toggle visibility
Search within Results:
Display Options:

Select All    Deselect All
 |   | 
Details
   print
  Records Links
Author Bafekry, A.; Shahrokhi, M.; Shafique, A.; Jappor, H.R.; Fadlallah, M.M.; Stampfl, C.; Ghergherehchi, M.; Mushtaq, M.; Feghhi, S.A.H.; Gogova, D. url  doi
openurl 
  Title Semiconducting chalcogenide alloys based on the (Ge, Sn, Pb) (S, Se, Te) formula with outstanding properties : a first-principles calculation study Type A1 Journal article
  Year 2021 Publication ACS Omega Abbreviated Journal  
  Volume 6 Issue 14 Pages 9433-9441  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Very recently, a new class of the multicationic and -anionic entropy-stabilized chalcogenide alloys based on the (Ge, Sn, Pb) (S, Se, Te) formula has been successfully fabricated and characterized experimentally [Zihao Deng et al., Chem. Mater. 32, 6070 (2020)]. Motivated by the recent experiment, herein, we perform density functional theory-based first-principles calculations in order to investigate the structural, mechanical, electronic, optical, and thermoelectric properties. The calculations of the cohesive energy and elasticity parameters indicate that the alloy is stable. Also, the mechanical study shows that the alloy has a brittle nature. The GeSnPbSSeTe alloy is a semiconductor with a direct band gap of 0.4 eV (0.3 eV using spin-orbit coupling effect). The optical analysis illustrates that the first peak of Im(epsilon) for the GeSnPbSSeTe alloy along all polarization directions is located in the visible range of the spectrum which renders it a promising material for applications in optical and electronic devices. Interestingly, we find an optically anisotropic character of this system which is highly desirable for the design of polarization-sensitive photodetectors. We have accurately predicted the thermoelectric coefficients and have calculated a large power factor value of 3.7 x 10(11) W m(-1) K-2 s(-1) for p-type. The high p-type power factor is originated from the multiple valleys near the valence band maxima. The anisotropic results of the optical and transport properties are related to the specific tetragonal alloy unit cell.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000640649500012 Publication Date 2021-03-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2470-1343 ISBN (up) Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:178395 Serial 7017  
Permanent link to this record
 

 
Author Bafekry, A.; Shahrokhi, M.; Yagmurcukardes, M.; Gogova, D.; Ghergherehchi, M.; Akgenc, B.; Feghhi, S.A.H. pdf  url
doi  openurl
  Title Surface functionalization of the honeycomb structure of zinc antimonide (ZnSb) monolayer : a first-principles study Type A1 Journal article
  Year 2021 Publication Surface Science Abbreviated Journal Surf Sci  
  Volume 707 Issue Pages 121796  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Structural, electronic, optic and vibrational properties of Zinc antimonide (ZnSb) monolayers and their func-tionalized (semi-fluorinated and fully chlorinated) structures are investigated by means of the first-principles calculations. The phonon dispersion curves reveal the presence of imaginary frequencies and thus confirm the dynamical instability of ZnSb monolayer. The calculated electronic band structure corroborates the metallic character with fully-relativistic calculations. Moreover, we analyze the surface functionalization effect on the structural, vibrational, and electronic properties of the pristine ZnSb monolayer. The semi-fluorinated and fully-chlorinated ZnSb monolayers are shown to be dynamically stable in contrast to the ZnSb monolayer. At the same time, semi-fluorination and fully-chlorination of ZnSb monolayer could effectively modulate the metallic elec-tronic properties of pristine ZnSb. In addition, a magnetic metal to a nonmagnetic semiconductor transition with a band gap of 1 eV is achieved via fluorination, whereas a transition to a semiconducting state with 1.4 eV band gap is found via chlorination of the ZnSb monolayer. According to the optical properties analysis, the first ab-sorption peaks of the fluorinated-and chlorinated-ZnSb monolayers along the in-plane polarization are placed in the infrared range of spectrum, while they are in the middle ultraviolet for the out-of-plane polarization. Interestingly, the optically anisotropic behavior of these novel monolayers along the in-plane polarizations is highly desirable for design of polarization-sensitive photodetectors. The results of the calculations clearly proved that the tunable electronic properties of the ZnSb monolayer can be realized by chemical functionalization for application in the next generation nanoelectronic devices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000626633500001 Publication Date 2020-12-31  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0039-6028 ISBN (up) Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.062 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 2.062  
  Call Number UA @ admin @ c:irua:177623 Serial 7026  
Permanent link to this record
 

