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	Author	Bafekry, A.; Shayesteh, S.F.; Peeters, F.M.
	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	Bafekry, A.; Ghergherehchi, M.; Shayesteh, S.F.; Peeters, F.M.
	Title	Adsorption of molecules on C₃N nanosheet : a first-principles calculations			Type	A1 Journal article
	Year	2019	Publication	Chemical physics	Abbreviated Journal	Chem Phys
	Volume	526	Issue	526	Pages	110442
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Using first-principles calculations we investigate the interaction of various molecules, including H-2, N-2, CO, CO2, H2O, H2S, NH3, CH4 with a C3N nanosheet. Due to the weaker interaction between H-2, N-2, CO, CO2, H2O, H2S, NH3, and CH4 molecules with C3N, the adsorption energy is small and does not yield any significant distortion of the C3N lattice and the molecules are physisorbed. Calculated charge transfer shows that these molecules act as weak donors. However, adsorption of O-2, NO, NO2 and SO2 molecules are chemisorbed, they receive electrons from C3N and act as a strong acceptor. They interact strongly through hybridizing its frontier orbitals with the p-orbital of C3N, modifying the electronic structure of C3N. Our theoretical studies indicate that C3N-based sensor has a high potential for O-2, NO, NO2 and SO2 molecules detection.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000481606000006	Publication Date	2019-07-09
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0301-0104	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.767	Times cited	46	Open Access
	Notes	; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF-2017R1A2B2011989). In addition, this work was supported by the FLAG-ERA project 2DTRANS and the Flemish Science Foundation (FWO-Vl). ;			Approved	Most recent IF: 1.767
	Call Number	UA @ admin @ c:irua:161779			Serial	5405
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	Author	Bafekry, A.; Mortazavic, B.; Shayesteh, S.F.
	Title	Band gap and magnetism engineering in Dirac half-metallic Na₂C nanosheet via layer thickness, strain and point defects			Type	A1 Journal article
	Year	2019	Publication	Journal of magnetism and magnetic materials	Abbreviated Journal	J Magn Magn Mater
	Volume	491	Issue	491	Pages	165565
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Na2C is a novel two-dimensional material with Dirac Half-metal (DHM) characteristic, exhibiting a combination of single-spin massless Dirac fermions and half-semimetal. In this paper based on the first-principles calculations, we studied the mechanical, electronic, magnetic and optical properties of Na2C nanosheet. The elastic modulus of Na2C was measured to 18.5 N/m and isotropic, whereas it shows anisotropic tensile strengths of 2.85 and 2.04 N/m, for the loading along the zigzag and armchair directions, respectively. We found that Na2C, is a DHM with band gap of 0.7 eV in the up-spin channel and has 2 mu(B) magnetic moment per unit cell. In addition, we investigated the effects of number of atomic layers (thickness), electric field and strain on the possibility of further tuning of the electronic and magnetic properties of Na2C. Our calculations show that by increasing the number of layers from monolayer to bulk, a transition from DHM to ferromagnetic metal occurs with a high magnetic moments in the range of 16-30 mu(B). With applying an electric field on the Na2C bilayer (within the ferromagnetic and anti-ferromagnetic orders), energy band gap is slightly increased. In addition our results indicate that the electronic structure can be significantly modified by applying the mechanical straining. In this regard, under the biaxial strain (from 0% to – 8%) or large uniaxial strains (> – 6%), we observed the DHM to ferromagnetic-metal transition. Moreover, vacancy defects and atom substitutions can also effect the electronic and magnetic properties of Na2C nanosheet. Defective Na2C with single and double vacancies, was found to show the metallic response. With various atom substitutions this nanosheet exhibits; ferromagnetic-metal (Si and Be) with 5.2 and 3 mu(B); dilute-magnetic semiconductor (B and N) with 3 and 7 mu(B) magnetic moments, respectively. In the case of B or N atoms replacing the native C atom, the down-spin channel yields about 1 eV band gap. Interestingly, replacing the Na atoms in the native Na2C lattice with the Li can result in the formation of magnetic topological insulator phase with nontrivial band gap in the down-spin channel (25 meV and 0.15 eV) and up-spin channel (0.75 eV), in addition exhibit 8 mu(B) magnetic moment in the ground state.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000486396100010	Publication Date	2019-07-15
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0304-8853	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.63	Times cited	13	Open Access
	Notes	; B. M. appreciates 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). We acknowledge OpenMX team for OpenMX code. ;			Approved	Most recent IF: 2.63
	Call Number	UA @ admin @ c:irua:163697			Serial	5408
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	Author	Bafekry, A.; Stampfl, C.; Shayesteh, S.F.; Peeters, F.M.
