|   | 
Details
   web
Records
Author Bafekry, A.; Akgenc, B.; Ghergherehchi, M.; Peeters, F.M.
Title Strain and electric field tuning of semi-metallic character WCrCO₂ MXenes with dual narrow band gap Type A1 Journal article
Year (down) 2020 Publication Journal Of Physics-Condensed Matter Abbreviated Journal J Phys-Condens Mat
Volume 32 Issue 35 Pages 355504-355508
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Motivated by the recent successful synthesis of double-M carbides, we investigate structural and electronic properties of WCrC and WCrCO2 monolayers and the effects of biaxial and out-of-plane strain and electric field using density functional theory. WCrC and WCrCO2 monolayers are found to be dynamically stable. WCrC is metallic and WCrCO2 display semi-metallic character with narrow band gap, which can be controlled by strain engineering and electric field. WCrCO2 monolayer exhibits a dual band gap which is preserved in the presence of an electric field. The band gap of WCrCO2 monolayer increases under uniaxial strain while it becomes metallic under tensile strain, resulting in an exotic 2D double semi-metallic behavior. Our results demonstrate that WCrCO2 is a new platform for the study of novel physical properties in two-dimensional Dirac materials and which may provide new opportunities to realize high-speed low-dissipation devices.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000539375800001 Publication Date 2020-04-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.7 Times cited 45 Open Access
Notes ; This work was supported by the National Research Foundation of Korea(NRF) Grant funded by the Korea government(MSIT)(NRF-2017R1A2B2011989). In addition, this work was supported by the Flemish Science Foundation (FW0-Vl). ; Approved Most recent IF: 2.7; 2020 IF: 2.649
Call Number UA @ admin @ c:irua:169756 Serial 6616
Permanent link to this record
 

 
Author Bafekry, A.; Shojai, F.; Hoat, D.M.; Shahrokhi, M.; Ghergherehchi, M.; Nguyen, C.
Title The mechanical, electronic, optical and thermoelectric properties of two-dimensional honeycomb-like of XSb (X = Si, Ge, Sn) monolayers: a first-principles calculations Type A1 Journal article
Year (down) 2020 Publication Rsc Advances Abbreviated Journal Rsc Adv
Volume 10 Issue 51 Pages 30398-30405
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Herein, by using first-principles calculations, we demonstrate a two-dimensional (2D) of XSb (X = Si, Ge, and Sn) monolayers that have a honey-like crystal structure. The structural, mechanical, electronic, thermoelectric efficiency, and optical properties of XSb monolayers are studied.Ab initiomolecular dynamic simulations and phonon dispersion calculations suggests their good thermal and dynamical stabilities. The mechanical properties of XSb monolayers shows that the monolayers are considerably softer than graphene, and their in-plane stiffness decreases from SiSb to SnSb. Our results shows that the single layers of SiSb, GeSb and SnSb are semiconductor with band gap of 1.48, 0.77 and 0.73 eV, respectively. The optical analysis illustrate that the first absorption peaks of the SiSb, GeSb and SnSb monolayers along the in-plane polarization are located in visible range of light which may serve as a promising candidate to design advanced optoelectronic devices. Thermoelectric properties of the XSb monolayers, including Seebeck coefficient, electrical conductivity, electronic thermal conductivity, power factor and figure of merit are calculated as a function of doping level at temperatures of 300 K and 800 K. Between the studied two-dimensional materials (2DM), SiSb single layer may be the most promising candidate for application in the thermoelectric generators.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000561344000009 Publication Date 2020-08-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2046-2069 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.9 Times cited 2 Open Access
Notes ; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF-2017R1A2B2011989). ; Approved Most recent IF: 3.9; 2020 IF: 3.108
Call Number UA @ admin @ c:irua:172074 Serial 6624
Permanent link to this record
 

