Boron Phosphide Monolayer Research Articles

The effects of bias voltage and magnetic field on optical properties of boron phosphide monolayer

The effects of bias voltage and magnetic field on optical properties of boron phosphide monolayer

Selective adhesion of nitrogen-containing toxic gasses on hexagonal boron phosphide monolayer: a computational study.

Various toxic gasses are being released into the environment with the increasing industrialization. However, detecting these gasses at low concentrations has become one of the main challenges in environmental monitoring and protection. Thus, developing sensors with high performance to detect toxic gasses is of utmost significance. For this purpose, researchers have introduced 2D materials thanks to their unique electronic qualities and large specific surface area. Within this piece of research, a hexagonal boron phosphide monolayer (h-BPML) is employed as the substrate material. The adhesion behavior of ambient nitrogen-containing toxic gasses, i.e., N2O, NH3, NO2, and NO, onto the h-BPML is investigated through DFT computations. The adhesion energy values for gasses NO and NO2 were calculated to be - 0.509 and - 0.694 eV on the h-BPML, respectively. Meanwhile, the absorbed energy values for gasses NH3 and N2O were found to be - 0.326 and - 0.119 eV, respectively. The recovery time, DOS, workfunction, and Bader charges were computed based on four optimal adhesion structures. After the absorption of NO on the h-BPML, the value of workfunction of a monolayer decreased from 1.54 to 0.47 eV. This amount of decrease was the greatest among the other gasses absorbed. By comparing the investigated parameters, it can be concluded that the h-BPML has a greater tendency to interact with NO gas compared to other gasses, and it can be proposed as a sensor for NO gas. Within this piece of research, the sensitivity of the h-BPML to four nitrogenous toxic gasses, namely, N2O, NH3, NO2, and NO, was investigated using the DFT with HSE06 hybrid functional by using GAMESS software. For this purpose, we computed the DOS, workfunction, and the Bader charges for the four adhesion systems with most stability.

Strain-Driven High Thermal Conductivity in Hexagonal Boron Phosphide Monolayer.

Two-dimensional graphenelike material, hexagonal boron phosphide (h-BP), is a promising candidate for electronic and optoelectronic devices because of its suitable band gap and high carrier mobility. Especially from the ultrahigh lattice thermal conductivity (κl), it exhibits great potential to solve the challenges of future thermal management applications. Here, the excellent lattice thermal transport properties of the h-BP monolayer are systematically analyzed at the atomic level based on the first-principles method. The results show that the ultrahigh κl value of the h-BP monolayer is attributed to its high phonon group velocity and long phonon lifetime and the strong phonon hydrodynamic effect. We further explore the influence of the tensile strain on the thermal transport properties of the h-BP monolayer. As the strain increases from 0 to 8%, the κl value shows a trend of first increasing and then decreasing due to the coeffect of strain-driven changes for phonon harmonicity and anharmonicity. Under a strain of 6%, the κl value of the h-BP monolayer is as high as 795 W/mK at 300 K, which is about 2.22 times larger than that of 357 W/mK without strain. Such a significant increase in the κl value is mainly due to the increased phonon group velocity and decreased Grüneisen parameter caused by strain. This work is helpful to understand the critical role of tensile strain in lattice thermal transport of two-dimensional graphenelike materials. It is conducive to promoting the thermal management application of the h-BP monolayer.

Functionalization of boron phosphide monolayers for spintronic applications by doping with alkali and alkaline earth metals

In this work, new d 0 magnetic materials are developed by doping boron phosphide (BP) monolayers with alkali (Li, Na, and K) and alkaline earth (Be, Mg, and Ca) metals. First-principles calculations confirm the good dynamical and thermal stability of the pristine monolayer. This two-dimensional model is intrinsically a non-magnetic semiconductor with a band gap of 0.90/1.36 eV, as calculated by the PBE/HSE06 functional. B-P chemical bonds are predominantly covalent, generated by electronic hybridization with a small portion of the ionic character formed by the charge transfer from the B atom to the P atom. Doping with Li, Be, and Mg on the B sublattice preserves the non-magnetic nature, causing either a considerable reduction of the band gap or metallization. Meanwhile, the monolayer is significantly magnetized with a total magnetic moment between 0.94 and 3.86 µ B in the remaining cases. Herein, magnetic properties are primarily produced by p orbitals of impurities and their neighboring host atoms, whereas Ca-3d orbitals also contribute to the magnetism of Ca-doped systems. Moreover, the doping process enables the emergence of either half-metallic or magnetic semiconductors in the BP monolayer to get prospective d 0 magnetic materials and generate spin current. The results presented herein demonstrate the effectiveness of doping with alkali and alkaline earth metals to obtain magnetized BP monolayers with feature-rich electronic properties, such that the doped systems can be recommended for applications in nano spintronic devices.