	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	Bafekry, A.; Shayesteh, S.F.; Peeters, F.M.
	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	Bafekry, A.; Ghergherehchi, M.; Shayesteh, S.F.
	Title	Tuning the electronic and magnetic properties of antimonene nanosheets via point defects and external fields: first-principles calculations			Type	A1 Journal article
	Year	2019	Publication	Physical chemistry, chemical physics	Abbreviated Journal	Phys Chem Chem Phys
	Volume	21	Issue	20	Pages	10552-10566
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Defects are inevitably present in materials, and their existence in a material strongly affects its fundamental physical properties. We have systematically investigated the effects of surface adsorption, substitutional impurities, defect engineering, an electric field and strain engineering on the structural, electronic and magnetic properties of antimonene nanosheets, using spin-polarized density functional calculations based on first-principles. The adsorption or substitution of atoms can locally modify the atomic and electronic structures as well as induce a variety of electronic behaviors including metal, half-metal, ferromagnetic metal, dilute magnetic semiconductor and spin-glass semiconductor. Our calculations show that the presence of typical defects (vacancies and Stone-Wales defect) in antimonene affects the geometrical symmetry as well as the band gap in the electronic band structure and induces magnetism to antimonene. Moreover, by applying an external electric field and strain (uniaxial and biaxial), the electronic structure of antimonene can be easily modified. The calculation results presented in this paper provide a fundamental insight into the tunable nature of the electronic properties of antimonene, supporting its promise for use in future applications.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000476561000031	Publication Date	2019-04-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1463-9076; 1463-9084	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.123	Times cited	17	Open Access
	Notes	; ;			Approved	Most recent IF: 4.123
	Call Number	UA @ admin @ c:irua:161945			Serial	5430
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	Author	Bafekry, A.; Stampfl, C.; Shayesteh, S.F.
	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	Bafekry, A.; Stampfl, C.; Ghergherehchi, M.; Shayesteh, S.F.
	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	Bafekry, A.; Shayesteh, S.F.; Ghergherehchi, M.; Peeters, F.M.
	Title	Tuning the bandgap and introducing magnetism into monolayer BC3 by strain/defect engineering and adatom/molecule adsorption			Type	A1 Journal article
	Year	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	Bafekry, A.; Shayesteh, S.F.; Peeters, F.M.
	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	Bafekry, A.; Stampfl, C.; Ghergherehchi, M.
	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	Bafekry, A.; Stampfl, C.; Akgenc, B.; Ghergherehchi, M.
	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	Bafekry, A.; Stampfl, C.; Peeters, F.M.
	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	Bafekry, A.; Yagmurcukardes, M.; Shahrokhi, M.; Ghergherehchi, M.
	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	Bafekry, A.; Stampfl, C.; Peeters, F.M.
	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	Bafekry, A.; Stampfl, C.; Akgenc, B.; Mortazavi, B.; Ghergherehchi, M.; Nguyen, C.V.
	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	Obeid, M.M.; Stampfl, C.; Bafekry, A.; Guan, Z.; Jappor, H.R.; Nguyen, C., V; Naseri, M.; Hoat, D.M.; Hieu, N.N.; Krauklis, A.E.; Tuan V Vu; Gogova, D.
