Band inversion and switchable magnetic properties of two-dimensional RuClF/WSe2 van der Waals heterostructures.

Two-dimensional (2D) van der Waals (vdW) heterostructures have potential applications in new low-dimensional spintronic devices owing to their unique electronic properties and magnetic anisotropy energies (MAEs). The electronic structures and magnetic properties of RuClF/WSe2 heterostructure are calculated using first-principles calculations. The most stable RuClF/WSe2 heterostructure is selected for property analysis. RuClF/WSe2 heterostructure has half-metallicity. Considering spin-orbit coupling (SOC), band inversion is present in the RuClF/WSe2 heterostructure, which is also demonstrated by the weight of the energy contributions. The local density of states (LDOS) of the edge states can provide strong evidence that the RuClF/WSe2 heterostructure has topological properties. The MAE of RuClF/WSe2 heterostructure is in-plane magnetic anisotropy (IMA), which mainly originates from the contribution of matrix element difference in Ru (dxy, dx2-y2) orbitals. The electronic properties and MAE of RuClF/WSe2 heterostructure can be regulated by biaxial strains and electric fields. The band inversion phenomenon is enhanced at electric fields in the opposite direction, which is also modified at different biaxial strains. However, the band inversion phenomenon disappears at the biaxial strains of 6% and an electric field of 0.5 V Å-1. The MAE of RuClF/WSe2 heterostructure is transformed from IMA into perpendicular magnetic anisotropy (PMA) at certain compressive strains and positively directed electric fields. The above results indicate that the RuClF/WSe2 heterostructure has potential applications in spintronic devices.

Dirac semimetallic Janus Ni-trihalide monolayer with strain-tunable magnetic anisotropy and electronic properties.

Two-dimensional (2D) ferromagnetic (FM) semiconductors have been paid much attention due to the potential applications in spintronics. Here, the electronic and magnetic properties of 2D Janus Ni-trihalide monolayer Ni2X3Y3 (X, Y = I, Br, Cl; X ≠ Y) are investigated by first-principle calculations. The properties of Ni2X3Y3 (X, Y = I, Br, Cl; X ≠ Y) monolayers are compared by selecting the NiCl3 monolayer as the reference material. Ni2X3Y3 monolayers have two distinct magnetic ground states of ferromagnetic (FM) and antiferromagnetic (AFM). In the Ni2X3Y3 monolayer, two different orbital splits were observed, one semiconductor state and the other semimetal state. The semimetal state of Ni2X3Y3 can be tuned to semiconductor or metallic state when biaxial strain is applied. The magnetic anisotropy energy (MAE) of the Ni2X3Y3 monolayer can display variations compared to that of the NiCl3 monolayer, with the direction of easy magnetization being influenced by the specific halogen elements present. The easy magnetization direction of Ni2X3Y3 can also be changed by applying biaxial strain. The Tc of Ni2X3Y3 is predicted to be about 100 K according to the calculation of the EAFM-EFM model. The design of the Janus Ni2X3Y3 structure has expanded the range of 2D magnetic materials, a significant contribution has been made to the advancement of spintronics and its applications.

Spin-splitting and switchable half-metallicity in a van der Waals multiferroic CuBiP2Se6/GdClBr heterojunction.