 
Author Bafekry, A.; Shojaei, F.; Obeid, M.M.; Ghergherehchi, M.; Nguyen, C.; Oskouian, M.
Title Two-dimensional silicon bismotide (SiBi) monolayer with a honeycomb-like lattice: first-principles study of tuning the electronic properties Type A1 Journal article
Year (down) 2020 Publication Rsc Advances Abbreviated Journal Rsc Adv
Volume 10 Issue 53 Pages 31894-31900
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using density functional theory, we investigate a novel two-dimensional silicon bismotide (SiBi) that has a layered GaSe-like crystal structure.Ab initiomolecular dynamic simulations and phonon dispersion calculations suggest its good thermal and dynamical stability. The SiBi monolayer is a semiconductor with a narrow indirect bandgap of 0.4 eV. Our results show that the indirect bandgap decreases as the number of layers increases, and when the number of layers is more than six layers, direct-to-indirect bandgap switching occurs. The SiBi bilayer is found to be very sensitive to an E-field. The bandgap monotonically decreases in response to uniaxial and biaxial compressive strain, and reaches 0.2 eV at 5%, while at 6%, the semiconductor becomes a metal. For both uniaxial and biaxial tensile strains, the material remains a semiconductor and indirect-to-direct bandgap transition occurs at a strain of 3%. Compared to a SiBi monolayer with a layer thickness of 4.89 angstrom, the bandgap decreases with either increasing or decreasing layer thickness, and at a thicknesses of 4.59 to 5.01 angstrom, the semiconductor-to-metal transition happens. In addition, under pressure, the semiconducting character of the SiBi bilayer with a 0.25 eV direct bandgap is preserved. Our results demonstrate that the SiBi nanosheet is a promising candidate for designing high-speed low-dissipation devices.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000565206400027 Publication Date 2020-09-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2046-2069 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.9 Times cited 8 Open Access
Notes ; This work was supported by the National Research Foundation of Korea (NRF) grant, funded by the Korea government (MSIT) (NRF-2017R1A2B2011989). ; Approved Most recent IF: 3.9; 2020 IF: 3.108
Call Number UA @ admin @ c:irua:172045 Serial 6644
Permanent link to this record
 

 
Author Bafekry, A.; Yagmurcukardes, M.; Akgenc, B.; Ghergherehchi, M.; Nguyen, C.
Title Van der Waals heterostructures of MoS₂ and Janus MoSSe monolayers on graphitic boron-carbon-nitride (BC₃, C₃N, C₃N₄ and C₄N₃) nanosheets: a first-principles study Type A1 Journal article
Year (down) 2020 Publication Journal Of Physics D-Applied Physics Abbreviated Journal J Phys D Appl Phys
Volume Issue Pages 1-10
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract In this work, we extensively investigate the structural and electronic properties of van der Waals heterostructures (HTs) constructed by MoS${2}$/$BC3$, MoS${2}$/$C3N$, MoS${2}$/$C3N4$, MoS${2}$/$C4N3$ and those using Janus MoSSe instead of MoS$2$ by performing density functional theory calculations. The electronic band structure calculations and the corresponding partial density of states reveal that the significant changes are driven by quite strong layer-layer interaction between the constitutive layers. Our results show that although all monolayers are semiconductors as free-standing layers, the MoS${2}$/$C3N$ and MoS${2}$/$C4N3$ bilayer HTs display metallic behavior as a consequence of transfer of charge carriers between two constituent layers. In addition, it is found that in MoSSe/$C3N$ bilayer HT, the degree of metallicity is affected by the interface chalcogen atom type when Se atoms are facing to $C3N$ layer, the overlap of the bands around the Fermi level is smaller. Moreover, the half-metallic magnetic $C4N3$ is shown to form magnetic half-metallic trilayer HT with MoS$2$ independent of the stacking sequence, i.e. whether it is sandwiched or two $C4N3$ layer encapsulate MoS$2$ layer. We further analyze the trilayer HTs in which MoS$2$ is encapsulated by two different monolayers and it is revealed that at least with one magnetic monolayer, it is possible to construct a magnetic trilayer. While the trilayer of $C4N3$/MoS${2}$/$BC3$ and $C4N3$/MoS${2}$/$C3N4$ exhibit half-metallic characteristics, $C4N3$/MoS${_2}$/$C3$N possesses a magnetic metallic ground state. Overall, our results reveal that holly structures of BCN crystals are suitable for heterostructure formation even over van der Waals type interaction which significantly changes electronic nature of the constituent layers.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000543344800001 Publication Date 2020-04-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.4 Times cited Open Access
Notes Approved Most recent IF: 3.4; 2020 IF: 2.588
Call Number UA @ admin @ c:irua:169754 Serial 6651
Permanent link to this record
 