	Title	First-principles investigation of nonmetal doped single-layer BiOBr as a potential photocatalyst with a low recombination rate			Type	A1 Journal article
	Year	2020	Publication	Physical Chemistry Chemical Physics	Abbreviated Journal	Phys Chem Chem Phys
	Volume	22	Issue	27	Pages	15354-15364
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Nonmetal doping is an effective approach to modify the electronic band structure and enhance the photocatalytic performance of bismuth oxyhalides. Using density functional theory, we systematically examine the fundamental properties of single-layer BiOBr doped with boron (B) and phosphorus (P) atoms. The stability of the doped models is investigated based on the formation energies, where the substitutional doping is found to be energetically more stable under O-rich conditions than under Bi-rich ones. The results showed that substitutional doping of P atoms reduced the bandgap of pristine BiOBr to a greater extent than that of boron substitution. The calculation of the effective masses reveals that B doping can render the electrons and holes of pristine BiOBr lighter and heavier, respectively, resulting in a slower recombination rate of photoexcited electron-hole pairs. Based on the results of HOMO-LUMO calculations, the introduction of B atoms tends to increase the number of photocatalytically active sites. The top of the valence band and the conduction band bottom of the B doped BiOBr monolayer match well with the water redox potentials in an acidic environment. The absorption spectra propose that B(P) doping causes a red-shift. Overall, the results predict that nonmetal-doped BiOBr monolayers have a reduced bandgap, a slow recombination rate, more catalytically active sites, enhanced optical absorption edges, and reduced work functions, which will contribute to superior photocatalytic performance.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000549894000018	Publication Date	2020-06-16
	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 was partially supported by the financial support from the Natural Science Foundation of China (Grant No. 11904203) and the Fundamental Research Funds of Shandong University (Grant No. 2019GN065). ;			Approved	Most recent IF: 3.3; 2020 IF: 4.123
	Call Number	UA @ admin @ c:irua:171235			Serial	6522
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	Author	Bafekry, A.; Obeid, M.; Nguyen, C.; Bagheri Tagani, M.; Ghergherehchi, M.
	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	Bafekry, A.
	Title	Graphene-like BC₆N single-layer: tunable electronic and magnetic properties via thickness, gating, topological defects, and adatom/molecule			Type	A1 Journal article
	Year	2020	Publication	Physica E-Low-Dimensional Systems & Nanostructures	Abbreviated Journal	Physica E
	Volume	118	Issue		Pages	113850-15
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	By using density functional theory-based first-principles calculations, we investigate the structural, electronic, optical, and transport properties of pristine single-layer BC6N. Under different external actions and functionalization. Increasing the thickness of the structure results in a decrease of the band gap. Applying a perpendicular electric field decreases the band gap and a semiconductor-to-topological insulator transition is revealed. Uniaxial and biaxial strains of +8% result in a semiconductor-to-metal transition. Nanoribbons of BC6N having zigzag edge with even (odd) values of widths, become metal (semiconductor), while the armchair edge nanoribbons exhibit robust semiconducting behavior. In addition, we systematically investigate the effect of surface adatom and molecule, substitutional impurity and defect engineering on the electronic properties of single-layer BC6N and found transitions from metal to half-metal, to ferromagnetic metal, to dilute magnetic semiconductor, and even to spin-glass semiconductor. Furthermore we found that, topological defects including vacancies and Stone–Wales type, induce magnetism in single-layer BC6N.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000515321700032	Publication Date	2019-12-04
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1386-9477	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.3	Times cited	30	Open Access
	Notes	; ;			Approved	Most recent IF: 3.3; 2020 IF: 2.221
	Call Number	UA @ admin @ c:irua:169750			Serial	6530
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	Author	Nguyen, H.T.T.; Obeid, M.M.; Bafekry, A.; Idrees, M.; Vu, T.V.; Phuc, H., V; Hieu, N.N.; Le Hoa, T.; Amin, B.; Nguyen, C., V
	Title	Interfacial characteristics, Schottky contact, and optical performance of a graphene/Ga2SSe van der Waals heterostructure: Strain engineering and electric field tunability			Type	A1 Journal article
	Year	2020	Publication	Physical Review B	Abbreviated Journal	Phys Rev B
	Volume	102	Issue	7	Pages	075414-10
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Two-dimensional graphene-based van der Waals heterostructures have received considerable interest because of their intriguing characteristics compared with the constituent single-layer two-dimensional materials. Here, we investigate the interfacial characteristics, Schottky contact, and optical performance of graphene/Ga2SSe van der Waals (vdW) heterostructure using first-principles calculations. The effects of stacking patterns, electric gating, and interlayer coupling on the interfacial properties of graphene/Ga2SSe heterostructures are also examined. Our results demonstrate that the Dirac cone of graphene is well preserved at the F point in all stacking patterns due to the weak vdW interactions, which keep the heterostructures feasible such that they can be obtained in further experiments. Moreover, depending on the stacking patterns, a small band gap of about 13-17 meV opens in graphene and has a high carrier mobility, indicating that the graphene/Ga2SSe heterostructures are potential candidates for future high-speed nanoelectronic applications. In the ground state, the graphene/Ga2SSe heterostructures form an n-type Schottky contact. The transformation from an n-type to a p-type Schottky contact or to an Ohmic contact can be forced by electric gating or by varying the interlayer coupling. Our findings could provide physical guidance for designing controllable Schottky nanodevices with high electronic and optical performances.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000557294500006	Publication Date	2020-08-07
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9969; 2469-9950	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.7	Times cited	12	Open Access
	Notes	; This research is funded by Vietnam National Foundation for Science and Technology Development (NAFOSTED) under Grant No. 103.01-2019.05. The authors declare that there are no conflicts of interest regarding the publication of this paper. ;			Approved	Most recent IF: 3.7; 2020 IF: 3.836
	Call Number	UA @ admin @ c:irua:171163			Serial	6549
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	Author	Bafekry, A.; Nguyen, C., V; Goudarzi, A.; Ghergherehchi, M.; Shafieirad, M.
