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Author (up) Bafekry, A.; Nguyen, C., V; Goudarzi, A.; Ghergherehchi, M.; Shafieirad, M. url  doi
openurl 
  Title Investigation of strain and doping on the electronic properties of single layers of C₆N₆ and C₆N₈: a first principles study Type A1 Journal article
  Year 2020 Publication Rsc Advances Abbreviated Journal Rsc Adv  
  Volume 10 Issue 46 Pages 27743-27751  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In this work, by performing first-principles calculations, we explore the effects of various atom impurities on the electronic and magnetic properties of single layers of C(6)N(6)and C6N8. Our results indicate that atom doping may significantly modify the electronic properties. Surprisingly, doping Cr into a holey site of C(6)N(6)monolayer was found to exhibit a narrow band gap of 125 meV upon compression strain, considering the spin-orbit coupling effect. Also, a C atom doped in C(6)N(8)monolayer shows semi-metal nature under compression strains larger than -2%. Our results propose that Mg or Ca doped into strained C(6)N(6)may exhibit small band gaps in the range of 10-30 meV. In addition, a magnetic-to-nonmagnetic phase transition can occur under large tensile strains in the Ca doped C(6)N(8)monolayer. Our results highlight the electronic properties and magnetism of C(6)N(6)and C(6)N(8)monolayers. Our results show that the electronic properties can be effectively modified by atom doping and mechanical strain, thereby offering new possibilities to tailor the electronic and magnetic properties of C(6)N(6)and C(6)N(8)carbon nitride monolayers.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000553911800053 Publication Date 2020-07-24  
  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 11 Open Access  
  Notes ; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (NRF-2017R1A2B2011989). ; Approved Most recent IF: 3.9; 2020 IF: 3.108  
  Call Number UA @ admin @ c:irua:172111 Serial 6553  
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Author (up) Bafekry, A.; Nguyen, C.; Obeid, M.M.; Ghergherehchi, M. url  doi
openurl 
  Title Modulating the electro-optical properties of doped C₃N monolayers and graphene bilayersviamechanical strain and pressure Type A1 Journal article
  Year 2020 Publication New Journal Of Chemistry Abbreviated Journal New J Chem  
  Volume 44 Issue 36 Pages 15785-15792  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In this work, we investigated systematically the electronic and optical properties of B doped C3N monolayers as well as B and N doped graphene bilayers (BN-Gr@2L). We found that the doping of B atoms leads to an enlarged band gap of the C3N monolayer and when the dopant concentration reaches 12.5%, an indirect-to-direct band gap switching occurs. In addition, with co-doping of B and N atoms on the graphene monolayer in the hexagonal configuration, an electronic transition from semi-metal to semiconductor occurs. Our optical results for B-C3N show a broad absorption spectrum in a wide visible range starting from 400 nm to 1000 nm with strong absorption intensity, making it a suitable candidate for nanoelectronic and optoelectronic applications. Interestingly, a transition from semi-metal to semiconductor emerges in the graphene monolayer with doping of B and N atoms. Furthermore, our results demonstrate that the in-plane strain and out-of-plane strain (pressure) can modulate the band gap of the BN-Gr@2L. The controllable electronic properties and optical features of the doped graphene bilayer by strain engineering may facilitate their practical performance for various applications in future.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000571972400054 Publication Date 2020-08-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1144-0546 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.3 Times cited 7 Open Access  
  Notes ; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (NRF-2017R1A2B2011989). ; Approved Most recent IF: 3.3; 2020 IF: 3.269  
  Call Number UA @ admin @ c:irua:171936 Serial 6561  
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Author (up) Bafekry, A.; Obeid, M.; Nguyen, C.; Bagheri Tagani, M.; Ghergherehchi, M. url  doi
openurl 
  Title Graphene hetero-multilayer on layered platinum mineral Jacutingaite (Pt₂HgSe₃): Van der Waals heterostructures with novel optoelectronic and thermoelectric performances Type A1 Journal article
  Year 2020 Publication Journal Of Materials Chemistry A Abbreviated Journal J Mater Chem A  
  Volume 8 Issue 26 Pages 13248-13260  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Motivated by the recent successful synthesis of the layered platinum mineral jacutingaite (Pt2HgSe3), we have studied the optoelectronic, mechanical, and thermoelectric properties of graphene hetero-multilayer on Pt(2)HgSe(3)monolayer (PHS) heterostructures (LG/PHS) by using first-principles calculations. PHS is a topological insulator with a band gap of about 160 meV with fully relativistic calculations; when graphene layers are stacked on PHS, a narrow band gap of similar to 10-15 meV opens. In the presence of gate-voltage and out-of plane strain,i.e.pressure, the electronic properties are modified; the Dirac-cone of graphene can be shifted upwards (downward) to a lower (higher) binding energy. The absorption spectrum shows two peaks, which are located around 216 nm (5.74 eV) and protracted to 490 nm (2.53 eV), indicating that PHS could absorb more visible light. Increasing the number of graphene layers on PHS has a positive impact on the UV-vis light absorption and gives a clear red-shift with enhanced absorption intensity. To investigate the electronic performance of the heterostructure, the electrical conductance and thermopower of a device composed of graphene layers and PHS is examined by a combination of DFT and Green function formalism. The number of graphene layers can significantly tune the thermopower and electrical conductance. This analysis reveals that the heterostructures not only significantly affect the electronic properties, but they can also be used as an efficient way to modulate the optic and thermoelectric properties.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000546391600032 Publication Date 2020-05-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2050-7488; 2050-7496 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 11.9 Times cited 20 Open Access  
  Notes ; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea Government (MSIT) (NRF-2017R1A2B2011989) and Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number 103.01-2019.05. ; Approved Most recent IF: 11.9; 2020 IF: 8.867  
  Call Number UA @ admin @ c:irua:169755 Serial 6529  
