Malzeme Bilimi ve Nanoteknoloji Mühendisliği Bölümü / Department of Material Science & Nanotechnology Engineering

Permanent URI for this collectionhttps://gcris3.etu.edu.tr/handle/20.500.11851/279

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Now showing 1 - 20 of 107

Citation - WoS: 5
Citation - Scopus: 5
1,7-Diazaperylene in Organic Field Effect Transistors
(Wiley-V C H Verlag Gmbh, 2022) Yumusak, Cigdem; Mayr, Felix; Wielend, Dominik; Kahraman, Bilge; Kanbur, Yasin; Langhals, Heinz; Irimia-Vladu, Mihai
A thorough material characterization of 1,7-diazaperylene via multiple investigation techniques (cyclic voltammetry, photoluminescence, photoluminescence excitation, impedance spectroscopy) was performed to understand its applicability in organic electronic devices. The recorded data of this perylene derivative was placed in conjunction with the respective data of the parent perylene molecule, and the behavior of this novel compound in organic electronic devices (planar diodes and field effect transistors explained). Although no photovoltaic effect behavior was recorded in planar diodes where 1,7-diazaperylene was employed both as a donor as well as an acceptor, the perylene derivatives proves functional as dielectric layer in organic field effect transistors.
Citation - WoS: 62
Citation - Scopus: 58
Ab Initio Prediction of Semiconductivity in a Novel Two-Dimensional Sb2x3 (x= S, Se, Te) Monolayers With Orthorhombic Structure
(Nature Research, 2021) Bafekry, A.; Mortazavi, B.; Faraji, M.; Shahrokhi, M.; Shafique, A.; Jappor, H. R.; Feghhi, S. A. H.
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.
Citation - WoS: 14
Citation - Scopus: 15
An Alternative Method for Selective Metal Deposition Onto Flexible Materials
(Elsevier Science Sa, 2008) Demirci Sankır, Nurdan; Claus, Richard O.
in this article, a cost effective and simple method called line patterning is used for patterning of metal thin films deposited onto flexible substrates. Silver, gold and copper thin films have been deposited onto plastic substrates such as polyester, overhead transparency, polyimide and polyether imide and patterned via line patterning method. It was observed that the all metal thin films were electrically conductive and highly adhesive. Morphology of chemically deposited thin metal films was tested using scanning electron microscopy. Room temperature DC conductivities, current densities and power dissipation of these metal films have been investigated. (c) 2007 Elsevier B.V. All rights reserved.
Citation - WoS: 32
Citation - Scopus: 33
Band-Gap Engineering, Magnetic Behavior and Dirac-Semimetal Character in the Mosi2n4 Nanoribbon With Armchair and Zigzag Edges
(Iop Publishing Ltd, 2022) Bafekry, A.; Faraji, M.; Stampfl, C.; Sarsari, I. Abdolhosseini; Ziabari, A. Abdollahzadeh; Hieu, N. N.; Karbasizadeh, S.
Motivated by the recent successful formation of the MoSi2N4 monolayer (Hong et al 2020 Science 369, 670), the structural, electronic, and magnetic properties of MoSi2N4 nanoribbons (NRs) is investigated for the first time. The band structure calculations showed spin-polarization in zigzag edges and a non-magnetic semiconducting character in armchair edges. For armchair-edges, we identify an indirect to direct bandgap shift compared to the MoSi2N4 monolayer, and its energy gap increases with increasing NR width. Anisotropic electrical and magnetic behaviors are observed via band structure calculations at the zigzag and armchair edges, where, surprisingly, for one type of zigzag-edge configuration, we identifed a Dirac-semimetal character. The appearance of magnetism and Dirac-semimetal in MoSi2N4 ribbons can give rise to novel physical properties, which could be helpful in applications for next-generation electronic devices.