 
Author Faraji, M.; Bafekry, A.; Fadlallah, M.M.; Molaei, F.; Hieu, N.N.; Qian, P.; Ghergherehchi, M.; Gogova, D. url  doi
openurl 
  Title Surface modification of titanium carbide MXene monolayers (Ti₂C and Ti₃C₂) via chalcogenide and halogenide atoms Type A1 Journal article
  Year 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 23 Issue 28 Pages 15319-15328  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Inspired by the recent successful growth of Ti2C and Ti3C2 monolayers, here, we investigate the structural, electronic, and mechanical properties of functionalized Ti2C and Ti3C2 monolayers by means of density functional theory calculations. The results reveal that monolayers of Ti2C and Ti3C2 are dynamically stable metals. Phonon band dispersion calculations demonstrate that two-surface functionalization of Ti2C and Ti(3)C(2)via chalcogenides (S, Se, and Te), halides (F, Cl, Br, and I), and oxygen atoms results in dynamically stable novel functionalized monolayer materials. Electronic band dispersions and density of states calculations reveal that all functionalized monolayer structures preserve the metallic nature of both Ti2C and Ti3C2 except Ti2C-O-2, which possesses the behavior of an indirect semiconductor via full-surface oxygen passivation. In addition, it is shown that although halide passivated Ti3C2 structures are still metallic, there exist multiple Dirac-like cones around the Fermi energy level, which indicates that semi-metallic behavior can be obtained upon external effects by tuning the energy of the Dirac cones. In addition, the computed linear-elastic parameters prove that functionalization is a powerful tool in tuning the mechanical properties of stiff monolayers of bare Ti2C and Ti3C2. Our study discloses that the electronic and structural properties of Ti2C and Ti3C2 MXene monolayers are suitable for surface modification, which is highly desirable for material property engineering and device integration.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000672406800001 Publication Date 2021-06-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1463-9076; 1463-9084 ISBN (up) Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.123 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 4.123  
  Call Number UA @ admin @ c:irua:179809 Serial 7027  
Permanent link to this record
 

 
Author Bafekry, A.; Faraji, M.; Fadlallah, M.M.; Khatibani, A.B.; Ziabari, A. abdolahzadeh; Ghergherehchi, M.; Nedaei, S.; Shayesteh, S.F.; Gogova, D. pdf  url
doi  openurl
  Title Tunable electronic and magnetic properties of MoSi₂N₄ monolayer via vacancy defects, atomic adsorption and atomic doping Type A1 Journal article
  Year 2021 Publication Applied Surface Science Abbreviated Journal Appl Surf Sci  
  Volume 559 Issue Pages 149862  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The two dimensional MoSi2N4 (MSN) monolayer exhibiting rich physical and chemical properties was synthesized for the first time last year. We have used the spin-polarized density functional theory to study the effect of different types of point defects on the structural, electronic, and magnetic properties of the MSN monolayer. Adsorbed, substitutionally doped (at different lattice sites), and some kind of vacancies have been considered as point defects. The computational results show all defects studied decrease the MSN monolayer band gap. We found out the H-, O-, and P-doped MSN are n-type conductors. The arsenic-doped MSN, and MSN with vacancy defects have a magnetic moment. The MSN with a Si vacancy defect is a half-metallic which is favorable for spintronic applications, while the MSN with a single N vacancy or double vacancy (N + S) defects are metallic, i. e., beneficial as spin filters and chemical sensors.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000655645300001 Publication Date 2021-05-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0169-4332 ISBN (up) Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.387 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 3.387  
  Call Number UA @ admin @ c:irua:179098 Serial 7038  
Permanent link to this record
 

 
Author Naseri, M.; Bafekry, A.; Faraji, M.; Hoat, D.M.; Fadlallah, M.M.; Ghergherehchi, M.; Sabbaghi, N.; Gogova, D. doi  openurl
  Title Two-dimensional buckled tetragonal cadmium chalcogenides including CdS, CdSe, and CdTe monolayers as photo-catalysts for water splitting Type A1 Journal article
  Year 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 23 Issue 21 Pages 12226-12232  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Pure hydrogen production via water splitting is an ideal strategy for producing clean and sustainable energy. Two-dimensional (2D) cadmium chalcogenide single-layers with a tetragonal crystal structure, namely Tetra-CdX (X = S, Se, and Te) monolayers, are theoretically predicted by means of density functional theory (DFT). Their structural stability and electronic and optical properties are investigated. We find that Tetra-CdX single-layers are thermodynamically stable. Their stability decreases as we go down the 6A group in the periodic table, i.e., from X = S to Se, and Te which also means that the electronegativity decreases. All considered novel monolayers are indirect band gap semiconductors. Using the HSE06 functional the electronic band gaps of CdS, CdSe, and CdTe monolayers are predicted to be 3.10 eV, 2.97 eV, and 2.90 eV, respectively. The impact of mechanical strain on the physical properties was studied, which indicates that compressive strain increases the band gap and tensile strain decreases the band gap. The optical properties of the Tetra-CdX monolayers show the ability of these monolayers to absorb visible light. Due to the suitable band gaps and band edge positions of Tetra-CdX, these newly discovered 2D materials are promising for photocatalytic water splitting.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000651904600001 Publication Date 2021-04-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1463-9076; 1463-9084 ISBN (up) Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.123 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 4.123  
  Call Number UA @ admin @ c:irua:178378 Serial 7041  
Permanent link to this record
 