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Author (up) Bafekry, A.; Sarsari, I.A.; Faraji, M.; Fadlallah, M.M.; Jappor, H.R.; Karbasizadeh, S.; Nguyen, V.; Ghergherehchi, M. url  doi
openurl 
  Title Electronic and magnetic properties of two-dimensional of FeX (X = S, Se, Te) monolayers crystallize in the orthorhombic structures Type A1 Journal article
  Year 2021 Publication Applied Physics Letters Abbreviated Journal Appl Phys Lett  
  Volume 118 Issue 14 Pages 143102  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In this Letter, we explore the lattice, dynamical stability, and electronic and magnetic properties of FeTe bulk and FeX (X=S, Se, Te) monolayers using the density functional calculations. The phonon dispersion relation, elastic stability criteria, and cohesive energy results show the stability of studied FeX monolayers. The mechanical properties reveal that all FeX monolayers have a brittle nature. Furthermore, these structures are stable as we move down the 6A group in the periodic table, i.e., from S, Se, and Te. The stability and work function decrease as the electronegativity decreases. The spin-polarized electronic structures demonstrate that the FeTe monolayer has a total magnetization of 3.8 mu (B), which is smaller than the magnetization of FeTe bulk (4.7 mu (B)). However, FeSe and FeS are nonmagnetic monolayers. The FeTe monolayer can be a good candidate material for spin filter applications due to its electronic and magnetic properties. This study highlights the bright prospect for the application of FeX monolayers in electronic structures.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000637703700001 Publication Date 2021-04-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-6951; 1077-3118 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 3.411  
  Call Number UA @ admin @ c:irua:177731 Serial 6985  
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Author (up) 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 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  
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Author (up) Bafekry, A.; Shahrokhi, M.; Shafique, A.; Jappor, H.R.; Shojaei, F.; Feghhi, S.A.H.; Ghergherehchi, M.; Gogova, D. pdf  url
doi  openurl
  Title Two-dimensional carbon nitride C₆N nanosheet with egg-comb-like structure and electronic properties of a semimetal Type A1 Journal article
  Year 2021 Publication Nanotechnology Abbreviated Journal Nanotechnology  
  Volume 32 Issue 21 Pages 215702  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract In this study, the structural, electronic and optical properties of theoretically predicted C6N monolayer structure are investigated by means of Density Functional Theory-based First-Principles Calculations. Phonon band dispersion calculations and molecular dynamics simulations reveal the dynamical and thermal stability of the C6N single-layer structure. We found out that the C6N monolayer has large negative in-plane Poisson's ratios along both X and Y direction and the both values are almost four times that of the famous-pentagraphene. The electronic structure shows that C6N monolayer is a semi-metal and has a Dirac-point in the BZ. The optical analysis using the random phase approximation method constructed over HSE06 illustrates that the first peak of absorption coefficient of the C6N monolayer along all polarizations is located in the IR range of spectrum, while the second absorption peak occurs in the visible range, which suggests its potential applications in optical and electronic devices. Interestingly, optically anisotropic character of this system is highly desirable for the design of polarization-sensitive photodetectors. Thermoelectric properties such as Seebeck coefficient, electrical conductivity, electronic thermal conductivity and power factor are investigated as a function of carrier doping at temperatures 300, 400, and 500 K. In general, we predict that the C6N monolayer could be a new platform for study of novel physical properties in two-dimensional semi-metal materials, which may provide new opportunities to realize high-speed low-dissipation devices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000624531500001 Publication Date 2020-12-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0957-4484 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.44 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 3.44  
  Call Number UA @ admin @ c:irua:176648 Serial 6740  
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Author (up) 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 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  
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Author (up) Bafekry, A.; Shayesteh, S.F.; Ghergherehchi, M.; Peeters, F.M. pdf  doi
openurl 
  Title Tuning the bandgap and introducing magnetism into monolayer BC3 by strain/defect engineering and adatom/molecule adsorption Type A1 Journal article
  Year 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 48 Open Access  
  Notes Approved Most recent IF: 2.068  
  Call Number UA @ admin @ c:irua:165160 Serial 6328  
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Author (up) Bafekry, A.; Shayesteh, S.F.; Peeters, F.M. url  doi
openurl 
  Title C3N Monolayer: Exploring the Emerging of Novel Electronic and Magnetic Properties with Adatom Adsorption, Functionalizations, Electric Field, Charging, and Strain Type A1 Journal article
  Year 2019 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C  
  Volume 123 Issue 19 Pages 12485-12499  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Two-dimensional polyaniline with structural unit C3N is an indirect semiconductor with 0.4 eV band gap, which has attracted a lot of interest because of its unusual electronic, optoelectronic, thermal, and mechanical properties useful for various applications. Adsorption of adatoms is an effective method to improve and tune the properties of C3N. Using first-principles calculations, we investigated the adsorption of adatoms, including H, O, S, F, Cl, B, C, Si, N, P, Al, Li, Na, K, Be, Mg, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn, on C3N. Depending on the adatom size and the number of valence electrons, they may induce metallic, half-metallic, semiconducting, and ferromagnetic-metallic behavior. In addition, we investigate the effects of an electrical field, charging, and strain on C3N and found how the electronic and magnetic properties are modified. Semi- and full hydrogenation are studied. From the mechanical and thermal stability of C3N monolayer, we found it to be a hard material that can withstand large strain. From our calculations, we gained novel insights into the properties of C3N demonstrating its unique electronic and magnetic properties that can be useful for semiconducting, nanosensor, and catalytic applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000468368800053 Publication Date 2019-04-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-7447; 1932-7455 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.536 Times cited 67 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FW0-V1). The authors thank Keyvan Nazifi from the Cluster Center of Faculty of Science, Guilan University, for his help. They acknowledge OpenMX team for OpenMX code. ; Approved Most recent IF: 4.536  