Multiferroic van der Waals (vdW) heterojunctions have a strong and nonvolatile magnetoelectric coupling effect, which is of great significance in spintronic devices. The electronic structure and magnetic properties of a GdClBr/CuBiP2Se6 vdW multiferroic heterojunction have been calculated using first-principles methods. Due to the spin-up charge transfer and Zeeman field, the ferroelectric CuBiP2Se6 exhibits spin splitting at the gamma point. It is found that the electronic structure and magnetic properties of the GdClBr/CuBiP2Se6 vdW multiferroic heterojunction have been significantly modulated by the electric polarization of CuBiP2Se6. During the reversal of the ferroelectric polarization of CuBiP2Se6, the ferromagnetic GdClBr monolayer transforms from a semiconductor to a half-metal. Meanwhile, in both upward and downward ferroelectric polarization, the GdClBr/CuBiP2Se6 heterojunction exhibits perpendicular magnetic anisotropy with a Curie temperature of 239 K. As the strain changes from -6% to 6%, the band structure of GdClBr shifts upward, and the band structure of CuBiP2Se6 shifts downward. Compressive strain can increase the Curie temperature of the GdClBr/CuBiP2Se6 heterojunction. The magnetic anisotropy of heterojunctions highly depends on biaxial strain, where the perpendicular (in-plane) magnetic anisotropy increases with the increased compressive (tensile) strain. The vdW multiferroic GdClBr/CuBiP2Se6 heterojunction has potential applications in spintronic devices.

Two dimensional Janus RuXY (X, Y = Br, Cl, F, I, X ≠ Y) monolayers: ferromagnetic semiconductors with spontaneous valley polarization and tunable magnetic anisotropy.

Two-dimensional (2D) ferromagnetic (FM) materials with valley polarization are highly desirable for use in valleytronic devices. The 2D Janus materials have fascinating physical properties due to their asymmetrical structures. In this work, the electronic structure and magnetic properties of Janus RuXY (X, Y = Br, Cl, F, I, X ≠ Y) monolayers are systematically studied using first-principles calculations. RuBrCl, RuBrF, and RuClF monolayers are all FM semiconductors. The valley polarization is present in the band structure and this is determined by the spin orbit coupling (SOC). The valley splitting energy of the RuClF monolayer is as large as 204 meV, with a perpendicular magnetic anisotropy (PMA) energy of 1.918 mJ m-2 and a Curie temperature of 316 K. Therefore, spontaneous valley polarization at room temperature will be seen in the RuClF monolayer. The Curie temperature of the RuBrF monolayer is higher than that of the RuClF, but the magnetic anisotropy energy (MAE) is in-plane magnetic anisotropy (IMA). The valley splitting energy of the RuBrCl monolayer is higher and the PMA energy is lower than that of the RuClF monolayer. The Curie temperature was only 197 K. The valley polarization was modulated in the RuXY monolayers at different biaxial strains, during which the semiconductor properties are still maintained. The PMA of the RuClF and RuBrCl monolayers is enhanced by the biaxial compressive strains, which are mainly attributed to the variation of the (dyz, d2z) orbital matrix elements of the Ru atoms. The MAE of the RuBrF monolayer is tuned from IMA into PMA at a biaxial strain of -6%. These results show an example of a 2D Janus ferrovalley material.

Core-Shell Three-Dimensional Perovskite Nanocrystals with Chiral-Induced Spin Selectivity for Room-Temperature Spin Light-Emitting Diodes.

We developed type-II core-shell nanocrystals (NCs) with a chiral low-dimensional perovskite shell and an achiral 3D MAPbBr3 core. The core-shell NCs exhibit spin-polarized luminescence at the first excitation band of the achiral core, which is due to the chiral-induced spin selectivity (CISS) effect-governed spin-dependent shell-to-core electron transportation and the subsequent electron-hole recombination in the core. The preferred spin state of the transferred electrons is determined by the handness of the chiral shell. For the core-shell NCs film, a photoluminescence quantum yield (PLQY) of 54% and a circularly polarized luminescence (CPL) with a maximum |glum| of 4.0 × 10-3 are obtained at room temperature. Finally, we achieved a spin-polarized light-emitting diode (spin-LED), affording a circularly polarized electroluminescence (CP-EL) with a |gCP-EL|of 6.0 × 10-3 under ambient conditions.

Large perpendicular magnetic anisotropy of transition metal dimers driven by polarization switching of a two-dimensional ferroelectric In2Se3 substrate.