 
Author Bafekry, A.; Ghergherehchi, M.; Shayesteh, S.F.; Peeters, F.M.
Title Adsorption of molecules on C3N nanosheet : a first-principles calculations Type A1 Journal article
Year (down) 2019 Publication Chemical physics Abbreviated Journal Chem Phys
Volume 526 Issue 526 Pages 110442
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using first-principles calculations we investigate the interaction of various molecules, including H-2, N-2, CO, CO2, H2O, H2S, NH3, CH4 with a C3N nanosheet. Due to the weaker interaction between H-2, N-2, CO, CO2, H2O, H2S, NH3, and CH4 molecules with C3N, the adsorption energy is small and does not yield any significant distortion of the C3N lattice and the molecules are physisorbed. Calculated charge transfer shows that these molecules act as weak donors. However, adsorption of O-2, NO, NO2 and SO2 molecules are chemisorbed, they receive electrons from C3N and act as a strong acceptor. They interact strongly through hybridizing its frontier orbitals with the p-orbital of C3N, modifying the electronic structure of C3N. Our theoretical studies indicate that C3N-based sensor has a high potential for O-2, NO, NO2 and SO2 molecules detection.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000481606000006 Publication Date 2019-07-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0301-0104 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.767 Times cited 52 Open Access
Notes ; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF-2017R1A2B2011989). In addition, this work was supported by the FLAG-ERA project 2DTRANS and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 1.767
Call Number UA @ admin @ c:irua:161779 Serial 5405
Permanent link to this record
 

 
Author Bafekry, A.; Ghergherehchi, M.; Shayesteh, S.F.
Title Tuning the electronic and magnetic properties of antimonene nanosheets via point defects and external fields: first-principles calculations Type A1 Journal article
Year (down) 2019 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 21 Issue 20 Pages 10552-10566
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Defects are inevitably present in materials, and their existence in a material strongly affects its fundamental physical properties. We have systematically investigated the effects of surface adsorption, substitutional impurities, defect engineering, an electric field and strain engineering on the structural, electronic and magnetic properties of antimonene nanosheets, using spin-polarized density functional calculations based on first-principles. The adsorption or substitution of atoms can locally modify the atomic and electronic structures as well as induce a variety of electronic behaviors including metal, half-metal, ferromagnetic metal, dilute magnetic semiconductor and spin-glass semiconductor. Our calculations show that the presence of typical defects (vacancies and Stone-Wales defect) in antimonene affects the geometrical symmetry as well as the band gap in the electronic band structure and induces magnetism to antimonene. Moreover, by applying an external electric field and strain (uniaxial and biaxial), the electronic structure of antimonene can be easily modified. The calculation results presented in this paper provide a fundamental insight into the tunable nature of the electronic properties of antimonene, supporting its promise for use in future applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000476561000031 Publication Date 2019-04-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9076; 1463-9084 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.123 Times cited 17 Open Access
Notes ; ; Approved Most recent IF: 4.123
Call Number UA @ admin @ c:irua:161945 Serial 5430
Permanent link to this record
 

 
Author Bafekry, A.; Shayesteh, S.F.; Ghergherehchi, M.; Peeters, F.M.
Title Tuning the bandgap and introducing magnetism into monolayer BC3 by strain/defect engineering and adatom/molecule adsorption Type A1 Journal article
Year (down) 2019 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 126 Issue 14 Pages 144304
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using first-principles calculations, we study the structural, electronic, and optical properties of pristine BC3. Our results show that BC3 is a semiconductor which can be useful in optoelectronic device applications. Furthermore, we found that the electronic properties of BC3 can be modified by strain and the type of edge states. With increasing thickness, the indirect bandgap decreases from 0.7 eV (monolayer) to 0.27 eV (bulk). Upon uniaxial tensile strain along the armchair and zigzag directions, the bandgap slightly decreases, and with increasing uniaxial strain, the bandgap decreases, and when reaching -8%, a semiconductor-to-metal transition occurs. By contrast, under biaxial strain, the bandgap increases to 1.2 eV in +8% and decreases to zero in -8%. BC3 nanoribbons with different widths exhibit magnetism at the zigzag edges, while, at the armchair edges, they become semiconductor, and the bandgap is in the range of 1.0-1.2 eV. Moreover, we systematically investigated the effects of adatoms/molecule adsorption and defects on the structural, electronic, and magnetic properties of BC3. The adsorption of various adatoms and molecules as well as topological defects (vacancies and Stone-Wales defects) can modify the electronic properties. Using these methods, one can tune BC3 into a metal, half-metal, ferromagnetic-metal, and dilute-magnetic semiconductor or preserve its semiconducting character. Published under license by AIP Publishing.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000503995300019 Publication Date 2019-10-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.068 Times cited 56 Open Access
Notes Approved Most recent IF: 2.068
Call Number UA @ admin @ c:irua:165160 Serial 6328
Permanent link to this record