  Call Number UA @ admin @ c:irua:160323 Serial 5196  
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Author (up) Bafekry, A.; Shayesteh, S.F.; Peeters, F.M. url  doi
openurl 
  Title Introducing novel electronic and magnetic properties in C3N nanosheets by defect engineering and atom substitution Type A1 Journal article
  Year 2019 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 21 Issue 37 Pages 21070-21083  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using first-principles calculations the effect of topological defects, vacancies, Stone-Wales and anti-site and substitution of atoms, on the structure and electronic properties of monolayer C3N are investigated. Vacancy defects introduce localized states near the Fermi level and a local magnetic moment. While pristine C3N is an indirect semiconductor with a 0.4 eV band gap, with substitution of O, S and Si atoms for C, it remains a semiconductor with a band gap in the range 0.25-0.75 eV, while it turns into a metal with H, Cl, B, P, Li, Na, K, Be and Mg substitution. With F substitution, it becomes a dilute-magnetic semiconductor, while with Ca substitution it is a ferromagnetic-metal. When replacing the N host atom, C3N turns into: a metal (H, O, S, C, Si, P, Li and Be), ferromagnetic-metal (Mg), half-metal (Ca) and spin-glass semiconductor (Na and K). Moreover, the effects of charging and strain on the electronic properties of Na atom substitution in C3N are investigated. We found that the magnetic moment decreases or increases depending on the type and size of strain (tensile or compression). Our study shows how the band gap and magnetism in monolayer C3N can be tuned by introducing defects and atom substitution. The so engineered C3N can be a good candidate for future low dimensional devices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000489984200050 Publication Date 2019-09-09  
  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 52 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 4.123  
  Call Number UA @ admin @ c:irua:163732 Serial 5418  
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Author (up) Bafekry, A.; Shayesteh, S.F.; Peeters, F.M. url  doi
openurl 
  Title Two-dimensional carbon nitride (2DCN) nanosheets : tuning of novel electronic and magnetic properties by hydrogenation, atom substitution and defect engineering Type A1 Journal article
  Year 2019 Publication Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 126 Issue 21 Pages 215104  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract By employing first-principles calculations within the framework of density functional theory, we investigated the structural, electronic, and magnetic properties of graphene and various two-dimensional carbon-nitride (2DNC) nanosheets. The different 2DCN gives rise to diverse electronic properties such as metals (C3N2), semimetals (C4N and C9N4), half-metals (C4N3), ferromagnetic-metals (C9N7), semiconductors (C2N, C3N, C3N4, C6N6, and C6N8), spin-glass semiconductors (C10N9 and C14N12), and insulators (C2N2). Furthermore, the effects of adsorption and substitution of hydrogen atoms as well as N-vacancy defects on the electronic and magnetic properties are systematically studied. The introduction of point defects, including N vacancies, interstitial H impurity into graphene and different 2DCN crystals, results in very different band structures. Defect engineering leads to the discovery of potentially exotic properties that make 2DCN interesting for future investigations and emerging technological applications with precisely tailored properties. These properties can be useful for applications in various fields such as catalysis, energy storage, nanoelectronic devices, spintronics, optoelectronics, and nanosensors. Published under license by AIP Publishing.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000504007300023 Publication Date 2019-12-02  
  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 57 Open Access  
  Notes Approved Most recent IF: 2.068  
  Call Number UA @ admin @ c:irua:165733 Serial 6329  
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Author (up) Bafekry, A.; Shojaei, F.; Obeid, M.M.; Ghergherehchi, M.; Nguyen, C.; Oskouian, M. url  doi
openurl 
  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 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  
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Author (up) Bafekry, A.; Shojai, F.; Hoat, D.M.; Shahrokhi, M.; Ghergherehchi, M.; Nguyen, C. url  doi
openurl 
  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 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  
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Author (up) Bafekry, A.; Stampfl, C.; Akgenc, B.; Ghergherehchi, M. url  doi
openurl 
  Title Control of C3N4 and C4N3 carbon nitride nanosheets' electronic and magnetic properties through embedded atoms Type A1 Journal article
  Year 2020 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 22 Issue 4 Pages 2249-2261  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In the present work, the effect of various embedded atom impurities on tuning electronic and magnetic properties of C3N4 and C4N3 nanosheets have been studied using first-principles calculations. Our calculations show that C3N4 is a semiconductor and it exhibits extraordinary electronic properties such as dilute-magnetic semiconductor (with H, F, Cl, Be, V, Fe and Co); metal (with N, P, Mg and Ca), half-metal (with Li, Na, K, Al, Sc, Cr, Mn, and Cu) and semiconductor (with O, S, B, C, Si, Ti, Ni and Zn) with the band gaps in the range of 0.3-2.0 eV depending on the species of embedded atom. The calculated electronic properties reveal that C4N3 is a half-metal and it retains half-metallic character with embedded H, O, S, F, B, N, P, Be, Mg, Al, Sc, V, Fe, Ni and Zn atoms. The substitution of Cl, C, Cr and Mn atoms create ferromagnetic-metal character in the C4N3 nanosheet, embedded Co and Cu atoms exhibit a dilute-magnetic semiconductor nature, and embedded Ti atoms result in the system becoming a semiconductor. Therefore, our results reveal the fact that the band gap and magnetism can be modified or induced by various atom impurities, thus, offering effective possibilities to tune the electronic and magnetic properties of C3N4 and C4N3 nanosheets.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000510729400042 Publication Date 2019-12-24  