Transition Metal-Doped Boron Phosphide Monolayer in Lithium–Sulfur Batteries with Anchoring Ability and Catalytic Performance: A First-Principles Study

Transition Metal-Doped Boron Phosphide Monolayer in Lithium–Sulfur Batteries with Anchoring Ability and Catalytic Performance: A First-Principles Study

Strain Dependent Electronic Properties of Hexagonal Monolayer Boron Phosphide with GPAW using GLLB-SC and PBE

The electronic properties of the hexagonal Boron Phosphide (h-BP) monolayer have been investigated by first-principles calculations. The electronic band structure of the h-BP monolayer has been calculated using GPAW with PBE and GLLB-SC exchange correlations (XCs). The energy band gaps of the h-BP monolayer are found to be 0.89 eV and 1.05 eV for PBE and GLLB-SC, respectively. It is shown that GLLB-SC in calculations as XC ensures a more accurate energy band gap than the PBE. As well as the electronic calculations of the unstrained h-BP monolayer, the strain calculations are performed between +5 and -5 %. The strain in the h-BP monolayer changed the energy band gap between 0.78 eV and 1.24 eV for GLLB-SC and between 0.66 eV and 1 eV for PBE. In this applied strain range the studied structure shows the direct band gap semiconductor behavior.

Electro-optical properties of strained monolayer boron phosphide

In this paper, we use tight-binding approximation and linear response theory to study the electronic and optical properties of strained monolayer boron-phosphide (h-BP). Compared with the previous DFT study and adding on-site energy variation to the Hamiltonian, we propose a theoretical approach to investigate the strain effects on the electronic and optical properties of the h-BP. Applying tensile strain increases the gap while compressive strain reduces it as the maximum and minimum of the gap are 1.45 eV and 1.14 eV respectively and are related to the biaxial strain. Also, we investigate the optical conductivity and electron energy loss spectrum (EELS) of the pristine and strained h-BP. The absorption peak of the Resigma_{xx,yy} appears in energy about 4 eV but applying strain shifts the peak’s energy. Optical properties of pristine h-BP are isotopic and biaxial strain preserves this isotropy, but uniaxial strain exerts anisotropic behavior in the system.

Ballistic transport in 5.1 nm monolayer boron phosphide transistors for high-performance applications

Boron Phosphide is reported to be a semiconductor material with anisotropy, tunable bandgap, and high carrier mobility. We study the performance of 5.1 nm metal–oxide–semiconductor field-effect transistors (MOSFETs) based on boron phosphide using quantum transport simulation. The calculated results show that the on-state current can fulfill the requirements of the International Semiconductor Technology Roadmap (ITRS) for high-performance (HP) devices at the optimal doping concentration, but the gate control capability is not ideal. Furthermore, it is found that the gate control capability and on-state current can be significantly improved with the length being 1 nm by using the underlap (UL) structure. We also study the performance of boron phosphide MOSFET with different gate lengths (5–8 nm), and the results suggest that the shorter the gate length, the worse the gate control capability. Interestingly, the p-type boron phosphide MOSFET always outperforms the n-type MOSFET. This work will provide a new reference for the development of two-dimensional (2D) semiconductor devices.

Electrocatalytic study of the hydrogen evolution reaction on MoS2/BP and MoSSe/BP in acidic media.

Molecular hydrogen (H2) production by the electrochemical hydrogen evolution reaction (HER) is being actively explored for non-precious metal-based electrocatalysts that are earth-abundant and low cost like MoS2. Although it is acid-stable, its applicability is limited by catalytically inactive basal planes, poor electrical transport and inefficient charge transfer at the interface. Therefore, the present work examines its bilayer van der Waals heterostructure (vdW HTS). The second constituent monolayer boron phosphide (BP) is advantageous as an electrode material owing to its chemical stability in both oxygen and water environments. Here, we have performed first-principles based calculations under the framework of density functional theory (DFT) for the HER in an electrochemical double layer model with the BP monolayer, MoS2/BP and MoSSe/BP vdW HTSs. The climbing image nudged elastic band method (CI-NEB) has been employed to determine the minimum energy pathways for Tafel and Heyrovsky reactions. The calculations reveal that the Tafel reaction shows no reaction barrier. Thereafter, for the Heyrovsky reaction, we obtained a low reaction barrier in the vdW HTSs as compared to that in the BP monolayer. Subsequently, we have observed no significant difference in the reaction profile of MoS2/BP and MoSSe/BP vdW HTSs in the case of 2 × 2 supercell configuration. However, in the case of 3 × 3 and 4 × 4 configurations, MoSSe/BP shows a feasible Heyrovsky reaction with no reaction barrier. The coverages with 1/4H+ concentration (conc.) deduced high coverage with low conc. and low coverage with high conc. to be apt for the HER via the Heyrovsky reaction path. Finally, on observing the activation barrier of the Heyrovsky pathway along with that of second H adsorption at the surface, the Heyrovsky path is expected to be favoured.

