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	Author	Bafekry, A.; Faraji, M.; Fadlallah, M.M.; Mortazavi, B.; Ziabari, A.A.; Khatibani, A.B.; Nguyen, C., V; Ghergherehchi, M.; Gogova, D.
	Title	Point defects in a two-dimensional ZnSnN₂ nanosheet : a first-principles study on the electronic and magnetic properties			Type	A1 Journal article
	Year	2021	Publication	Journal Of Physical Chemistry C	Abbreviated Journal	J Phys Chem C
	Volume	125	Issue	23	Pages	13067-13075
	Keywords	A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
	Abstract	The reduction of dimensionality is a very effective way to achieve appealing properties in two-dimensional materials (2DMs). First-principles calculations can greatly facilitate the prediction of 2DM properties and find possible approaches to enhance their performance. We employed first-principles calculations to gain insight into the impact of different types of point defects (vacancies and substitutional dopants) on the electronic and magnetic properties of a ZnSnN2 (ZSN) monolayer. We show that Zn, Sn, and N + Zn vacancy-defected structures are p-type conducting, while the defected ZSN with a N vacancy is n-type conducting. For substitutional dopants, we found that all doped structures are thermally and energetically stable. The most stable structure is found to be B-doping at the Zn site. The highest work function value (5.0 eV) has been obtained for Be substitution at the Sn site. Li-doping (at the Zn site) and Be-doping (at the Sn site) are p-type conducting, while B-doping (at the Zn site) is n-type conducting. We found that the considered ZSN monolayer-based structures with point defects are magnetic, except those with the N vacancy defects and Be-doped structures. The ab initio molecular dynamics simulations confirm that all substitutionally doped and defected structures are thermally stable. Thus, our results highlight the possibility of tuning the magnetism in ZnSnN2 monolayers through defect engineering.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000664312500063	Publication Date	2021-06-03
	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		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 4.536
	Call Number	UA @ admin @ c:irua:179741			Serial	7012
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	Author	Bafekry, A.; Mortazavi, B.; Faraji, M.; Shahrokhi, M.; Shafique, A.; Jappor, H.R.; Nguyen, C.; Ghergherehchi, M.; Feghhi, S.A.H.
	Title	Ab initio prediction of semiconductivity in a novel two-dimensional Sb₂X₃ (X= S, Se, Te) monolayers with orthorhombic structure			Type	A1 Journal article
	Year	2021	Publication	Scientific Reports	Abbreviated Journal	Sci Rep-Uk
	Volume	11	Issue	1	Pages	10366
	Keywords	A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
	Abstract	Sb2S3 and Sb2Se3 are well-known layered bulk structures with weak van der Waals interactions. In this work we explore the atomic lattice, dynamical stability, electronic and optical properties of Sb2S3, Sb2Se3 and Sb2Te3 monolayers using the density functional theory simulations. Molecular dynamics and phonon dispersion results show the desirable thermal and dynamical stability of studied nanosheets. On the basis of HSE06 and PBE/GGA functionals, we show that all the considered novel monolayers are semiconductors. Using the HSE06 functional the electronic bandgap of Sb2S3, Sb2Se3 and Sb2Te3 monolayers are predicted to be 2.15, 1.35 and 1.37 eV, respectively. Optical simulations show that the first absorption coefficient peak for Sb2S3, Sb2Se3 and Sb2Te3 monolayers along in-plane polarization is suitable for the absorption of the visible and IR range of light. Interestingly, optically anisotropic character along planar directions can be desirable for polarization-sensitive photodetectors. Furthermore, we systematically investigate the electrical transport properties with combined first-principles and Boltzmann transport theory calculations. At optimal doping concentration, we found the considerable larger power factor values of 2.69, 4.91, and 5.45 for hole-doped Sb2S3, Sb2Se3, and Sb2Te3, respectively. This study highlights the bright prospect for the application of Sb2S3, Sb2Se3 and Sb2Te3 nanosheets in novel electronic, optical and energy conversion systems.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000656961400019	Publication Date	2021-05-14
	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	4.259	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 4.259
	Call Number	UA @ admin @ c:irua:179188			Serial	6965
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	Author	Bafekry, A.; Faraji, M.; Ziabari, A.A.; Fadlallah, M.M.; Nguyen, C., V; Ghergherehchi, M.; Feghhi, S.A.H.