  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 3.3 Times cited 18 Open Access  
  Notes ; This work has supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF-2017R1A2B2011989). B. Akgenc acknowledges financial support the Kirklareli University-BAP under the Project No 189 and TUBITAK ULAKBIM, High Performance and Grid Computing Center. ; Approved Most recent IF: 3.3; 2020 IF: 4.123  
  Call Number UA @ admin @ c:irua:166553 Serial 6476  
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Author (up) Bafekry, A.; Stampfl, C.; Akgenc, B.; Mortazavi, B.; Ghergherehchi, M.; Nguyen, C.V. url  doi
openurl 
  Title Embedding of atoms into the nanopore sites of the C₆N₆ and C₆N₈ porous carbon nitride monolayers with tunable electronic properties Type A1 Journal article
  Year 2020 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 22 Issue 11 Pages 6418-6433  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using first-principles calculations, we study the effect of embedding various atoms into the nanopore sites of both C6N6 and C6N8 monolayers. Our results indicate that the embedded atoms significantly affect the electronic and magnetic properties of C6N6 and C6N8 monolayers and lead to extraordinary and multifarious electronic properties, such as metallic, half-metallic, spin-glass semiconductor and dilute-magnetic semiconductor behaviour. Our results reveal that the H atom concentration dramatically affects the C6N6 monolayer. On increasing the H coverage, the impurity states also increase due to H atoms around the Fermi-level. C6N6 shows metallic character when the H atom concentration reaches 6.25%. Moreover, the effect of charge on the electronic properties of both Cr@C6N6 and C@C6N8 is also studied. Cr@C6N6 is a ferromagnetic metal with a magnetic moment of 2.40 mu(B), and when 0.2 electrons are added and removed, it remains a ferromagnetic metal with a magnetic moment of 2.57 and 2.77 mu(B), respectively. Interestingly, one can observe a semi-metal, in which the VBM and CBM in both spin channels touch each other near the Fermi-level. C@C6N8 is a semiconductor with a nontrivial band gap. When 0.2 electrons are removed, it remains metallic, and under excess electronic charge, it exhibits half-metallic behaviour.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000523409400037 Publication Date 2020-02-20  
  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 3.3 Times cited 17 Open Access  
  Notes ; This work was supported by a National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (NRF-2017R1A2B2011989). ; Approved Most recent IF: 3.3; 2020 IF: 4.123  
  Call Number UA @ admin @ c:irua:168617 Serial 6504  
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Author (up) Bafekry, A.; Stampfl, C.; Faraji, M.; Yagmurcukardes, M.; Fadlallah, M.M.; Jappor, H.R.; Ghergherehchi, M.; Feghhi, S.A.H. doi  openurl
  Title A Dirac-semimetal two-dimensional BeN4 : thickness-dependent electronic and optical properties Type A1 Journal article
  Year 2021 Publication Applied Physics Letters Abbreviated Journal Appl Phys Lett  
  Volume 118 Issue 20 Pages 203103  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Motivated by the recent experimental realization of a two-dimensional (2D) BeN4 monolayer, in this study we investigate the structural, dynamical, electronic, and optical properties of a monolayer and few-layer BeN4 using first-principles calculations. The calculated phonon band dispersion reveals the dynamical stability of a free-standing BeN4 layer, while the cohesive energy indicates the energetic feasibility of the material. Electronic band dispersions show that monolayer BeN4 is a semi-metal whose conduction and valence bands touch each other at the Sigma point. Our results reveal that increasing the layer number from single to six-layers tunes the electronic nature of BeN4. While monolayer and bilayer structures display a semi-metallic behavior, structures thicker than that of three-layers exhibit a metallic nature. Moreover, the optical parameters calculated for monolayer and bilayer structures reveal that the bilayer can absorb visible light in the ultraviolet and visible regions better than the monolayer structure. Our study investigates the electronic properties of Dirac-semimetal BeN4 that can be an important candidate for applications in nanoelectronic and optoelectronic. Published under an exclusive license by AIP Publishing.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000691329900002 Publication Date 2021-05-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-6951; 1077-3118 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 3.411  
  Call Number UA @ admin @ c:irua:181725 Serial 6980  
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Author (up) 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 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  
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Author (up) Bafekry, A.; Stampfl, C.; Ghergherehchi, M.; Shayesteh, S.F. pdf  url
doi  openurl
  Title A first-principles study of the effects of atom impurities, defects, strain, electric field and layer thickness on the electronic and magnetic properties of the C2N nanosheet Type A1 Journal article
  Year 2020 Publication Carbon Abbreviated Journal Carbon  
  Volume 157 Issue 157 Pages 371-384  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using the first-principles calculations, we explore the structural and novel electronic/optical properties of the C2N nanosheet. To this goal, we systematically investigate the affect of layer thickness, electrical field and strain on the electronic properties of the C2N nanosheet. By increasing the thickness of C2N, we observed that the band gap decreases. Moreover, by applying an electrical field to bilayer C2N, the band gap decreases and a semiconductor-to-metal transition can occur. Our results also confirm that uniaxial and biaxial strain can effectively alter the band gap of C2N monolayer. Furthermore, we show that the electronic and magnetic properties of C2N can be modified by the adsorption and substitution of various atoms. Depending on the species of embedded atoms, they may induce semiconductor (O, C, Si and Be), metal (S, N, P, Na, K, Mg and Ca), dilute-magnetic semiconductor (H, F, B), or ferro-magnetic-metal (Cl, Li) character in C2N monolayer. It was also found that the inclusion of hydrogen or oxygen impurities and nitrogen vacancies, can induce magnetism in the C2N monolayer. These extensive calculations can be useful to guide future studies to modify the electronic/optical properties of two-dimensional materials. (C) 2019 Elsevier Ltd. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000502548500044 Publication Date 2019-10-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0008-6223 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 10.9 Times cited 49 Open Access  