	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	Bafekry, A.
	Title	Investigation of the effects of defects and impurities on nanostructures consisting of Group IV and V elements using First-principles calculations			Type	Doctoral thesis
	Year	2020	Publication		Abbreviated Journal
	Volume		Issue		Pages	126 p.
	Keywords	Doctoral thesis; Condensed Matter Theory (CMT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:168738			Serial	6554
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	Author	Bafekry, A.; Nguyen, C.; Obeid, M.M.; Ghergherehchi, M.
	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	Bafekry, A.; Van Nguyen, C.; Stampfl, C.; Akgenc, B.; Ghergherehchi, M.
	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	Bafekry, A.; Akgenc, B.; Ghergherehchi, M.; Peeters, F.M.
	Title	Strain and electric field tuning of semi-metallic character WCrCO₂ MXenes with dual narrow band gap			Type	A1 Journal article
	Year	2020	Publication	Journal Of Physics-Condensed Matter	Abbreviated Journal	J Phys-Condens Mat
	Volume	32	Issue	35	Pages	355504-355508
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Motivated by the recent successful synthesis of double-M carbides, we investigate structural and electronic properties of WCrC and WCrCO2 monolayers and the effects of biaxial and out-of-plane strain and electric field using density functional theory. WCrC and WCrCO2 monolayers are found to be dynamically stable. WCrC is metallic and WCrCO2 display semi-metallic character with narrow band gap, which can be controlled by strain engineering and electric field. WCrCO2 monolayer exhibits a dual band gap which is preserved in the presence of an electric field. The band gap of WCrCO2 monolayer increases under uniaxial strain while it becomes metallic under tensile strain, resulting in an exotic 2D double semi-metallic behavior. Our results demonstrate that WCrCO2 is a new platform for the study of novel physical properties in two-dimensional Dirac materials and which may provide new opportunities to realize high-speed low-dissipation devices.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000539375800001	Publication Date	2020-04-29
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0953-8984	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.7	Times cited	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 Flemish Science Foundation (FW0-Vl). ;			Approved	Most recent IF: 2.7; 2020 IF: 2.649
	Call Number	UA @ admin @ c:irua:169756			Serial	6616
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	Author	Bafekry, A.; Shojai, F.; Hoat, D.M.; Shahrokhi, M.; Ghergherehchi, M.; Nguyen, C.
	Title	The mechanical, electronic, optical and thermoelectric properties of two-dimensional honeycomb-like of XSb (X = Si, Ge, Sn) monolayers: a first-principles calculations			Type	A1 Journal article
	Year	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	Bafekry, A.; Akgenc, B.; Shayesteh, S.F.; Mortazavi, B.
	Title	Tunable electronic and magnetic properties of graphene/carbon-nitride van der Waals heterostructures			Type	A1 Journal article
	Year	2020	Publication	Applied Surface Science	Abbreviated Journal	Appl Surf Sci
	Volume	505	Issue		Pages	144450-144459
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	In this paper, we explore the electronic properties of C3N, C3N4 and C4N3 and graphene (Gr) van der Waals heterostructures by conducing extensive first-principles calculations. The acquired results show that these heterostructures can show diverse electronic properties, such as the metal (Gr on C3N), semiconductor with narrow band gap (Gr on C3N4) and ferromagnetic-metal (Gr on C4N3). We furthermore explored the effect of vacancies, atom substitution, topological, antisite and Stone-Wales defects on the structural and electronic properties of considered heterostructures. Our results show that the vacancy defects introduce localized states near the Fermi level and create a local magnetic moment. The Gr/C3N heterostructures with the single and double vacancy defects exhibit a ferromagnetic-metal, while Stone-Wales defects show an indirect semiconductor with the band gap of 0.2 eV. The effects of adsorption and insertion of O, C, Be, Cr, Fe and Co atoms on the electronic properties of Gr/C3N have been also elaborately studied. Our results highlight that the electronic and magnetic properties of garphene/carbon-nitride lateral heterostructures can be effectively modified by point defects and impurities.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000510846500052	Publication Date	2019-11-18
	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	6.7	Times cited	26	Open Access
	Notes	; ;			Approved	Most recent IF: 6.7; 2020 IF: 3.387
	Call Number	UA @ admin @ c:irua:167732			Serial	6638
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	Author	Bafekry, A.; Neek-Amal, M.
