AB initio investigation of the nanotribological properties of the h-BN/h-BN and the h-BN/Au(111) interfaces

Download
2019
Baksi, Merve
As the size of the systems reduces due to the advances in fabrication techniques, materials properties that apply at macroscopic scale start to lose their validity. As a reflection of this, friction at the atomic scale does not obey the macroscopic Da Vinci-Amontons’ description. Each interface that experiences losses due to friction therefore requires a separate examination. A particularly intensely studied class of materials from a nanotribological point of view is the two-dimensional networks. In addition to the interface of two-dimensional materials with themselves, the interface between these materials and bulk surfaces are of interest. In this thesis, we examined the nanotribological properties of the h-BN/h-BN (hexagonal boron nitride), and h- BN/Au(111) surfaces using Density Functional Theory (DFT). h-BN/Au(111) interface is particularly relevant for modelling atomic force microscopy (AFM) and friction force microscopy (FFM) experiments since it is expected to reveal superlubric behaviour. We identify and discuss trends in the behavior of the friction force as a function of vertical load for experimentally feasible contact area. Moreover, in order to understand the edge effects of the interface, the interaction between small Au clusters and the h-BN network is also investigated.

Suggestions

AB initio investigation of the nanotribological properties of MoS2/Au(111) interface
Doğan Dağlum, Ümi; Toffoli, Hande; Department of Physics (2020)
Microscopic system is not obey classic friction concept due to atomic interaction and quantum effect in nano scale such as van der Waals forces etc. Therefore, each system display different friction behavior so they should studied one by one. Nanotribology which is sub-field of tribology studies friction at the two dimensional structure such as graphene, silicen and TMD's material using Density Functional Theory. Moreover, atomic force microscopy (AFM) and friction force microscopy (FFM) are used reveal fri...
Density functional theory investigation on thickness and load dependency of friction force between graphene and au interfaces
Şentürk, Duygu Gizem; Toffoli, Hande; Department of Physics (2018)
As the investigation of materials at nano scale become possible with today's technology it is observed that some physical phenomenons have different characteristics at atomistic scale than macroscopic one because of the quantum mechanical effects. One of these physical processes that differs at nano scale is the friction force. While it is expected that the friction force to be independent of contact area and velocity according to Amontos-Coulomb laws, it was observed that it changes by the effect of some p...
Molecular-dynamics simulation of radiation damage on copper clusters
Erkoç, Şakir (2000-07-01)
The effect of radiation damage on copper clusters has been investigated by performing molecular-dynamics simulation using empirical potential energy function for interaction between copper atoms. The external radiation is modeled by giving extra kinetic energy in the range of 5- 50 eV to initially chosen atom in the cluster. It has been found that the atom having extra kinetic energy dissociates independently from the amount of given energy in the studied range.
Ab initio study of the one-monolayer Sb/Si(001) interface
Cakmak, M; Shaltaf, R; Srivastava, GP; Ellialtıoğlu, Süleyman Şinasi (Elsevier BV, 2003-06-10)
Ab initio calculations, based on norm-conserving pseudopotentials and density functional theory, have been performed to investigate the displacive Sb adsorption on the Si(0 0 1) surface with the (2 x 1) reconstruction. For the one-monolayer coverage of Sb, even though the formation of a pure Sb-Sb dimer is energetically more favorable than the interdiffusion of Sb into any of the second and third substrate layers, we found further that this interdiffusion will relieve the tensile stress along the dimer bond...
Metamaterial Absorber Based Multifunctional Sensors
Sabah, Cumali (The Electrochemical Society, 2016-01-01)
In this paper, several important applications of a metamaterial absorber (MA) based sensors such as temperature, pressure, moisture, and density are presented. Since the sensing ability mostly considers the resonance frequency, the frequency range where the resonance shifts occur linearly or non-linearly depending on the temperature, pressure, moisture, and density changes is selected carefully. The model is composed of X shaped resonators (XSR), dielectric substrate, the sensing layer, dielectric substrate...
Citation Formats
M. Baksi, “AB initio investigation of the nanotribological properties of the h-BN/h-BN and the h-BN/Au(111) interfaces,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Physics., Middle East Technical University, 2019.