  Notes ; This work was supported by the National Research Foundation of Korea grant funded by the Korea government (MSIT) (NRF-2017R1A2B2011989). We are thankful for comments by Meysam Baghery Tagani from department of physics in University of Guilan and Bohayra Mortazavi from Gottfried Wilhelm Leibniz Universitat Hannover, Hannover, Germany. ; Approved Most recent IF: 10.9; 2020 IF: 6.337  
  Call Number UA @ admin @ c:irua:165024 Serial 6283  
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Author (up) Bafekry, A.; Stampfl, C.; Naseri, M.; Fadlallah, M.M.; Faraji, M.; Ghergherehchi, M.; Gogova, D.; Feghhi, S.A.H. url  doi
openurl 
  Title Effect of electric field and vertical strain on the electro-optical properties of the MoSi2N4 bilayer : a first-principles calculation Type A1 Journal article
  Year 2021 Publication Journal Of Applied Physics Abbreviated Journal J Appl Phys  
  Volume 129 Issue 15 Pages 155103  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Recently, a two-dimensional (2D) MoSi 2N 4 (MSN) structure has been successfully synthesized [Hong et al., Science 369(6504), 670-674 (2020)]. Motivated by this result, we investigate the structural, electronic, and optical properties of MSN monolayer (MSN-1L) and bilayer (MSN-2L) under the applied electric field (E-field) and strain using density functional theory calculations. We find that the MSN-2L is a semiconductor with an indirect bandgap of 1.60 (1.80)eV using Perdew-Burke-Ernzerhof (HSE06). The bandgap of MSN-2L decreases as the E-field increases from 0.1 to 0.6V/angstrom and for larger E-field up to 1.0V/angstrom the bilayer becomes metallic. As the vertical strain increases, the bandgap decreases; more interestingly, a semiconductor to a metal phase transition is observed at a strain of 12 %. Furthermore, the optical response of the MSN-2L is in the ultraviolet (UV) region of the electromagnetic spectrum. The absorption edge exhibits a blue shift by applying an E-field or a vertical compressive strain. The obtained interesting properties suggest MSN-2L as a promising material in electro-mechanical and UV opto-mechanical devices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000640620400003 Publication Date 2021-04-15  
  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 Open Access OpenAccess  
  Notes Approved Most recent IF: 2.068  
  Call Number UA @ admin @ c:irua:178233 Serial 6981  
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Author (up) Bafekry, A.; Stampfl, C.; Peeters, F.M. url  doi
openurl 
  Title Dirac half-metallicity of thin PdCl₃ nanosheets : investigation of the effects of external fields, surface adsorption and defect engineering on the electronic and magnetic properties Type A1 Journal article
  Year 2020 Publication Scientific Reports Abbreviated Journal Sci Rep-Uk  
  Volume 10 Issue 1 Pages 213-215  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract PdCl3 belongs to a novel class of Dirac materials with Dirac spin-gapless semiconducting characteristics. In this paper based, on first-principles calculations, we have systematically investigated the effect of adatom adsorption, vacancy defects, electric field, strain, edge states and layer thickness on the electronic and magnetic properties of PdCl3 (palladium trichloride). Our results show that when spin-orbital coupling is included, PdCl3 exhibits the quantum anomalous Hall effect with a non-trivial band gap of 24 meV. With increasing number of layers, from monolayer to bulk, a transition occurs from a Dirac half-metal to a ferromagnetic metal. On application of a perpendicular electrical field to bilayer PdCl3, we find that the energy band gap decreases with increasing field. Uniaxial and biaxial strain, significantly modifies the electronic structure depending on the strain type and magnitude. Adsorption of adatom and topological defects have a dramatic effect on the electronic and magnetic properties of PdCl3. In particular, the structure can become a metal (Na), half-metal (Be, Ca, Al, Ti, V, Cr, Fe and Cu with, respective, 0.72, 9.71, 7.14, 6.90, 9.71, 4.33 and 9.5 μB magnetic moments), ferromagnetic-metal (Sc, Mn and Co with 4.55, 7.93 and 2.0 μB), spin-glass semiconductor (Mg, Ni with 3.30 and 8.63 μB), and dilute-magnetic semiconductor (Li, K and Zn with 9.0, 9.0 and 5.80 μB magnetic moment, respectively). Single Pd and double Pd + Cl vacancies in PdCl3 display dilute-magnetic semiconductor characteristics, while with a single Cl vacancy, the material becomes a half-metal. The calculated optical properties of PdCl3 suggest it could be a good candidate for microelectronic and optoelectronics devices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000562795700001 Publication Date 2020-01-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2045-2322 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.6 Times cited 26 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl). We are thankful for comments by Sevil Sarikurt from the department of physics in Dokuz Eylul University. In addition, we acknowledge OpenMX team for OpenMX code. ; Approved Most recent IF: 4.6; 2020 IF: 4.259  
  Call Number UA @ admin @ c:irua:169751 Serial 6483  
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Author (up) Bafekry, A.; Stampfl, C.; Peeters, F.M. pdf  doi
openurl 
  Title The electronic, optical, and thermoelectric properties of monolayer PbTe and the tunability of the electronic structure by external fields and defects Type A1 Journal article
  Year 2020 Publication Physica Status Solidi B-Basic Solid State Physics Abbreviated Journal Phys Status Solidi B  