Computational screening of single-atom catalysts for direct electrochemical NH3 synthesis from NO on defective boron phosphide monolayer

Selective electrocatalytic reduction of NO to ammonia provides a promising way to remove pollutant NO and realize green ammonia synthesis under ambient conditions. The key to promote the practical application of NO reduction reaction (NORR) is to develop economical and efficient electrocatalysts to replace Pt-based catalysts. In this work, we designed a series of transition metal (TM) single-atom catalysts (SACs) supported on BP monolayer with a B vacancy (TM@BP, TM = Ti ∼ Zn, Zr ∼ Ag, and Hf ∼ Au), and systematically investigated their performance of electrocatalytic NORR by means of density functional theory (DFT). Taking the changes of free energy of the first (NO → NOH/NO → NHO) and last (OH → H2O/NH2 → NH3) hydrogenation steps of NORR as the screening criteria, seven TM@BP (TM = Ti, V, Cu, Rh, Ag, Ir, and Au) were selected from eighteen candidates. All possible reaction pathways of NORR to produce NH3 and byproducts (N2O, N2 and H2) were considered. Our calculated results show that Ti@BP, V@BP, Cu@BP, and Au@BP not only exhibit similar catalytic activity to Pt-based catalysts, but also have excellent NORR selectivity toward NH3, so they are predicted to be the most promising catalysts. This work provides useful guidance for the design and exploration of efficient NORR electrocatalysts.

Hydrogenated Boron Phosphide THz-Metamaterial-Based Biosensor for Diagnosing COVID-19: A DFT Coupled FEM Study.

Recent reports focus on the hydrogenation engineering of monolayer boron phosphide and simultaneously explore its promising applications in nanoelectronics. Coupling density functional theory and finite element method, we investigate the bowtie triangle ring microstructure composed of boron phosphide with hydrogenation based on structural and performance analysis. We determine the carrier mobility of hydrogenated boron phosphide, reveal the effect of structural and material parameters on resonance frequencies, and discuss the variation of the electric field at the two tips. The results suggest that the mobilities of electrons for hydrogenated BP monolayer in the armchair and zigzag directions are 0.51 and 94.4 cm2·V-1·s-1, whereas for holes, the values are 136.8 and 175.15 cm2·V-1·s-1. Meanwhile, the transmission spectra of the bowtie triangle ring microstructure can be controlled by adjusting the length of the bowtie triangle ring microstructure and carrier density of hydrogenated BP. With the increasing length, the transmission spectrum has a red-shift and the electric field at the tips of equilateral triangle rings is significantly weakened. Furthermore, the theoretical sensitivity of the BTR structure reaches 100 GHz/RIU, which is sufficient to determine healthy and COVID-19-infected individuals. Our findings may open up new avenues for promising applications in the rapid diagnosis of COVID-19.

High-Throughput Screening of Single-Atom Catalysts for Direct Electrochemical Nh3 Synthesis from No on Defective Boron Phosphide Monolayer

High-Throughput Screening of Single-Atom Catalysts for Direct Electrochemical Nh3 Synthesis from No on Defective Boron Phosphide Monolayer

A DFT Study on the Potential Application of Graphene-Like Pure and Doped Boron Phosphide Monolayer in Li- and Na-Ion Batteries

A DFT Study on the Potential Application of Graphene-Like Pure and Doped Boron Phosphide Monolayer in Li- and Na-Ion Batteries

Self-energy corrected band-gap tuning induced by strain in the hexagonal boron phosphide monolayer