	Title	A van der Waals heterostructure of MoS₂/MoSi₂N₄ : a first-principles study			Type	A1 Journal article
	Year	2021	Publication	New Journal Of Chemistry	Abbreviated Journal	New J Chem
	Volume	45	Issue	18	Pages	8291-8296
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Motivated by the successful preparation of MoSi2N4 monolayers in the last year [Y.-L. Hong et al., Science, 2020, 369, 670-674], we investigate the structural, electronic and optical properties of the MoS2/MoSi2N4 heterostructure (HTS). The phonon dispersion and the binding energy calculations refer to the stability of the HTS. The heterostructure has an indirect bandgap of 1.26 (1.84) eV using PBE (HSE06) which is smaller than the corresponding value of MoSi2N4 and MoS2 monolayers. We find that the work function of the MoS2/MoSi2N4 HTS is smaller than the corresponding value of its individual monolayers. The heterostructure structure can enhance the absorption of light spectra not only in the ultraviolet region but also in the visible region as compared to MoSi2N4 and MoS2 monolayers. The refractive index behaviour of the HTS can be described as the cumulative effect which is well described in terms of a combination of the individual effects (the refractive index of MoSi2N4 and MoS2 monolayers).
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000642436200001	Publication Date	2021-03-10
	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	3.269	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 3.269
	Call Number	UA @ admin @ c:irua:178300			Serial	6964
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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.; 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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	Author	Obeid, M.M.; Bafekry, A.; Rehman, S.U.; Nguyen, C., V.
	Title	A type-II GaSe/HfS₂ van der Waals heterostructure as promising photocatalyst with high carrier mobility			Type	A1 Journal article
	Year	2020	Publication	Applied Surface Science	Abbreviated Journal	Appl Surf Sci
	Volume	534	Issue		Pages	147607
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	In this paper, the electronic, optical, and photocatalytic properties of GaSe/HfS2 heterostructure are studied via first-principles calculations. The stability of the vertically stacked heterobilayers is validated by the binding energy, phonon spectrum, and ab initio molecular dynamics simulation. The results reveal that the most stable GaSe/HfS2 heterobilayer retains a type-II alignment with an indirect bandgap 1.40 eV. As well, the results also show strong optical absorption intensity in the studied heterostructure (1.8 x 10(5) cm(-1)). The calculated hole mobility is 1376 cm(2) V-1 s(-1), while electron mobility reaches 911 cm(2) V-1 s(-1) along the armchair and zigzag directions. By applying an external electric field, the bandgap and band offset of the designed heterostructure can be effectively modified. Remarkably, a stronger external electric field can create nearly free electron states in the vicinity of the bottom of the conduction band, which induces indirect-to-direct bandgap transition as well as a semiconductor-to-metal transition. In contrast, the electronic properties of GaSe/HfS2 heterostructure are predicted to be insensitive to biaxial strain. The current work reveals that GaSe/HfS2 heterostructure is a promising candidate as a novel photocatalytic material for hydrogen generation in the visible range.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000582367700045	Publication Date	2020-08-20
	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	4	Open Access
	Notes	; ;			Approved	Most recent IF: 6.7; 2020 IF: 3.387
	Call Number	UA @ admin @ c:irua:174301			Serial	6682
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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.; 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	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	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.; Yagmurcukardes, M.; Akgenc, B.; Ghergherehchi, M.; Nguyen, C.
	Title	Van der Waals heterostructures of MoS₂ and Janus MoSSe monolayers on graphitic boron-carbon-nitride (BC₃, C₃N, C₃N₄ and C₄N₃) nanosheets: a first-principles study			Type	A1 Journal article
	Year	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	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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