  Volume Issue Pages 2000182-12  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract First‐principles calculations, within the framework of density functional theory, are used to investigate the structural, electronic, optical, and thermoelectric properties of monolayer PbTe. The effect of layer thickness, electric field, strain, and vacancy defects on the electronic and magnetic properties is systematically studied. The results show that the bandgap decreases as the layer thickness increases from monolayer to bulk. With application of an electric field on bilayer PbTe, the bandgap decreases from 70 meV (0.2 V Å⁻¹) to 50 meV (1 V Å⁻¹) when including spin–orbit coupling (SOC). Application of uniaxial strain induces a direct‐to‐indirect bandgap transition for strain greater than +6%. In addition, the bandgap decreases under compressive biaxial strain (with SOC). The effect of vacancy defects on the electronic properties of PbTe is also investigated. Such vacancy defects turn PbTe into a ferromagnetic metal (single vacancy Pb) with a magnetic moment of 1.3 μB, and into an indirect semiconductor with bandgap of 1.2 eV (single Te vacancy) and 1.5 eV (double Pb + Te vacancy). In addition, with change of the Te vacancy concentration, a bandgap of 0.38 eV (5.55%), 0.43 eV (8.33%), and 0.46 eV (11.11%) is predicted.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000527679200001 Publication Date 2020-04-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-1972 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.6 Times cited 37 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 TMD and the Flemish Science Foundation (FWO-Vl). The authors are thankful for comments by Mohan Verma from the Computational Nanoionics Research Lab, Department of Applied Physics, Bhilai, India and to Francesco Buonocore from ENEA, Casaccia Research Centre, Rome, Italy. ; Approved Most recent IF: 1.6; 2020 IF: 1.674  
  Call Number UA @ admin @ c:irua:168730 Serial 6502  
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Author (up) Bafekry, A.; Stampfl, C.; Shayesteh, S.F. pdf  url
doi  openurl
  Title A first-principles study of C3N nanostructures : control and engineering of the electronic and magnetic properties of nanosheets, tubes and ribbons Type A1 Journal article
  Year 2020 Publication Chemphyschem Abbreviated Journal Chemphyschem  
  Volume 21 Issue 2 Pages 164-174  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using first-principles calculations we systematically investigate the atomic, electronic and magnetic properties of novel two-dimensional materials (2DM) with a stoichiometry C3N which has recently been synthesized. We investigate how the number of layers affect the electronic properties by considering monolayer, bilayer and trilayer structures, with different stacking of the layers. We find that a transition from semiconducting to metallic character occurs which could offer potential applications in future nanoelectronic devices. We also study the affect of width of C3N nanoribbons, as well as the radius and length of C3N nanotubes, on the atomic, electronic and magnetic properties. Our results show that these properties can be modified depending on these dimensions, and depend markedly on the nature of the edge states. Functionalization of the nanostructures by the adsorption of H adatoms is found induce metallic, half-metallic, semiconducting and ferromagnetic behavior, which offers an approach to tailor the properties, as can the application of strain. Our calculations give insight into this new family of C3N nanostructures, which reveal unusual electronic and magnetic properties, and may have great potential in applications such as sensors, electronics and optoelectronic at the nanoscale.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000503453100001 Publication Date 2019-11-09  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1439-4235 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.9 Times cited 27 Open Access  
  Notes ; ; Approved Most recent IF: 2.9; 2020 IF: 3.075  
  Call Number UA @ admin @ c:irua:165045 Serial 6282  
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Author (up) Bafekry, A.; Stampfl, C.; Shayesteh, S.F.; Peeters, F.M. pdf  doi
openurl 
  Title Exploiting the novel electronic and magnetic structure of C3Nvia functionalization and conformation Type A1 Journal article
  Year 2019 Publication Advanced Electronic Materials Abbreviated Journal Adv Electron Mater  
  Volume 5 Issue 5 Pages 1900459  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract 2D polyaniline, C3N, is of recent high interest due to its unusual properties and potential use in various technological applications. In this work, through systematic first-principles calculations, the atomic, electronic, and magnetic structure of C3N and the changes induced due to functionalization by the adsorption of hydrogen, oxygen, and fluorine, for different coverages and sites, as well as on formation of nanoribbons including the effect of adsorbed hydrogen and oxygen, and the effect of strain, are investigated. Among other interesting phenomena, for hydrogen adsorption, a semiconductor-to-topological insulator transition, where two Dirac-points appear around the Fermi level, as well as ferromagnetic ordering for both hydrogen and oxygen functionalization, is identified. Considering C3N nanoribbons, adsorption of H leads to significant changes in the electronic properties, such as transforming the structures from semiconductor to metallic. Furthermore, investigating the effect of strain on the physical properties, it is found that the band gap can be significantly altered and controlled. The present findings predict that a wide variation in the magnetic and electronic structure of C3N can be achieved by adatom functionalization and conformation indicating its high potential for use in various technological applications, ranging from catalysis, energy storage, and nanoelectronic devices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000486528200001 Publication Date 2019-09-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2199-160x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.193 Times cited 35 Open Access  
  Notes ; This work was supported by the FLAG-ERA project 2DTRANS and the Flemish Science Foundation (FWO-Vl). In addition, we acknowledge the OpenMX team for OpenMX code. ; Approved Most recent IF: 4.193  
  Call Number UA @ admin @ c:irua:162790 Serial 5414  
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Author (up) Bafekry, A.; Van Nguyen, C.; Stampfl, C.; Akgenc, B.; Ghergherehchi, M. pdf  doi
openurl 
  Title Oxygen vacancies in the single layer of Ti₂CO₂ MXene: effects of gating voltage, mechanical strain, and atomic impurities Type A1 Journal article
  Year 2020 Publication Physica Status Solidi B-Basic Solid State Physics Abbreviated Journal Phys Status Solidi B  