Citation - WoS: 28
Citation - Scopus: 29
Bifunctional Zno Nanowire/Znsno3 Heterojunction Thin Films for Photoelectrochemical Water Splitting and Photodetector Applications
(Elsevier B.V., 2022) Tuc Altaf C.; Coskun O.; Kumtepe A.; Sankır, Mehmet; Demirci Sankır, Nurdan
Robust, cost-effective, and scalable solution based chemical bath deposition and ultrasonic spray pyrolysis methods have been applied to fabricate one dimensional (1D) zinc oxide nanowire (ZnO NW) and zinc stannate (ZTO) heterojunction thin films to be employed in photoelectrochemical (PEC) water splitting and UV photodetector (PD) systems. PEC performance evaluation in a three-electrode cell confirmed the positive effect of ZTO on ZnO NW-based photoanode enhancing incident photon-to-current efficiency (IPCE%) two-folds of the pristine ZnO NW at 367 nm wavelength. Responsivity (Rs) and detectivity (D*) values of the pristine ZnO NW-based PD have been increased from 0.5 A.W?1 and 0.5 × 1012 Jones to 1.7 A.W?1 and 1.0 × 1012 Jones with ZTO layer, respectively. © 2022 Elsevier B.V.
Citation - WoS: 4
Citation - Scopus: 4
Co-Sensitization of Copper Indium Gallium Disulfide and Indium Sulfide on Zinc Oxide Nanostructures: Effect of Morphology in Electrochemical Carbon Dioxide Reduction
(American Chemical Society, 2024) Altaf, C.T.; Colak, T.O.; Karagoz, E.; Wang, J.; Liu, Y.; Demirci Sankır, Nurdan; Sankır, Mehmet
Recent advances in nanoparticle materials can facilitate the electro-reduction of carbon dioxide (CO2) to form valuable products with high selectivity. Copper (Cu)-based electrodes are promising candidates to drive efficient and selective CO2 reduction. However, the application of Cu-based chalcopyrite semiconductors in the electrocatalytic reduction of CO2 is still limited. This study demonstrated that novel zinc oxide (ZnO)/copper indium gallium sulfide (CIGS)/indium sulfide (InS) heterojunction electrodes could be used in effective CO2 reduction for formic acid production. It has been determined that Faradaic efficiencies for formic acid production using ZnO nanowire (NW) and nanoflower (NF) structures vary due to structural and morphological differences. A ZnO NW/CIGS/InS heterojunction electrode resulted in the highest efficiency of 77.2% and 0.35 mA cm-2 of current density at a −0.24 V (vs. reversible hydrogen electrode) bias potential. Adding a ZTO intermediate layer by the spray pyrolysis method decreased the yield of formic acid and increased the yield of H2. Our work offers a new heterojunction electrode for efficient formic acid production via cost-effective and scalable CO2 reduction. © 2024 The Authors. Published by American Chemical Society.
Citation - WoS: 60
Citation - Scopus: 41
Collider Aspects of Flavor Physics at High Q
(Springer, 2008) Lari, T.; Pape, L.; Porod, W.; Aguilar-Saavedra, J. A.; Allanach, B. C.; Burdman, G.; The ATLAS Collaboration; Sultansoy, Saleh
This chapter of the "Flavor in the era of LHC" workshop report discusses flavor-related issues in the production and decays of heavy states at the LHC at high momentum transfer Q, both from the experimental and the theoretical perspective. We review top quark physics, and discuss the flavor aspects of several extensions of the standard model, such as supersymmetry, little Higgs models or models with extra dimensions. This includes discovery aspects, as well as the measurement of several properties of these heavy states. We also present publicly available computational tools related to this topic.
Citation - WoS: 4
Citation - Scopus: 5
Color Octet Electron Search Potential of Fcc Based E-P Colliders
(Iop Publishing Ltd, 2017) Acar, Y. C.; Kaya, U.; Öner, Bilgehan Barış; Sultansoy, Saleh
Resonant production of color octet electrons, e(8), at the FCC based e-p colliders is analyzed. It is shown that e-FCC will cover much a wider region of e(8) masses compared to the LHC. Moreover, with the highest electron beam energy, the e(8) search potential of the e-FCC exceeds that of the FCC p-p collider. If e(8) is discovered earlier by the FCC p-p collider, e-FCC will give an opportunity to handle very important additional information. For example, the compositeness scale can be probed up to the hundreds of TeV region.