Large perpendicular magnetic anisotropy (MA) is highly desirable for realizing atomic-scale magnetic data storage which represents the ultimate limit of the density of magnetic recording. In this work, we study the MA of transition metal dimers Co-Os, Co-Co and Os-Os adsorbed on two-dimensional ferroelectric In2Se3 (In2Se3-CoOs, In2Se3-OsCo, In2Se3-CoCo and In2Se3-OsOs) using first-principles calculations. We find that the Co-Os dimer in In2Se3-CoOs has a total magnetic anisotropy energy (MAE) of ∼40 meV. The MAE arising from the Os atom in In2Se3-CoOs is up to ∼60 meV. Such large MAE is attributed to the high spin-orbit coupling constant and the onefold coordination of the Os atom. In addition, perpendicular MA can be enhanced in In2Se3-CoOs and induced in In2Se3-OsCo, In2Se3-CoCo and In2Se3-OsOs by the ferroelectric polarization reversal of In2Se3. We demonstrate that the enlargement of exchange splitting of dxy/dx2-y2 and dxz/dyz orbitals for Os atoms in In2Se3-OsOs, Co atom in In2Se3-CoOs and Os and Co atoms in In2Se3-OsCo is responsible for the increase of MAE; while, for the upper Co atom in In2Se3-CoCo and the Os atom in In2Se3-CoOs, the energy rise of the dz2 orbital owing to the change of the crystal field effect by the reversal of ferroelectric polarization results in the increase of MAE.

Orientational Alignment of Oxygen Vacancies: Electric-Field-Inducing Conductive Channels in TiO2 Film to Boost Photocatalytic Conversion of CO2 into CO.

Oxide semiconductors are widely used in the photocatalytic fields, and introducing oxygen vacancies is an effective strategy to improve their photocatalytic efficiency. However, oxygen vacancies in the bulk often act as the recombination centers of electron-hole pairs, which accelerates the recombination of electron-hole pairs. In this paper, we propose a strategy of electric field treatment and apply it to a TiO2 film with oxygen vacancies to promote the photocatalytic efficiency. After treatment by an electric field, the conductive channels consisting of oxygen vacancies are formed in the TiO2 film, which greatly decreases the resistance by almost 6 × 103 times. The yield of CO can reach up to 1.729 mmol gcat-1 h-1, which is one of the best performances among the reported TiO2-based catalysts. This work provides an effective and feasible way for enhancing photocatalytic activity through an electric field, and this method is promising for wide use in the field of catalysis.

Induced half-metallic characteristics and enhanced magnetic anisotropy in the two-dimensional Janus V2I3Br3 monolayer by graphyne adsorption.

The recent emergence of two-dimensional (2D) Janus materials has opened a new avenue for spintronic and optoelectronic applications. However, 2D magnetic Janus materials and Janus monolayer-based magnetic heterostructures are yet to be fully studied. Herein, the stability and electronic structure of 2D Janus V2I3Br3 and V2I3Cl3 monolayers, and the electronic and magnetic properties of 2D graphyne/Janus V2I3Br3 (γ-GY/V2I3Br3) heterostructures are calculated based on the density functional theory. Janus V2I3Br3 and V2I3Cl3 monolayers are ferromagnetic semiconductors with good stability and direct band gap. By combing the graphyne layer, the Janus V2I3Br3 monolayer shows half-metallic characteristics. The electrical conductivity of the Janus V2I3Br3 monolayer in γ-GY/V2I3Br3 heterostructures is further improved, which is very favorable for the applications of the γ-GY/V2I3Br3 heterostructure in battery anodes. Moreover, the Janus V2I3Br3 monolayer possesses a smaller perpendicular magnetic anisotropy (PMA), and the PMA can be effectively enhanced by combing γ-GY. Herein, the enhanced PMA was discovered to depend on the stacking patterns of γ-GY and V2I3Br3 monolayers. Biaxial strains can further affect the PMA of the γ-GY/V2I3Br3 heterostructure. Meanwhile, at a compressive strain, the Janus V2I3Br3 monolayer in the γ-GY/V2I3Br3 heterostructure realizes the transition from the magnetic half-metallic to the magnetic metal state. These results can enrich the applications and designs of γ-GY/V2I3Br3 magnetic heterostructures in spintronic devices and energy fields.