  Volume Issue Pages 2000343-2000349  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Herein, using first-principles calculations the structural and electronic properties of the Ti(2)CO(2)MXene monolayer with and without oxygen vacancies are systematically investigated with different defect concentrations and patterns, including partial, linear, local, and hexagonal types. The Ti(2)CO(2)monolayer is found to be a semiconductor with a bandgap of 0.35 eV. The introduction of oxygen vacancies tends to increase the bandgap and leads to electronic phase transitions from nonmagnetic semiconductors to half-metals. Moreover, the semiconducting characteristic of O-vacancy Ti(2)CO(2)can be adjusted via electric fields, strain, and F-atom substitution. In particular, an electric field can be used to alter the nonmagnetic semiconductor of O-vacancy Ti(2)CO(2)into a magnetic one or into a half-metal, whereas the electronic phase transition from a semiconductor to metal can be achieved by applying strain and F-atom substitution. The results provide a useful guide for practical applications of O-vacancy Ti(2)CO(2)monolayers in nanoelectronic and spinstronic nanodevices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000571060800001 Publication Date 2020-09-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-1972 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.6 Times cited Open Access  
  Notes ; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (NRF-2017R1A2B2011989). ; Approved Most recent IF: 1.6; 2020 IF: 1.674  
  Call Number UA @ admin @ c:irua:171948 Serial 6576  
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Author (up) Bafekry, A.; Yagmurcukardes, M.; Akgenc, B.; Ghergherehchi, M.; Mortazavi, B. url  doi
openurl 
  Title First-principles investigation of electronic, mechanical and thermoelectric properties of graphene-like XBi (X = Si, Ge, Sn) monolayers Type A1 Journal article
  Year 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 23 Issue 21 Pages 12471-12478  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Research progress on single layer group III monochalcogenides has been increasing rapidly owing to their interesting physics. Herein, we investigate the dynamically stable single layer forms of XBi (X = Ge, Si or Sn) using density functional theory calculations. Phonon band dispersion calculations and ab initio molecular dynamics simulations reveal the dynamical and thermal stability of the considered monolayers. Raman spectra calculations indicate the existence of 5 Raman active phonon modes, 3 of which are prominent and can be observed in possible Raman measurements. The electronic band structures of the XBi single layers were investigated with and without the effects of spin-orbit coupling (SOC). Our results show that XBi single layers show semiconducting properties with narrow band gap values without SOC. However, only single layer SiBi is an indirect band gap semiconductor, while GeBi and SnBi exhibit metallic behaviors when adding spin-orbit coupling effects. In addition, the calculated linear elastic parameters indicate the soft nature of the predicted monolayers. Moreover, our predictions for the thermoelectric properties of single layer XBi reveal that SiBi is a good thermoelectric material with increasing temperature. Overall, it is proposed that single layer XBi structures can be alternative, stable 2D single layers with varying electronic and thermoelectric properties.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000653851100001 Publication Date 2021-04-08  
  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 Open Access OpenAccess  
  Notes Approved Most recent IF: 4.123  
  Call Number UA @ admin @ c:irua:179007 Serial 6992  
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Author (up) Bafekry, A.; Yagmurcukardes, M.; Akgenc, B.; Ghergherehchi, M.; Nguyen, C. doi  openurl
  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 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  
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Author (up) Bafekry, A.; Yagmurcukardes, M.; Shahrokhi, M.; Ghergherehchi, M. pdf  doi
openurl 
  Title Electro-optical properties of monolayer and bilayer boron-doped C₃N: Tunable electronic structure via strain engineering and electric field Type A1 Journal article
  Year 2020 Publication Carbon Abbreviated Journal Carbon  
  Volume 168 Issue Pages 220-229  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In this work, the structural, electronic and optical properties of monolayer and bilayer of boron doped C3N are investigated by means of density functional theory-based first-principles calculations. Our results show that with increasing the B dopant concentration from 3.1% to 12.5% in the hexagonal pattern, an indirect-to-direct band gap (0.8 eV) transition occurs. Furthermore, we study the effect of electric field and strain on the B doped C3N bilayer (B-C3N@2L). It is shown that by increasing E-field strength from 0.1 to 0.6V/angstrom, the band gap displays almost a linear decreasing trend, while for the > 0.6V/angstrom, we find dual narrow band gap with of 50 meV (in parallel E-field) and 0.4 eV (in antiparallel E-field). Our results reveal that in-plane and out-of-plane strains can modulate the band gap and band edge positions of the B-C3N@2L. Overall, we predict that B-C3N@2L is a new platform for the study of novel physical properties in layered two-dimensional materials (2DM) which may provide new opportunities to realize high-speed low-dissipation devices. (C) 2020 Elsevier Ltd. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000565900900008 Publication Date 2020-07-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0008-6223 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 10.9 Times cited 21 Open Access  
  Notes ; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government(MSIT) (NRF-2017R1A2B2011989). M. Yagmurcukardes acknowledges Flemish Science Foundation (FWO-VI) by a postdoctoral fellowship. ; Approved Most recent IF: 10.9; 2020 IF: 6.337  
  Call Number UA @ admin @ c:irua:171914 Serial 6500  
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Author (up) Bafekry, A.; Yagmurcukardes, M.; Shahrokhi, M.; Ghergherehchi, M.; Kim, D.; Mortazavi, B. pdf  doi
openurl 
  Title Electro-optical and mechanical properties of Zinc antimonide (ZnSb) monolayer and bilayer : a first-principles study Type A1 Journal article
  Year 2021 Publication Applied Surface Science Abbreviated Journal Appl Surf Sci  
  Volume 540 Issue 1 Pages 148289  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Latest synthesis of ZnSb monolayer, encouraged us to conduct density functional theory (DFT) simulations in order to study the structural, magnetic, electronic/optical and mechanical features of the sp2-hybridized honeycomb ZnSb monolayer (ML-ZnSb) and bilayer (BL-ZnSb). Our structural optimizations reveal that ML-ZnSb is an anisotropic hexagonal structure while BL-ZnSb is composed of shifted ZnSb layers which are covalently binded. ML-ZnSb is found to be a ferromagnetic metal, in contrast BL-ZnSb has a non-magnetic indirect band gap semiconducting ground state. For the in-plane polarization, first absorption peak of ML-ZnSb and BL-ZnSb confirm the absorbance of the light within the infrared domain wand visible range, respectively. Moreover, our results reveal that the layer-layer chemical bonding in BL-ZnSb significantly enhances the mechanical response of ML-ZnSb whose in-plane stiness is the smallest among all 2D materials (2DM). Notably, the strong in-plane anisotropy of ML-ZnSb in its stiness reduces in BL-ZnSb.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000599883200005 Publication Date 2020-11-09  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0169-4332 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.387 Times cited 1 Open Access Not_Open_Access  
