic force and tunneling current microscopy, to separate the topographic and electronic contributions from the overall landscape. The analysis revealed that the roughness evaluated from the atomic force maps is very low, in accord with theoretical simulations. We also observed that characteristic electron scattering effects on graphene edges and defects are not accompanied by any out-of-plane relaxations of carbon atoms.

scholarly journals Probable Cause for the Superconductor-Like Properties of Alkane-Wetted Graphite and Single-Layer Graphene above Room Temperature under Ambient Pressure

2018 ◽  
Author(s):  
Myung-Hwan Whangbo
Keyword(s):  
Fermi Surface ◽  
Acoustic Phonon ◽  
Room Temperature ◽  
Ambient Pressure ◽  
Strong Support ◽  
Single Layer ◽  
Single Layer Graphene ◽  
Strong Electron ◽  
Layer Graphene ◽  
Fermi Surface Nesting

Recently Kawashima has reported that, when wetted with alkanes, several forms of graphite and single-layer graphene exhibit superconductor-like properties above room temperature under ambient pressure [AIP Adv. 2013, 3, 052132; arXiv:1612.05294; arXiv:1801.09376]. Under the assumption that these seemingly unlikely properties arise from the presence of paired electrons brought about by the alkane-wetting, we explored their implications to arrive at a probable mechanism for strong electron-pairing driven by Fermi surface nesting and acoustic phonon. This mechanism explains why alkane-wetting is essential for the graphene systems to become “superconductor-like” above room temperature and why the “Tc” of alkane-wetted pitch-based graphite fibers increases almost linearly from ~363 to ~504 K with increasing the molecular weight of alkane from heptane to hexadecane. It also provides a number of experimentally-verifiable predictions, the confirmation of which will provide a strong support for the superconductivity driven by Fermi surface nesting and acoustic phonon.

scholarly journals Probable Cause for the Superconductor‐like Properties of Alkane-wetted Graphite and Single-layer Graphene Above Room Temperature Under Ambient Pressure

2018 ◽  
Author(s):  
mike whangbo
Keyword(s):  
Fermi Surface ◽  
Acoustic Phonon ◽  
Room Temperature ◽  
Ambient Pressure ◽  
Strong Support ◽  
Single Layer ◽  
Single Layer Graphene ◽  
Layer Graphene ◽  
Fermi Surface Nesting ◽  
Graphite Fibers

<div>Recently Kawashima has reported that, when wetted with alkanes, several forms of graphite and single‐layer graphene exhibit superconductor‐like properties above room temperature under ambient pressure [AIP Adv. 2013, 3, 052132; arXiv:1612.05294; arXiv:1801.09376]. Under the assumption that these seemingly unlikely properties arise from the presence of paired electrons brought about by the</div><div>alkane‐wetting, we explored their implications to arrive at a probable mechanism for strong electronpairing</div><div>driven by Fermi surface nesting and acoustic phonon. This mechanism explains why alkane‐wetting is essential for the graphene systems to become “superconductor‐like” above room temperature and why the “Tc” of alkane‐wetted pitch‐based graphite fibers increases almost linearly from ~363 to ~504 K with increasing the molecular weight of alkane from heptane to hexadecane. It also provides a number of</div><div>experimentally‐verifiable predictions, the confirmation of which will provide a strong support for the superconductivity driven by Fermi surface nesting and acoustic phonon.</div>

A Study on the Tip-Based Nanomachining of Silicon Wafer Using Atomic Force Microscopy (AFM)

2020 ◽  
Author(s):  
Chionye Okwuashi ◽  
J. Ma ◽  
M. P. Jahan
Keyword(s):  
Silicon Wafer ◽  
Silicon Substrate ◽  
Room Temperature ◽  
Md Simulation ◽  
Crystalline Silicon ◽  
Lattice Structure ◽  
Computational Study ◽  
Md Simulations ◽  
Simulation Software ◽  
Fixed Layer

Abstract In this work, the principles of nanoindentation and nanoscratching processes (tip-based nanomachining processes) are applied in the computational study of relevant material behaviors of single crystalline silicon wafer. Molecular dynamics (MD) simulations are carried out to model the tip-based nanomachining process of a silicon substrate by employing LAMMPS, a free MD simulation software. A spherical diamond tool tip with a radius of 8Å is considered. In the MD simulation, a single diamond indenter is treated as a rigid body. The dimensions of the silicon workpiece in the MD simulations are 500Å × 500Å × 350Å, containing 2,207,698 Si atoms. A diamond cubic lattice structure is employed to arrange these Si atoms from the very beginning at 293 K (room temperature) and a lattice constant of 5.43Å is employed. The lowest layer of the Si workpiece model is fixed and this fixed layer is one atom thick i.e. its thickness is 5.43Å. Immediately above the fixed layer is another layer of equal thickness (5.43Å), which is called thermostat layer. This layer serves the purpose of maintaining constant temperature of the system. The force-controlled approach is employed for this study. Essentially, this research evaluates the influence of three parameters: exerted force on indenter, workpiece temperature (room temperature and several higher workpiece temperatures), and indenter size on the depth of indentation, length of scratch, and coordination number of the atoms. Verlet -Velocity algorithm is used to compute the velocities and positions of the atoms. Since we desired to maintain consistency in volume, energy, and the number of particles, the constant-energy ensemble (NVE), also known as microcanonical ensemble is applied in the simulations. Both the Si-Si and C-C interactions are computed using the Tersoff potential throughout the simulations while the Si-C interactions are computed with the Morse potential. The MDS results are visualized and analyzed using OVITO, a free and commonly use visualizing tool. It is found that these parameters (exerted force on indenter, operating temperature of the silicon substrate, and size of the indenter) have substantial influence on the behavior of the silicon substrate.