Citation - WoS: 24
Citation - Scopus: 25
Comparative Study of the Energetics of Ion Permeation in Kv1.2 and Kcsa Potassium Channels
(Cell Press, 2011) Baştuğ, Turgut; Kuyucak, Serdar
Biological ion channels rely on a multi-ion transport mechanism for fast yet selective permeation of ions. The crystal structure of the KcsA potassium channel provided the first microscopic picture of this process. A similar mechanism is assumed to operate in all potassium channels, but the validity of this assumption has not been well investigated. Here, we examine The energetics of ion permeation in Shaker Kv1.2 and KcsA channels, which exemplify the six-transmembrane voltage-gated and two-transmembrane inward-rectifier channels. We study the feasibility of binding a third ion to the filter and the concerted motion of ions in the channel by constructing the potential of mean force for K+ ions in various configurations. For both channels, we find that a pair of K+ ions can move almost freely within the filter, but a relatively large free-energy barrier hinders the K+ ion from stepping outside the filter. We discuss the effect of the CMAP dihedral energy correction that was recently incorporated into the CHARMM force field on ion permeation dynamics.
Citation - WoS: 22
Citation - Scopus: 26
Controlled Drug Release Behavior of Metformin Hydrogen Chloride From Biodegradable Films Based on Chitosan/Poly(ethylene Glycol) Methyl Ether Blend
(ELSEVIER, 2020-01) Sarwar, M. Sohail; Ghaffar, Abdul; Islam, Atif; Yasmin, Farhat; Oluz, Zehra; Tuncel, Eylül; Duran, Hatice; Qaiser, Asif Ali
In this study, novel smart drug release films were prepared by blending chitosan with polyethylene glycol methyl ether (PEGME), also named as methoxy polyethylene glycol (mPEG), for controlled drug release applications. The polymeric films were characterized by Fourier transform infra-red for functional groups analysis, scanning electron microscopy for morphology and X-ray photoelectron spectroscopy for chemical and surface analysis followed by mechanical and thermal analysis. The mechanical properties showed that with the addition of PEGME (40%), the tensile strength and elongation break were increased up to 34.14 MPa and 26.40%, respectively as compared to the controlled sample (without PEGME). The developed biodegradable films were tested for Metformin hydrogen chloride release ability at a particular rate in phosphate buffer saline solution at pH 7.4. The results showed that chitosan/PEGME blends could be employed for controlled drug release and other biomedical applications. (C) 2017 The Authors. Production and hosting by Elsevier B.V. on behalf of King Saud University.
Citation - WoS: 13
Citation - Scopus: 14
Cspbbr3 and Cs4pbbr6-Cspbbr3 Composite Perovskite Sensitization of 3d-Zno Nanostructures for Enhanced Photoluminescence Emission
(Elsevier, 2021) Altaf, Çiğdem Tuç; Abdullayeva, Nazrin; Sankır, Mehmet; Sankır, Nurdan Demirci
This study reports a seeding-layer free synthesis of nanostructured three-dimensional zinc oxide (3D-ZnO) thin films via a simple and cost-effective chemical bath deposition method (CBD) followed by their sensitization with inorganic perovskite halide semiconductors for luminescence-based applications. The emission abilities of pristine ZnO nanostructures have been enhanced with the incorporation of CsPbBr3 in the cubic crystal phase, which is proven to be a highly stable member of the inorganic halide perovskite family. Additionally, the transformation of CsPbBr3 nanocrystals into Cs4PbBr6-CsPbBr3 composite structure has been attained by altering the (i) CsBr content and (ii) crystallization temperature during the perovskite synthesis step, resulting in a remarkable luminescence increase for the overall structure by -17 folds. A detailed evaluation of defect contents and carrier lifetimes of pristine and perovskite deposited ZnO thin films have been conducted via time-resolved photoluminescence spectroscopy showing an improved electron transfer especially for Cs4PbBr6-CsPbBr3 deposited ZnO thin films.
Citation - WoS: 5
Citation - Scopus: 7
Dealloyed Ruthenium Film Catalysts for Hydrogen Generation From Chemical Hydrides
(MDPI AG, 2017) Serin, Ramis B.; Abdullayeva, Nazrin; Sankır, Mehmet
Thin-film ruthenium (Ru) and copper (Cu) binary alloys have been prepared on a Teflon™ backing layer by cosputtering of the precious and nonprecious metals, respectively. Alloys were then selectively dealloyed by sulfuric acid as an etchant, and their hydrogen generation catalysts performances were evaluated. Sputtering time and power of Cu atoms have been varied in order to tailor the hydrogen generation performances. Similarly, dealloying time and the sulfuric acid concentration have also been altered to tune the morphologies of the resulted films. A maximum hydrogen generation rate of 35 mL min-1 was achieved when Cu sputtering power and time were 200 W and 60 min and while acid concentration and dealloying time were 18 M and 90 min, respectively. It has also been demonstrated that the Ru content in the alloy after dealloying gradually increased with the increasing the sputtering power of Cu. After 90 min dealloying, the Ru to Cu ratio increased to about 190 times that of bare alloy. This is the key issue for observing higher catalytic activity. Interestingly, we have also presented template-free nanoforest-like structure formation within the context of one-step alloying and dealloying used in this study. Last but not least, the long-time hydrogen generation performances of the catalysts system have also been evaluated along 3600 min. During the first 600 min, the catalytic activity was quite stable, while about 24% of the catalytic activity decayed after 3000 min, which still makes these systems available for the development of robust catalyst systems in the area of hydrogen generation. © 2017 by the authors.
Citation - WoS: 26
Citation - Scopus: 27
Decoration of 3d Zno Nanoelectrodes With Cuins2 for Solar Water Splitting
(Elsevier B.V., 2019) Altaf, Çigdem Tuç; Yolacan, Demet; Demirci Sankır, Nurdan
This study reports the decoration of zinc oxide (ZnO) nanosheets with copper indium sulfide (CuInS2) via sequential metal deposition and post sulfurization methods for photoelectrochemical solar cell application. The three dimensional (3D) ZnO nanosheets are hydrothermally grown on conductive glass substrates by chemical bath deposition. Then, copper/indium metallic alloy is deposited via magnetron sputtering and annealed at high temperature in the presence of elemental sulfur to form CuInS2 absorber on the surface of 3D nanosheets. Photoelectrochemical measurements indicate that the decoration of CuInS2 layer over the ZnO nanosheets results in significant increase in the photocurrent density to 28 mA cm?2 (at 0.5 V vs Ag/AgCl) leading a remarkable amount of hydrogen generation during solar water splitting process, 1387 ?mol measured at 0 V vs Ag/AgCl under 1 sun-illumination for 4 h. © 2018 Elsevier B.V.
Design and Production of Mesh Patterned Photoelectrode With Maskless Laser Lithography and Device Performance of Perovskite Derived/Zno Nras Based Photodetector
(Springer, 2024) Eroğlu, Ayşe Nur; Altaf, Çiğdem Tuç; Demirci Sankır, Nurdan; Sankır, Mehmet
This study reports the design and fabrication of environmentally friendly, portable, robust, and stable self-powered photoelectrochemical photodetector (PEC-PD) devices based on the heterojunction of ZnO nanorod arrays (NRA) in a mesh pattern and inorganic halide perovskites (IHP). First, the effects of distance between the center of lines in a mesh pattern on the material properties and device performance were revealed. The mesh patterned ZnO NRAs-based PEC-PD device exhibited a fast response time (tau rise/tau decay = 100/75 ms) under UV-light illumination with 367 nm of wavelength at no applied bias. The best-performing mesh pattern was then used as a sub-layer for lead-based CsPbBr3-CsPb2Br5 dual-phase and lead-free Cs2AgBiBr6 double perovskite to construct self-powered p-n junction and PEC-PD devices. Upon the deposition of Cs2AgBiBr6, the maximum photocurrent value was enhanced about 13.65 times as compared to mesh patterned pristine ZnO NRAs under AM 1.5 illumination at + 5 V of applied potential. Responsivity (RS) and Detectivity (D*) values of the mesh patterned pristine ZnO NRAs-based PD have been increased from 0.24 mAW-1 and 3.0 x 108 Jones to 3.08 mAW-1 and 7.63 x 108 Jones with Cs2AgBiBr6 layer, respectively. Furthermore, 69.18 mAW-1 of RS and 1.71 x 1010 Jones of D* value have been observed at 382 nm wavelength and + 5 V for mesh patterned ZnO NRAs/Cs2AgBiBr6 photoelectrode.
Citation - WoS: 14
Citation - Scopus: 15
Design of Enzyme-Immobilized Polymer Brush-Grafted Magnetic Nanoparticles for Efficient Nematicidal Activity
(Royal Soc Chemistry, 2015) Butt, A.; Farrukh, A.; Ghaffar, A.; Duran, H.; Oluz, Z.; Rehman, H. ur; Yameen, B.
Parasitic nematodes not only cause deadly diseases in plants and animals but also adversely affect agricultural industry and global health, particularly in developing countries. In this study, we planned to combine the concept of enzyme immobilization with nanotechnology to develop magnetic nanoparticles (MNPs) with efficient nematicidal activity in water. A novel nematicidal platform was developed by immobilizing protease (from Streptomyces griseus) on the surface of polymer brush-grafted magnetic nanoparticles (MNPs-PGMA-Pro). For comparison, a monolayer-based nematicidal platform was also developed by functionalizing protease on the surface of glutaraldehyde-functionalized MNPs (MNPs-GA-Pro). MNPs-PGMA-Pro particles show enhanced enzyme activity and stability over a wide range of temperature and pH, as compared to MNPs-GA-Pro. Polymer brush- and monolayer-based protease-functionalized MNPs exhibit superior enzyme activity when compared to the free enzyme. When tested for nematicidal activity against parasitic nematodes (Haemonchus contortus), the polymer brush- based platform retained higher activity over 7 cycles of magnetic separation. The reported platforms can be prospectively employed for water treatment, whereas their reusability over many remediation cycles due to facile magnetic separation promises a substantially reduced treatment cost.
Citation - WoS: 3
Citation - Scopus: 3
Dialoxygenation: a Preclinical Trial for Transforming the Artificial Kidney Into an Oxygenator
(Lippincott Williams & Wilkins, 2025) Karacanoglu, Dilek; Bedir, Esra; Nakip, Ozlem Saritas; Kesici, Selman; Duran, Hatice; Bayrakci, Benan
Critically ill patients sometimes require tandem application of extracorporeal membrane oxygenation (ECMO) and continuous renal replacement therapy (CRRT) which is easier and cheaper. We aimed to transform the kidney membrane into a lung membrane by adding hydrogen peroxide (H2O2) to the dialysate as the oxygen source. A solution containing H2O2 and a dialysate fluid mixture was used as the final dialysate. Starting with 100% H2O2 solution and gradually reducing the volume of H2O2, respectively: 50%, 10%, 5%, 4%, 3%, 2%, and 1%. PRISMAFLEX system, Prismaflex M60 set and a bag of packed red blood cells (pRBCs) were the prototype. blood flow rate was about 40 ml/minute and the dialysis rate was about 200 ml/m2/minute/1.73 m2. blood sampling times were; at the beginning (T0), at 15th (T1), 30th (T2), 60th (T3) minutes. Amongst eight attempts H2O2 concentration that increased the partial oxygen pressure (pO2) level significantly in a reasonable period, without any bubbles, was 3%. Methemoglobinemia was not observed in any trial. After the test with 3%, H2O2 in the dialysate fluid decreased progressively without any H2O2 detection at post-membrane blood. Three percent H2O2 solution is sufficient and safe for oxygenation in CRRT systems. With this new oxy-dialysate solution, both pulmonary and renal replacement can be possible via a single membrane in a simpler manner.
Citation - WoS: 28
Citation - Scopus: 30
Dijet Azimuthal Correlations and Conditional Yields in Pp and P+pb Collisions at Snn =5.02 Tev With the Atlas Detector
(American Physical Society, 2019) The ATLAS Collaboration; Sultansoy, Saleh
This paper presents a measurement of forward-forward and forward-central dijet azimuthal angular correlations and conditional yields in proton-proton (pp) and proton-lead (p+Pb) collisions as a probe of the nuclear gluon density in regions where the fraction of the average momentum per nucleon carried by the parton entering the hard scattering is low. In these regions, gluon saturation can modify the rapidly increasing parton distribution function of the gluon. The analysis utilizes 25pb-1 of pp data and 360μb-1 of p+Pb data, both at sNN=5.02 TeV, collected in 2015 and 2016, respectively, with the ATLAS detector at the Large Hadron Collider. The measurement is performed in the center-of-mass frame of the nucleon-nucleon system in the rapidity range between -4.0 and 4.0 using the two highest transverse-momentum jets in each event, with the highest transverse-momentum jet restricted to the forward rapidity range. No significant broadening of azimuthal angular correlations is observed for forward-forward or forward-central dijets in p+Pb compared to pp collisions. For forward-forward jet pairs in the proton-going direction, the ratio of conditional yields in p+Pb collisions to those in pp collisions is suppressed by approximately 20%, with no significant dependence on the transverse momentum of the dijet system. No modification of conditional yields is observed for forward-central dijets. © 2019 CERN.