We performed a first-principles study of the electronic behavior of a 2D hexagonal boron phosphide monolayer (2D-h-BP). The system was deformed isotropically by applying a simultaneous tensile strain along the a and b crystal axes. We analyzed the band-gap evolution as function of the deformation percentage, ranging from 1% to 8%. Results show that the system behaves as a direct band-gap semiconductor, with the valence band maximum and conduction band minimum located at the K point (1/3, 1/3, 0) of the Brillouin zone. This behavior is unchanged despite the strain application. The band gap underestimation, as computed within the standard DFT, was corrected by applying the G0W0 approach. Trends in the band-gap behavior are the same within both approaches: for low deformation percentages, the band-gap grows linearly with a small slope, and at higher values, it grows very slow with a tendency to achieve saturation. Therefore, the band-gap is less sensitive to tensile strain for deformations near 8%. The origin of this band gap behavior is explained in terms of the projected density of states and charge densities, and it can be attributed to Coulomb interactions, and charge redistributions due to the applied tensile strain. To study the carrier mobility, we computed the electron and hole effective masses, finding high mobility for both carriers. Finally, the stability analysis of each strained system includes the calculation of phonon spectra, to assure the dynamical stability, the computation of elastic constants to evaluate the mechanical stability, and cohesive energies for exploring the thermodynamical stability. Results indicate that the boron phosphide monolayer is stable under the calculated tensile strains.

Ab initio study on electronic structure and magnetic properties of AlN and BP monolayers with Ti doping

The spintronic properties of Aluminum Nitride (AlN) and Boron Phosphide (BP) monolayers with Titanium (Ti) doping have been studied by using first principles calculation. The Ti-doped AlN monolayer will produce the magnetic moment of 1 μ B , which is mainly contributed by d orbital of the impurity. Although Ti P (Phosphorus was replaced by Ti) can lead to semi-metallic properties in BP monolayer, Ti B (Boron was replaced by Ti) has a lower formation energy. The magnetic moment produced by Ti B is 1 μ B , which is also mainly contributed by the Ti- d orbital. The strain studies show that the band gap of AlN monolayer will decrease with the increase of strain, while the pristine BP monolayer increases. Ti B will make the band gap of BP increase first and then decrease when it is 10%. Studies on magnetic coupling indicate that ferromagnetic and antiferromagnetic coupling oscillations will occur at different Ti-Ti distances in the AlN monolayer. However, Ti B -Ti B are always coupled antiferromagnetically at each distance in the BP monolayer. Further study shows that the Néel temperature of the BP system with Ti B may be higher than room temperature. • Applying strain can regulate the band gap of AlN and BP materials regularly. • The magnetic coupling between Ti atoms in AlN monolayer will oscillate regularly. • The results show that Ti P will make BP monolayer produce semi-metallic properties. • The study found that Ti B -doped BP has a Néel temperature above room temperature.

Hydrogenated boron phosphide with the excellent tunability of electronic properties and Current-Voltage responses

Combining the first principles calculations and the non-equilibrium Green’s function formalisms, we decipher the structural, electronic, and transport properties of boron phosphide (BP) with hydrogenation. Hydrogenated BP monolayer is an indirect semiconductor with a wide-bandgap of 3.76 eV that is favorable in power devices. We find that the electronic properties are dependent of the stacking orders and the binding strength of the AA-, AB-, and AE-stacked patterns are strongest in the investigated configurations. Under the external E-field, the bandgaps of hydrogenated BP bilayer show a quasi-parabolic function and a feature of the semiconductor-metallic transition. Besides, when we apply a tensile strain on hydrogenated BP bilayer, its bandgap linearly decreases with the increasing of the strain strength along the zigzag and armchair directions. The strain energies further confirm that hydrogenated BP has an excellent characteristic of elastic deformation, being independent of the stacking orders and strain orientation. The transport calculations exhibit various responses to the different two-probe configurations, which indicates that hydrogenated BP possesses the feature of transmission anisotropy. Owing to the nontrivial tunability and transport feature, the hydrogenated BP materials may have tremendous prospects to be applied in micro-/nano-devices with high consumption.