Properties of single-layer graphene with supercell doped by one defect only

2017 ◽  
Vol 31 (27) ◽  
pp. 1750196
Author(s):  
Zongguo Wang ◽  
Shaojing Qin ◽  
Chuilin Wang
Keyword(s):  
Electronic Properties ◽  
Density Functional ◽  
Magnetic State ◽  
Single Layer ◽  
Single Layer Graphene ◽  
Monolayer Graphene ◽  
Hybrid Functional ◽  
Functional Theory ◽  
Spin Polarized ◽  
Different Types

Graphene has vast promising applications in nanoelectronics and spintronics because of its unique magnetic and electronic properties. Making use of an ab initio spin-polarized density functional theory, implemented by the method of the Heyd–Scuseria–Ernzerhof 06 (HSE06) hybrid functional, the properties of various defect dopants in a supercell of a semi-metal monolayer graphene were investigated. We found from our calculation that introducing one defect dopant in a supercell would break the spin sublattice symmetry, and will induce a magnetic state at some appropriate doping concentrations. This paper systematically analyzes the magnetic effects of three types of defects on graphene, that is, vacancy, substitutional dopant and adatoms. Different types of defects will induce various new properties in graphene. The energies and electronic properties of these three types of defects were also calculated.

scholarly journals Tight-Binding Investigation of Structural and Vibrational Properties of Graphene-Single Wall Carbon Nanotube Junctions

2020 ◽  
Author(s):  
Juhi Srivastava ◽  
Anshu Gaur
Keyword(s):  
Charge Transfer ◽  
Carbon Nanostructures ◽  
Tight Binding ◽  
Single Layer ◽  
Hybrid Nanostructures ◽  
Structural Deformation ◽  
Single Layer Graphene ◽  
Vibrational Properties ◽  
Carbon Nanotube Junctions ◽  
Hybrid Devices

Hybrid carbon nanostructures based on single walled carbon nanotubes (SWNT) and single layer graphene (SLG) are drawing much attention lately for their applications in a range of efficient hybrid devices. Few recent studies, addressing the interaction behavior at the heterojunction, consider charge transfer between the constituents (SWNT and SLG) to be responsible for changes in the electronic and vibrational properties in their hybrid system. We report the effect of various factors, arising due to the interactions between atoms of SWNT and SLG, on the structural and vibrational roperties of hybrid nanostructures investigated computationally within the framework of tight-binding DFT. These factors such as the van der Waal’s (vdW) forces, structural deformation and the charge transfer, are seen to affect the Raman active phonon frequencies of SWNT and SLG in the hybrid nanostructure. These factors are already known to affect the vibrational properties on SWNT and SLG separately and in this work, we have explored their role and interplay between these factors in hybrid systems. The contribution of different factors to the total shift observed in phonon frequencies are estimated and it is perceived from our findings that not only the charge transfer but the structural deformations and the vdW forces also affect the vibrational properties of components within the hybrid, with structural deformation being the leading factor. With decreasing separation between SWNT and SLG, the charge transfer and the vdW forces, both increase. However, the increase in vdW forces is relatively much higher and likely to be the main cause for larger Raman shifts observed at smaller separations.

scholarly journals Influence of SiO2 or h-BN substrate on the room-temperature electronic transport in chemically derived single layer graphene

RSC Advances ◽  
2019 ◽  
Vol 9 (65) ◽  
pp. 38011-38016 ◽  
Author(s):  
Zhenping Wang ◽  
Qirong Yao ◽  
Yalei Hu ◽  
Chuan Li ◽  
Marleen Hußmann ◽  
...  
Keyword(s):  
Electronic Transport ◽  
Basal Plane ◽  
Room Temperature ◽  
Dirac Point ◽  
Single Layer ◽  
Single Layer Graphene ◽  
Layer Graphene

Defects in graphene cause scattering and basal plane interactions shift the Dirac-point.

Large scale atomistic simulation of single-layer graphene growth on Ni(111) surface: molecular dynamics simulation based on a new generation of carbon–metal potential

Nanoscale ◽  
2016 ◽  
Vol 8 (2) ◽  
pp. 921-929 ◽  
Author(s):  
Ziwei Xu ◽  
Tianying Yan ◽  
Guiwu Liu ◽  
Guanjun Qiao ◽  
Feng Ding
Keyword(s):  
Molecular Dynamics ◽  
Self Assembly ◽  
Large Scale ◽  
Md Simulation ◽  
Single Layer ◽  
Dynamics Simulation ◽  
Single Layer Graphene ◽  
Simulation Based ◽  
Bond Order Potential ◽  
New Generation

A molecular dynamics (MD) simulation of carbon atom self-assembly on a Ni(111) surface based on a well-designed empirical reactive bond order potential and atomistic details.

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