 
Author Bafekry, A.; Karbasizadeh, S.; Stampfl, C.; Faraji, M.; Hoat, D.M.; Sarsari, I.A.; Feghhi, S.A.H.; Ghergherehchi, M. url  doi
openurl 
  Title Two-dimensional Janus semiconductor BiTeCl and BiTeBr monolayers : a first-principles study on their tunable electronic properties via an electric field and mechanical strain Type A1 Journal article
  Year 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 23 Issue 28 Pages 15216-15223  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Motivated by the recent successful synthesis of highly crystalline ultrathin BiTeCl and BiTeBr layered sheets [Debarati Hajra et al., ACS Nano, 2020, 14, 15626], herein for the first time, we carry out a comprehensive study on the structural and electronic properties of BiTeCl and BiTeBr Janus monolayers using density functional theory (DFT) calculations. Different structural and electronic parameters including the lattice constant, bond lengths, layer thickness in the z-direction, different interatomic angles, work function, charge density difference, cohesive energy and Rashba coefficients are determined to acquire a deep understanding of these monolayers. The calculations show good stability of the studied single layers. BiTeCl and BiTeBr monolayers are semiconductors with electronic bandgaps of 0.83 and 0.80 eV, respectively. The results also show that the semiconductor-metal transformation can be induced by increasing the number of layers. In addition, the engineering of the electronic structure is also studied by applying an electric field, and mechanical uniaxial and biaxial strain. The results show a significant change of the bandgaps and that an indirect-direct band-gap transition can be induced. This study highlights the positive prospect for the application of BiTeCl and BiTeBr layered sheets in novel electronic and energy conversion systems.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000670553900001 Publication Date 2021-06-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1463-9076; 1463-9084 ISBN (up) Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.123 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 4.123  
  Call Number UA @ admin @ c:irua:179827 Serial 7042  
Permanent link to this record
 

 
Author Bafekry, A.; Stampfl, C.; Ghergherehchi, M. pdf  url
doi  isbn
openurl 
  Title Strain, electric-field and functionalization induced widely tunable electronic properties in MoS2/BC3, /C3N and / C3N4 van der Waals heterostructures Type A1 Journal article
  Year 2020 Publication Nanotechnology (Bristol. Print) Abbreviated Journal  
  Volume Issue Pages 295202 pp  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract In this paper, the effect of BC3, C3N and C3N4BC(3) and MoS2/C(3)N4 heterostructures are direct semiconductors with band gaps of 0.4 and 1.74 eV, respectively, while MoS2/C3N is a metal. Furthermore, the influence of strain and electric field on the electronic structure of these van der Waals heterostructures is investigated. The MoS2/BC3 heterostructure, for strains larger than -4%, transforms it into a metal where the metallic character is maintained for strains larger than -6%. The band gap decreases with increasing strain to 0.35 eV (at +2%), while for strain (>+6%) a direct-indirect band gap transition is predicted to occur. For the MoS2/C3N heterostructure, the metallic character persists for all strains considered. On applying an electric field, the electronic properties of MoS2/C3N4 are modified and its band gap decreases as the electric field increases. Interestingly, the band gap reaches 30 meV at +0.8 V/angstrom, and with increase above +0.8 V/angstrom, a semiconductor-to-metal transition occurs. Furthermore, we investigated effects of semi- and full-hydrogenation of MoS2/C3N and we found that it leads to a metallic and semiconducting character, respectively.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000532366000001 Publication Date 2020-04-09  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN (up) 0957-4484 Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 19 Open Access  
  Notes ; This work has supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MSIT)(NRF-2017R1A2B2011989). ; Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:169523 Serial 6444  
Permanent link to this record
Select All    Deselect All
 |   | 
Details
   print

Save Citations:
Export Records: