Graphene-like BC3 Research Articles

Photogalvanic effect in the armchair and zigzag photodetectors based on the graphene-like BC3 monolayer

The graphene-like BC3 monolayer has been experimentally prepared. In this paper, based on this BC3 monolayer, we built its armchair and zigzag photodetectors and studied linear and elliptical photogalvanic effects (PGEs) in these devices. It was found that produced photocurrents in the armchair and zigzag BC3 photodetectors mainly show cosine and sine relations on double times of linear or elliptical polarized angle, respectively. Moreover, since the decreasing of symmetry from D6H to C2v or Cs at the vacancy- and substitution-doping situations, the photocurrents in the armchair and zigzag BC3 photodetectors increased about 10–100 times, and the photocurrents even may be detected in experiments. Furthermore, the armchair and zigzag BC3 photodetectors are all polarization-sensitive for their high extinction ratios. In view of that the BC3 monolayer has been prepared, our work manifested great potential applications of the PGE-driven BC3 photodetectors in high performance and low energy-consumption optoelectronic and nanoelectronic devices.

Comparative first principles investigation on the structural, optoelectronic and vibrational properties of strain-engineered graphene-like AlC3, BC3 and C3N monolayers

Three cardinal two-dimensional semiconductors viz., AlC3, BC3 and C3N, closely resembling the graphene structure, are intriguing contenders for emerging optoelectronic and thermomechanical applications. Starting from a critical stability analysis, this density functional theory study delves into a quantitative assessment of structural, mechanical, electronic, optical, vibrational and thermodynamical properties of these monolayers as a function of biaxial strain (ε) in a sublinear regime (−2%⩽ε⩽4%) of elastic deformation. The structures with cohesive energies slightly smaller than graphene, manifest exceptional mechanical stiffness, flexibility and breaking stress. The mechanical parameters have been deployed to further cultivate acoustic attributes and thermal conductivity. The hexagonal structures with mixed ionic-covalent molecular bonds have indirect electronic band-gap and work-function acutely sensitive to ε . Dispersions of optical dielectric function, energy loss, refractive index, extinction coefficient, reflectivity, absorption coefficient and conductivity are deciphered in the UV–Vis–NIR regime against strain, where particular frequency bands featuring high polarization, dissipation, absorbance or reflectance are identified. Phonon band-structure and density of states testify dynamic stability in the ground state for all systems except the compressed ones. A comprehensive group theoretical analysis is performed to cultivate rotational; infrared and Raman-active modes, and the nature of molecular vibrations is delineated. The red-shifting of phonon bands and E2g/A1g Raman peaks with increasing ε , associates estimation of Grüneisen parameter. Finally, strain-induced alterations of thermodynamic quantities such as entropy, enthalpy, free energy, heat capacity and Debye temperature are studied, followed by a molecular dynamics-based stability assessment under canonical ensemble.

Retraction statement

This article refers to:RETRACTED ARTICLE: A sensitive N-nitroso-N-methylurea sensor based on graphene-like BC3 and NC3 layers

Nanosheets (CC-BC3-C3N) as an carrier for favipiravir drug: A density functional theory study

Two-dimensional nanostructures have recently been of great interest to researchers in drug delivery applications. Researchers developed two-dimensional NC3 and BC3 flake layers. The present work evaluates the drug delivery potential of pristine graphene and these two flakes through density functional theory (DFT) PBE/6-311+G (2d, p) mainly to measure their interactions with favipiravir drug. The results demonstrated that the aqueous phase had greater negative adsorption energy values. This indicated that these two flakes could undergo solubility improvement and be modified in drug interaction within the solvent phase. Moreover, the ultraviolent-visible (UV–vis) spectra results revealed a blue shift in the electronic spectral of the complexes to lower wavelengths. To further understand the binding characteristics of these systems with favipiravir (FP), the present study used atoms-in-molecules (AIM) analysis. The electrostatic properties of the bonding of BC3 flake and FP were determined. Finally, the graphene-like BC3 flake was found to be capable of serving as a promising carrier to deliver the FP drug.

Computational study of the effect of Fe-doping on the sensing characteristics of BC3 nano-sheet toward sulfur trioxide

Density functional theory (DFT) calculations were undertaken to investigate the effect of Fe-doping on the capability of a graphene-like BC3 nano-sheet (Fe@BC3NS) in detecting the gas SO3. The interaction of the pure BC3NS with SO3 was a physisorption, showing that it could not be used as a sensor. However, there was a considerable increase in the sensitivity and reactivity of the BC3NS after Fe was replaced with B. The adsorption energy of SO3 increased from 7.9 to 23.3 kcal/mol after doping Fe into the surface of the BC3NS. Moreover, there was a reduction in the energy gap of Fe@BC3NS (∼-38.9%) after SO3 was adsorbed, which increased the electrical conductivity to a great extent. Therefore, we found that Fe-doping increased the sensitivity of the BC3NS to SO3 with a short recovery time of 9.5 s at room temperature. Our theoretical results further supported the fact that metal@BC3 nano-structures have widespread practical applications.

Adsorption of metal atoms on two-dimensional BC3 and AlC3 nanosheets: Computational studies

The adsorption of metal atoms on two-dimensional (2D) nanomaterials shows promising applications in many aspects. In this work, the adsorption performance of 30 metal atoms on 2D graphene-like BC3 and AlC3 nanosheets have been systematically studied by density functional theory calculations. We determined the optimal adsorption strength and adsorption sites of metal atoms and analyzed the electronic properties and magnetic of “M@BC3” and “M@AlC3”. The results indicate that the existence of B and Al atoms can effectively improve the adsorption capability of metal atoms, meanwhile, the adsorption of metal atoms significantly changes the electronic and magnetic properties of 2D BC3 and AlC3 nanosheets.

BF3 adsorption on pure, Al-doped, and Sc-doped graphene-like BC3: a DFT study

BF3 adsorption on pure, Al-doped, and Sc-doped graphene-like BC3: a DFT study

A theoretical survey on the FCN detection by the intrinsic and Ti-doped boron carbide nanosheet

The adsorption of cyanogen fluoride (FCN) was explored onto intrinsic and Ti-doped graphene-like BC3 through density functional theory computations. An energy of 3.7 to 4.6 kcal/mol is released when FCN gests nearer to the BC3, which shows that the adsorption is weak. Also, there is no considerable change in the electronic properties of the nanosheet. Doping the BC3 with Ti improves its performance and makes it more reactive and sensitive to FCN. Based on the electronic analysis, it can be seen that the adsorption of FCN decreases the HOMO-LUMO energy gap of the Ti-doped BC3 from 2.18 to 1.37 eV. Therefore, electrical signals can be generated by the nanosheet doped with Ti as the FCN molecules come nearer. It shows that the nanosheet is a promising sensor. The recovery time for the Ti-doped BC3 was computed to be 6.2 s, representing a short recovery time.

Crack pathway analysis in graphene-like BC3 nanosheets: Towards a deeper understanding

Carbon based two-dimensional (2D) nanostructures have exceptional mechanical properties. Analysis of crack pathway in 2D graphenic materials allows for developing crack arrestors. Herein, we serve Molecular Dynamics (MD) to simulate the fracture behavior of 2D graphene-like boron-carbide (BC3) by manipulating the crack length (10, 20, 30, 40, and 50 Å) and the crack arrestor (circular and square). Young's modulus, the failure stress, failure strain, and fracture toughness of theoretically born BC3 nanosheets were then captured. The crack arrestors were studied in three different states (constant position, as well as 4 and 6 Å from crack tips). Three factors, i.e. the stress, crack length, and geometry of nanosheets determined crack pathway considering zigzag and armchair directions. Overall, circular arrestors more severely affected the fracture toughness, failure stress and failure strain with respect to square ones; while Young's modulus variation followed an inverse trend. Moreover, the highest Young's modulus was detected for cracks having length of 10 Å. Fracture toughness increased upon increasing the crack length. In conclusion, the crack arrestors were promising for tuning the mechanical properties of 2D nanosheets.

Graphene-like BC3 and NC3 flakes as promising drug delivery systems

In recent years, two-dimensional nanostructures have become some of the most interesting to be studied for application in the drug delivery. Novel two-dimensional layers, denoted by BC 3 and NC 3 flakes, have been previously synthesized. Motivated by these interesting nanomaterials, in the present study, we have investigated the pristine graphene as well as BC 3 and NC 3 flakes as versatile drug delivery systems. The main objective of the present work is to study the interaction of graphene, BC 3 , and NC 3 flakes with 5-fluorouracil (FU) anticancer drug using the density functional theory (DFT). We found that the more negative values of adsorption energies in the solvent phase reveal that the considered flakes can improve their solubility and modify their interaction with the drug in the aqueous phase. Also, our ultraviolet–visible analysis shows that the electronic spectra of the drug/sheet complexes show a blue shift toward lower wavelengths. To gain insight into the binding features of considered systems with FU drug, the Atoms in Molecules analysis was also performed. Our results determine the electrostatic features of the drug/BC 3 flake bonding. Therefore, ore calculations demonstrated that the graphene-like BC 3 flake could be used as potential carrier for the delivery of the 5-fluorouracil anticancer drug. Graphene-like BC3 flake as versatile drug delivery system. • The stability and electronic properties of graphene-like BC 3 and NC 3 flakes were studied. • The 5-fluorouracil adsorption on the surface of BC 3 is more favorable than the NC 3 . • Electronic spectra of drug/flake complexes exhibit a blue shift toward lower wavelengths. • BC 3 flake could be used as potential carrier for delivery of 5-fluorouracil in the nanomedicine domain.

RETRACTED ARTICLE: A sensitive N-nitroso-N-methylurea sensor based on graphene-like BC3 and NC3 layers

We, the Editor and Publisher of the journal Molecular Physics, have retracted the following article: Liao Yu, Liu Zongxin and Li Qiang (2020) A sensitive N-nitroso-N-methylurea sensor based on graphene-like BC3 and NC3 layers, Molecular Physics, 118:24. Article: e1790682 DOI: 10.1080/00268976.2020.1790682 The article was published without the agreement of Liao Yu and Liu Zongxin. Neither Liao Yu or Liu Zongxin were involved in writing this article and the article was published without their knowledge or consent. We have been informed in our decision-making by our policy on publishing ethics and integrity and the COPE guidelines on retractions. The retracted article will remain online to maintain the scholarly record, but it will be digitally watermarked on each page as ‘Retracted’.

First-principles calculations of stability of graphene-like BC3 monolayer and its high-performance potassium storage

With increasing demand for renewable energy, graphene-like BC3 monolayer as high performance electrode materials for lithium and sodium batteries are drawing more attention recently. However, its structural stability, potassium storage properties and strain effect on adsorption properties of alkali metal ions have not been reported yet. In this work, phonon spectra, AIMD simulations and elastic constants of graphene-like BC3 monolayer are investigated. Our results show that graphene-like BC3 monolayer possesses excellent structural stability and the maximum theoretical potassium storage capacity can reach up to 1653mAh/g with the corresponding open circuit voltages 0.66V. Due to potassium atom can be effectively adsorbed at the most energetically favorable h−CC site with obvious charge transfer, making adsorbed graphene-like BC3 monolayer change from semiconductor to metal which is really good for electrode utilization. Moreover, the migrations potassium atom on the graphene-like BC3 monolayer is rather fast with the diffusion barriers as low as 0.12eV, comparing lithium atom with a relatively large diffusion barrier of 0.46eV. Additionally, the tensile strains applied on the graphene-like BC3 monolayer have marginal effect on the adsorption and diffusion performances of lithium, sodium and potassium atoms.

Thermal conductivity and mechanical properties of graphene-like BC2, BC3 and B4C3

ABSTRACT Recently, carbon-based 2D nanomaterials have received significant attention because of their superior physical properties. In this investigation, the thermal conductivity (TC) and mechanical properties of graphene-like BC2, BC3 and B4C3 structures are systematically examined, using molecular dynamics (MD) simulations. For graphene-like BC2, BC3 and B4C3 structures, our MD results predict remarkably high thermal and mechanical properties. Especially, graphene-like BC3 structure indicates higher mechanical properties than graphene-like BC2 and B4C3 structures. Also, the mechanical properties of these graphene-like structures are investigated at four various temperatures from 200 to 900 K. Our results indicate that the mechanical properties of graphene-like structures gradually decrease as the temperature rises. In addition, the failure processes of graphene-like BC2, BC3 and B4C3 structures are examined at room temperature. According to the MD simulations, these graphene-like structures show brittle failure mechanism. In addition, graphene-like BC3 structure is more stretchable than other structures. Remarkably, non-equilibrium MD simulation results demonstrate ultra high TC values of graphene-like BC2, BC3 and B4C3 structures and so propose them for thermal management of polymeric materials or in nanoelectronics. Similar to the mechanical properties, graphene-like BC3 has higher TC value than others.

Superior sensitivity of metal functionalized boron carbide (BC3) monolayer towards carbonaceous pollutants

The sensitivity of light metal functionalized boron carbide (BC3) sheets towards selected carbonaceous gases like CO, CO2, and CH4 is investigated by using first principles density functional theory calculations. We find that functionalization with alkali (Li, Na, K) and alkaline earth metals (Be, Mg, Ca), is a useful strategy to improve the sensitivity of graphene-like BC3 towards the mentioned gases. A semiconductor-to-metal transformation of BC3 is observed upon the introduction of metal dopants. Gas molecules are adsorbed on the metallized BC3 through weak chemisorption, which is an ideal scenario for gas sensing under practical working conditions. We find that the adsorption energies (Eads) of CO molecule are found to be 1.71, 0.48, 0.34, 0.35, 0.96, and 0.84 eV on Be-, Li-, Na-, K-, Mg-, and Ca-doped BC3, respectively. Similarly, CO2 binds to Li-, Be-, Mg-, and Ca- doped BC3 with Eads of 0.54, 0.87, 0.61, and 0.43 eV, respectively. For CH4, an Eads value of 0.74 eV turns out to be the strongest in case of Be-BC3. Bader charge analysis divulges that the transfer of charges results in the adsorption mechanism of the gases to the metallized BC3. In addition to feasible Eads, change in the work function upon the adsorption of gas molecules further confirms good sensitivity of the metallized BC3 towards CO, CO2 and CH4. Based on our findings, we deduce that metal-doped BC3 is an excellent candidate for the efficient sensing of harmful pollutants.

Mechanical properties of graphene-like BC3; a molecular dynamics study

Experimentally fabricated two-dimensional materials have lately evoked significant attention in the nanodevice fabrication industry. In this manuscript, we study the mechanical response of crystalline boron-carbide with BC3 stoichiometry, which is a novel two-dimensional (2D) graphene-like material. Its excellent electrical, thermal and mechanical properties make it an exceptional candidate for a wide range of applications. However, different type of defects created during the production process or device assembly may deteriorate its remarkable mechanical properties. Hence, the purpose of this study is to investigate the mechanical properties of pristine and defective BC3 nanosheets through classical molecular dynamics (MD) simulations. Therefore, we study for the first time the influence of several crack lengths and notch diameters on the mechanical response at different temperatures under uniaxial tensile loading. Our results indicate that larger cracks and notches decrease the strength of 2D graphene-like BC3 nanosheets. Additionally, it was revealed that a temperature increase induces a weakening effect on the tensile strength of BC3 monolayer. Our MD results not only highlight the outstanding mechanical properties of graphene-like BC3, but also reveal its advantages regarding its thermo-mechanical properties, which are critical for the design of nanodevices.