Citation - WoS: 23
Citation - Scopus: 84
A Dirac-Semimetal Two-Dimensional Ben4: Thickness-Dependent Electronic and Optical Properties
(Aip Publishing, 2021) Bafekry, A.; Stampfl, C.; Faraji, M.; Yagmurcukardes, M.; Fadlallah, M. M.; Jappor, H. R.; Ghergherehchi, M.
Motivated by the recent experimental realization of a two-dimensional (2D) BeN4 monolayer, in this study we investigate the structural, dynamical, electronic, and optical properties of a monolayer and few-layer BeN4 using first-principles calculations. The calculated phonon band dispersion reveals the dynamical stability of a free-standing BeN4 layer, while the cohesive energy indicates the energetic feasibility of the material. Electronic band dispersions show that monolayer BeN4 is a semi-metal whose conduction and valence bands touch each other at the Sigma point. Our results reveal that increasing the layer number from single to six-layers tunes the electronic nature of BeN4. While monolayer and bilayer structures display a semi-metallic behavior, structures thicker than that of three-layers exhibit a metallic nature. Moreover, the optical parameters calculated for monolayer and bilayer structures reveal that the bilayer can absorb visible light in the ultraviolet and visible regions better than the monolayer structure. Our study investigates the electronic properties of Dirac-semimetal BeN4 that can be an important candidate for applications in nanoelectronic and optoelectronic. Published under an exclusive license by AIP Publishing.
Citation - WoS: 8
Citation - Scopus: 9
Down Type Isosinglet Quarks in Atlas
(Springer, 2008) Mehdiyev, R.; Siodmok, A.; Sultansoy, Saleh; Ünel, Gökhan
We evaluate the discovery reach of the ATLAS experiment for down type isosinglet quarks, D, using both their neutral and charged decay channels, namely the process pp -> D (D) over bar +X with subsequent decays resulting in 2l + 2j +E-T, 3l + 2j + E-T and 2l + 4j final states. The integrated luminosity required for observation of a heavy quark is estimated for a mass range between 600 and 1000 GeV using the combination of results from different search channels.
Citation - WoS: 38
Citation - Scopus: 39
Effect of Adsorption and Substitutional B Doping at Different Concentrations on the Electronic and Magnetic Properties of a Beo Monolayer: a First-Principles Study
(Royal Soc Chemistry, 2021) Bafekry, A.; Faraji, M.; Fadlallah, M. M.; Hoat, D. M.; Khatibani, A. Bagheri; Sarsari, I. Abdolhosseini; Ghergherehchi, M.
The 2D form of the BeO sheet has been successfully prepared (Hui Zhang et al., ACS Nano, 2021, 15, 2497). Motivated by these exciting experimental results on the 2D layered BeO structure, we studied the effect of the adsorption of B atoms on BeO (B@BeO) and substitutional B atoms (B-BeO) at the Be site at different B concentrations. We investigated the structural stability and the mechanical, electronic, magnetic, and optical properties of the mentioned structures using first-principles calculations. We found out that hexagonal BeO monolayers with adsorbed and dopant B atoms have different mechanical stabilities at different concentrations. B@BeO and B-BeO monolayers are brittle structures, and B@BeO structures are more rigid than B-BeO monolayers (at the same B concentration). The adsorption and the formation energy per B atom decrease as the B concentration increases. In comparison, the work function increases when increasing the B concentration. The work function of B@BeO is higher than the corresponding value of B-BeO (at the same B concentration). The magnetic moment linearly increases as the B concentration increases. BeO is a semiconductor with an indirect bandgap of 5.3 eV. The B@BeO and B-BeO structures are semiconductors, except for 3B-BeO (14.2% doped concentration), which is a metal. The bandgap is 1.25 eV for most of the adsorbed atom concentrations. For B-BeO, the bandgap decreases to zero at a concentration of 14.2%. The bandgap of the B-BeO monolayer at different B concentrations is smaller than the corresponding values of the B@BeO monolayer, which indicates that B substitutional doping has a greater effect on the electronic structure of the BeO monolayer than B adsorption doping. We investigated the optical properties, including the dielectric function and absorption coefficient. The results indicate good optical absorption in the range of infrared and ultraviolet energies for the B adsorbed and doped BeO monolayer.

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