  Notes ; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF-2017R1A2B2011989). Computational resources were provided by the Flemish Supercomputer Center (VSC). M.Y. is supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship. B.M. and X. Z. appreciate the funding by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germanys Excellence Strategy within the Cluster of Excellence PhoenixD (EXC 2122, Project ID 390833453). ; Approved Most recent IF: 3.387  
  Call Number UA @ admin @ c:irua:174956 Serial 6688  
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Author (up) Bagherpour, A.; Baral, P.; Colla, M.-S.; Orekhov, A.; Idrissi, H.; Haye, E.; Pardoen, T.; Lucas, S. url  doi
openurl 
  Title Tailoring Mechanical Properties of a-C:H:Cr Coatings Type A1 Journal Article
  Year 2023 Publication Coatings Abbreviated Journal Coatings  
  Volume 13 Issue 12 Pages 2084  
  Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;  
  Abstract The development of coatings with tunable performances is critical to meet a wide range of technological applications each one with different requirements. Using the plasma-enhanced chemical vapor deposition (PECVD) process, scientists can create hydrogenated amorphous carbon coatings doped with metal (a-C:H:Me) with a broad range of mechanical properties, varying from those resembling polymers to ones resembling diamond. These diverse properties, without clear relations between the different families, make the material selection and optimization difficult but also very rich. An innovative approach is proposed here based on projected performance indices related to fracture energy, strength, and stiffness in order to classify and optimize a-C:H:Me coatings. Four different a-C:H:Cr coatings deposited by PECVD with Ar/C2H2 discharge under different bias voltage and pressures are investigated. A path is found to produce coatings with a selective critical energy release rate between 5–125 J/m2 without compromising yield strength (1.6–2.7 GPa) and elastic limit (≈0.05). Finally, fine-tuned coatings are categorized to meet desired applications under different testing conditions.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001136013600001 Publication Date 2023-12-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2079-6412 ISBN Additional Links UA library record; WoS full record  
  Impact Factor Times cited Open Access  
  Notes Walloon region under the PDR FNRS, C 62/5—PDR/OL 33677636 ; Belgian National Fund for Scientific Research, CDR—J.0113.20 ; National Fund for Scientific Reaserch; Approved Most recent IF: NA  
  Call Number EMAT @ emat @c:irua:202390 Serial 8982  
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Author (up) Bagiński, M.; Pedrazo-Tardajos, A.; Altantzis, T.; Tupikowska, M.; Vetter, A.; Tomczyk, E.; Suryadharma, R.N.S.; Pawlak, M.; Andruszkiewicz, A.; Górecka, E.; Pociecha, D.; Rockstuhl, C.; Bals, S.; Lewandowski, W. url  doi
openurl 
  Title Understanding and Controlling the Crystallization Process in Reconfigurable Plasmonic Superlattices Type A1 Journal article
  Year 2021 Publication Acs Nano Abbreviated Journal Acs Nano  
  Volume Issue Pages acsnano.0c09746  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)  
  Abstract The crystallization of nanomaterials is a primary source of solid-state, photonic structures. Thus, a detailed understanding of this process is of paramount importance for the successful application of photonic nanomaterials in emerging optoelectronic technologies. While colloidal crystallization has been thoroughly studied, for example, with advanced in situ electron microscopy methods, the noncolloidal crystallization (freezing) of nanoparticles (NPs) remains so far unexplored. To fill this gap, in this work, we present proof-of principle experiments decoding a crystallization of reconfigurable assemblies of NPs at a solid state. The chosen material corresponds to an excellent testing bed, as it enables both in situ and ex situ investigation using X-ray diffraction (XRD), transmission electron microscopy (TEM), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), atomic force microscopy (AFM), and optical spectroscopy in visible and ultraviolet range (UV−vis) techniques. In particular, ensemble measurements with small-angle XRD highlighted the dependence of the correlation length in the NPs assemblies on the number of heating/cooling cycles and the rate of cooling. Ex situ TEM imaging further supported these results by revealing a dependence of domain size and structure on the sample preparation route and by showing we can control the domain size over 2 orders of magnitude. The application of HAADF-STEM tomography, combined with in situ thermal control, provided three-dimensional single-particle level information on the positional order evolution within assemblies. This combination of real and reciprocal space provides insightful information on the anisotropic, reversibly reconfigurable assemblies of NPs. TEM measurements also highlighted the importance of interfaces in the polydomain structure of nanoparticle solids, allowing us to understand experimentally observed differences in UV−vis extinction spectra of the differently prepared crystallites. Overall, the obtained results show that the combination of in situ heating HAADF-STEM tomography with XRD and ex situ TEM techniques is a powerful approach to study nanoparticle freezing processes and to reveal the crucial impact of disorder in the solid-state aggregates of NPs on their plasmonic properties.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000634569100101 Publication Date 2021-02-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1936-0851 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 13.942 Times cited 10 Open Access OpenAccess  
  Notes Ministerstwo Nauki i Szkolnictwa Wyzszego, 0112/DIA/2019/48 ; European Commission, 731019 E171000009 (EUSMI) ; Narodowe Centrum Nauki, 2016/21/N/ST5/03356 ; Deutsche Forschungsgemeinschaft, RO 3640/12-1 ; Fundacja na rzecz Nauki Polskiej, First TEAM2016–2/15 ; European Research Council, 815128 (REALNANO) ; sygma; Approved Most recent IF: 13.942  
  Call Number EMAT @ emat @c:irua:175872 Serial 6673  
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