	Title	Tuning the electronic properties of graphene-graphitic carbon nitride heterostructures and heterojunctions by using an electric field			Type	A1 Journal article
	Year	2020	Publication	Physical Review B	Abbreviated Journal	Phys Rev B
	Volume	101	Issue	8	Pages	085417-10
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Integration of graphene-based two-dimensional materials is essential for nanoelectronics applications. Using density-functional theory, we systematically investigate the electronic properties of vertically stacked graphene-graphitic carbon nitrides (GE/GCN). We also studied the covalently lateral stitched graphene-graphitic carbon nitrides (GE-GCN heterojunctions). The effects of perpendicular electric field on the electronic properties of six different heterostructures, i.e., (i) one layer of GE on top of a layer of CnNm with (n, m) = (3,1), (3,4), and (4,3) and (ii) three heterostructures CnNm/Cn'Nm', where (n, m) not equal (n', m') are elucidated. The most important calculated features are (i) the systems GE/C3N4, C3N/C3N4, GE-C3N, GE-C4N3, and C3N-C3N4 exhibit semiconducting characteristics having small band gaps of Delta(0)=20, 250, 100, 100, 80 meV, respectively while (ii) the systems GE/C4N3, C3N/C4N3, and C3N-C4N3 show ferromagnetic-metallic properties. In particular, we found that, in semiconducting heterostructures, the band gap increases nontrivially with increasing the absolute value of the applied perpendicular electric field. This work is useful for designing heterojunctions and heterostructures made of graphene and other two-dimensional materials such as those proposed in recent experiments [X. Liu and M. C. Hersam Sci. Adv. 5, 6444 (2019)].
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000515659700007	Publication Date	2020-02-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9969; 2469-9950	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.7	Times cited	24	Open Access
	Notes	; ;			Approved	Most recent IF: 3.7; 2020 IF: 3.836
	Call Number	UA @ admin @ c:irua:167760			Serial	6640
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	Author	Bafekry, A.; Neek-Amal, M.; Peeters, F.M.
	Title	Two-dimensional graphitic carbon nitrides: strain-tunable ferromagnetic ordering			Type	A1 Journal article
	Year	2020	Publication	Physical Review B	Abbreviated Journal	Phys Rev B
	Volume	101	Issue	16	Pages	165407-165408
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Using first-principle calculations, we systematically study strain tuning of the electronic properties of two- dimensional graphitic carbon nitride nanosheets with empirical formula CnNm. We found the following: (i) the ferromagnetic ordered state in the metal-free systems (n, m) = (4,3), (10,9), and (14,12) remains stable in the presence of strain of about 6%. However, the system (9,7) loses its ferromagnetic ordering when increasing strain. This is due to the presence of topological defects in the (9,7) system, which eliminates the asymmetry between spin up and spin down of the p(z) orbitals when strain is applied. (ii) By applying uniaxial strain, a band gap opens in systems which are initially gapless. (iii) In semiconducting systems which have an initial gap of about 1 eV, the band gap is closed with applying uniaxial strain.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000523630200012	Publication Date	2020-04-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9969; 2469-9950	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.7	Times cited	22	Open Access
	Notes	; ;			Approved	Most recent IF: 3.7; 2020 IF: 3.836
	Call Number	UA @ admin @ c:irua:168560			Serial	6643
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	Author	Bafekry, A.; Shojaei, F.; Obeid, M.M.; Ghergherehchi, M.; Nguyen, C.; Oskouian, M.
	Title	Two-dimensional silicon bismotide (SiBi) monolayer with a honeycomb-like lattice: first-principles study of tuning the electronic properties			Type	A1 Journal article
	Year	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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