Band Alignment in Monolayer Boron Phosphide with Janus MoSSe Heterobilayers under Strain and Electric Field

Recent studies have revealed that Janus structures and heterobilayers made from them might have properties superior to those of two-dimensional (2D) materials. We construct 2D monolayer boron phosphide (MBP)/$\mathrm{Mo}\mathrm{S}\mathrm{Se}$ and $\mathrm{Mo}\mathrm{S}\mathrm{Se}$/MBP heterobilayers and describe comprehensively their optoelectronic properties in the presence of biaxial in-plane and uniaxial out-of-plane strain and the effects of electric fields using first-principles methods. The electronic bands of both MBP/$\mathrm{Mo}\mathrm{S}\mathrm{Se}$ and $\mathrm{Mo}\mathrm{S}\mathrm{Se}$/MBP heterobilayers display a peculiarity in the direct gap, with different band-gap values in the pristine forms. Remarkably, it is shown that different varieties of band alignments are induced for different orders of the van der Waals (vdW) heterobilayers. Electric fields and in-plane and out-of-plane strain give rise to important changes in the electronic and optical properties. The band alignments can transform from type I to type II under the influence of an electric field and strain. The main absorption peaks of pristine forms of both heterobilayers have in the visible region (approximately 2.67 eV), while in the presence of biaxial strain are redshifted. Since the absorption peaks of the pristine forms of the heterobilayers are in the visible region, the heterobilayers recommended here can be used in photovoltaic applications, and the presence of effects of external electric fields and strain promises functional optoelectronic devices.

Defects and Strain Engineering of Structural, Elastic, and Electronic Properties of Boron-Phosphide Monolayer: A Hybrid Density Functional Theory Study.

Defects and in-plane strain have significant effects on the electronic properties of two-dimensional nanostructures. However, due to the influence of substrate and environmental conditions, defects and strain are inevitable during the growth or processing. In this study, hybrid density functional theory was employed to systematically investigate the electronic properties of boron-phosphide monolayers tuned by the in-plane biaxial strain and defects. Four types of defects were considered: B-vacancy (B_v), P-vacancy (P_v), double vacancy (D_v), and Stone–Wales (S-W). Charge density difference and Bader charge analysis were performed to characterize the structural properties of defective monolayers. All of these defects could result in the boron-phosphide monolayer being much softer with anisotropic in-plane Young’s modulus, which is different from the isotropic modulus of the pure layer. The calculated electronic structures show that the P_v, D_v, and S-W defective monolayers are indirect band gap semiconductors, while the B_v defective system is metallic, which is different from the direct band gap of the pure boron-phosphide monolayer. In addition, the in-plane biaxial strain can monotonically tune the band gap of the boron-phosphide monolayer. The band gap increases with the increasing tension strain, while it decreases as the compression strain increases. Our results suggest that the defects and in-plane strain are effective for tuning the electronic properties of the boron-phosphide monolayer, which could motivate further studies to exploit the promising application in electronics and optoelectronics based on the boron-phosphide monolayer.

Thermoelectric transports in pristine and functionalized boron phosphide monolayers

Recently, a new monolayer Group III–V material, two-dimensional boron phosphide (BP), has shown great potential for energy storage and energy conversion applications. We study the thermoelectric properties of BP monolayer as well as the effect of functionalization by first-principles calculation and Boltzmann transport theory. Combined with a moderate bandgap of 0.90 eV and ultra-high carrier mobility, a large ZT value of 0.255 at 300 K is predicted for two-dimensional BP. While the drastically reduced thermal conductivity in hydrogenated and fluorinated BP is favored for thermoelectric conversion, the decreased carrier mobility has limited the improvement of thermoelectric figure of merit.

Structural, elastic, and electronic properties of chemically functionalized boron phosphide monolayer.

Surface functionalization is one of the useful techniques for modulating the mechanical and electronic properties of two-dimensional systems. In the present study, we investigate the structural, elastic, and electronic properties of hexagonal boron phosphide monolayer functionalized by Br and Cl atoms using first-principles predictions. Once surface-functionalized with Br/Cl atoms, the planar structure of BP monolayer is transformed to the low-buckled lattice with the bucking constant of about 0.6 Å for all four configurations of functionalized boron phosphide, i.e., Cl–BP–Cl, Cl–BP–Br, Br–BP–Cl, and Br–BP–Br. The stability of functionalized BP monolayers is confirmed via their phonon spectra analysis and ab initio molecular dynamics simulations. Our calculations indicate that the functionalized BP monolayers possess a fully isotropic elastic characteristic with the perfect circular shape of the angle-dependent Young's modulus and Poisson's ratio due to the hexagonal symmetry. The Cl–BP–Cl is the most stiff with the Young's modulus C2D = 43.234 N m−1. All four configurations of the functionalized boron phosphide are direct semiconductors with a larger band gap than that of a pure BP monolayer. The outstanding stability, isotropic elastic properties, and moderate band gap make functionalized boron phosphide a very intriguing candidate for next-generation nanoelectromechanical devices.