Outstanding strength, optical characteristics and thermal conductivity of graphene-like BC3 and BC6N semiconductors

Carbon based two-dimensional (2D) materials with honeycomb lattices, like graphene, polyaniline carbon-nitride (C3N) and boron-carbide (BC3) exhibit exceptional physical properties. On this basis, we propose two novel graphene-like materials with BC6N stoichiometry. We conducted first-principles calculations to explore the stability, mechanical response, electronic, optical and thermal transport characteristics of graphene-like BC3 and BC6N monolayers. The absence of imaginary frequencies in the phonon dispersions confirm dynamical stability of BC3 and BC6N monolayers. Our first principles results reveal that BC3 and BC6N present high elastic moduli of 256 and 305 N/m, and tensile strengths of 29.0 and 33.4 N/m, with room temperature lattice thermal conductivities of 410 and 1710 W/m.K, respectively. Notably, the thermal conductivity of BC6N is one of the highest among all 2D materials. According to electronic structure calculations, monolayers of BC3 and BC6N are indirect and direct bandgap semiconductors, respectively. The optical analysis illustrate that the first absorption peaks along the in-plane polarization for single-layer BC3 and BC6N occur in the visible range of the electromagnetic spectrum. Our results reveal outstandingly high mechanical properties and thermal conductivity along with attractive electronic and optical features of BC3 and BC6N nanosheets and present them as promising candidates to design novel nanodevices.

Adsorptions of metal adatoms on graphene-like BC3 and their rich electronic properties: A first-principles study**Project supported by the National Natural Science Foundation of China (Grant Nos. 11774396 and 11704322) and Shandong Natural Science Funds for Doctoral Program, China (Grant No. ZR2017BA017).

Density functional calculations have been performed to investigate the adsorption of twenty two different kinds of metal adatoms on graphene-like BC3. In contrast to the graphene adsorbed with adatoms, the BC3 with adatoms shows many interesting properties. (1) The interaction between the metal adatoms and the BC3 sheet is remarkably strong. The Li, Na, K, and Ca possess the binding energies larger than the cohesive energies of their corresponding bulk metals. (2) The Li, Na, and K adatoms form approximately ideal ionic bonds with BC3, while the Be, Mg, and Ca adatoms form ionic bonds with BC3 with slight hybridization of covalent bonds. The Al, Ga, In, Sn, and all transition metal adatoms form covalent bonds with BC3. (3) For all the structures studied, there exhibit metal, half-metal, semiconducting, and spin-semiconducting behaviors. Especially, the BC3 with Co adatom shows a quantum anomalous Hall (QAH) phase with a Chern number of −1 based on local density approximation calculations. (4) For Li, Na, K, Ca, Ga, In, Sn, Ti, V, Cr, Ni, Pd, and Pt, there exists a trend that the adatom species with lower ionization potential have lower work function. Our results indicate the potential applications of functionalization of BC3 with metal adatoms.

Robust quantum spin Hall state and quantum anomalous Hall state in graphenelike BC3 with adatoms

Two-dimensional (2D) topological insulators (TIs) and Chern insulators (CIs) promise quantum spin Hall (QSH) and quantum anomalous Hall (QAH) states without dissipation. By combining first-principles calculations with Wannier functions-based tight-binding (TB) modeling, we demonstrate that the graphenelike BC3, which was fabricated early in experiment, can become 2D TIs and CIs through suitable decoration of adatoms. For the thallium (Tl) decorated BC3 systems, three low-energy structures with the same stoichiometry of BC3Tl, whose stabilities are verified by the ab initio evolutionary algorithm, are found to be robust 2D TIs with the largest topologically nontrivial band gap of about 224 meV. For the transition metal atoms adsorbed BC3, three (2 × 2) BC3 systems with one adatom of technetium (Tc), rhenium (Re), or ruthenium (Ru) are found to be good CIs with the ferromagnetic moments of 1 to 2 μB, nontrivial gaps of 38–50 meV, and nonzero Chern numbers of −1 to 1. These properties indicate that the systems of graphenelike BC3 with adatoms are good platforms for the study of QSH and QAH effects.

Non-metal atom anchored BC3 sheet: a promising low-cost and high-activity catalyst for CO oxidation

Graphene-like BC3 monolayer as a new semiconducting nanomaterial has many unique properties.

Insights into the electronic properties and reactivity of graphene-like BC3 supported metal catalysts

Graphene-like BC3 monolayer is a new two-dimensional nanomaterial with many unique properties, but is still largely unknown.