Electric field induced reversal of spin polarization, magnetic anisotropy and tailored Dzyaloshinskii-Moriya interaction in underoxidized SrRuO3/SrTiO3 heterostructures.

Electric field tailored magnetic properties of the perovskite-type oxide heterostructures are important in spintronic devices with low energy consumption and small size. Here, the electric field modulated magnetic properties of underoxidized SrRuO3 (SRO)/SrTiO3 (STO) heterostructures are investigated using first-principles calculations. The spin polarization of underoxidized SRO/STO heterostructures turns from negative to positive as the electric field changes from -0.2 to 0.2 V nm-1. The underoxidized SRO/STO heterostructure with 7 SRO atomic layers turns from perpendicular magnetic anisotropy to in-plane magnetic anisotropy as the electric field turns from -0.2 to 0.2 V nm-1, which can be attributed to the in-plane dx2-y2 and out-of-plane dxz, dyz orbitals. The Dzyaloshinskii-Moriya interaction of underoxidized SRO/STO heterostructures can also be effectively tailored using an electric field. These results indicate that the use of electric field is an effective method to modulate magnetic properties of perovskite-type oxide heterostructures, which is beneficial for the development of the high-performance spintronic devices.

Enhancing the Curie temperature of two-dimensional monolayer CrI3 by introducing I-vacancies and interstitial H-atoms.

The discovery of two-dimensional monolayer CrI3 provides a promising possibility for developing spintronic devices. However, the low Curie temperature is an obstacle for practical applications. Here, based on the consideration of the superexchange interaction of ferromagnetic coupling, we investigate the effect of introducing I-vacancies and interstitial H-atoms on the Curie temperature of monolayer CrI3 by using first-principles calculations and Monte Carlo simulations. Our theoretical conclusions show that the Curie temperature of Cr8I23 (CrI2.875), Cr8I22 (CrI2.75) and Cr8I24H (CrI3H0.125) significantly increases to 97.0, 82.5 and 112.4 K, respectively. Moreover, the magnetic moment of the Cr atom increases from 3.10 to 3.45 and 3.46µB in monolayers Cr8I23 and Cr8I22, respectively. We provide more alternative approaches to effectively enhance the Curie temperature of monolayer CrI3, which will help both theoretical and experimental researchers to directly predict the change in Curie temperature of CrI3 and its analogs through structural information.

Tunable valley polarization, magnetic anisotropy and Dzyaloshinskii-Moriya interaction in two-dimensional intrinsic ferromagnetic Janus 2H-VSeX (X = S, Te) monolayers.

Two-dimensional (2D) Janus materials are a novel kind of 2D materials, which have potential applications in nanoelectronics, optoelectronics and spintronics. However, a 2D Janus material combined with intrinsic ferromagnetism, electric dipole moment, valley polarization and Dzyaloshinskii-Moriya interaction (DMI) remains rarely reported. Here, the electronic structure and magnetic properties of 2D intrinsic ferromagnetic Janus 2H-VSeX (X = S, Te) monolayers are investigated systematically using the density-functional theory. Janus 2H-VSeX (X = S, Te) monolayers are intrinsic ferromagnetic semiconductors with in-plane magnetic anisotropy (IMA). The valley splitting of Janus 2H-VSeX (X = S, Te) monolayers appears by considering the spin-orbit coupling (SOC) effect and out of plane magnetization. Additionally, spontaneous vertical electric dipole moment and a large DMI are also found in Janus 2H-VSeX (X = S, Te) monolayers due to the broken inversion symmetry. Moreover, the valley splitting and DMI can be significantly increased by applying in-plane biaxial strain. These results provide an interesting 2D intrinsic ferromagnetic Janus material, which has potential applications in spintronic and valleytronic devices.

Electronic structure, magnetic anisotropy and Dzyaloshinskii-Moriya interaction in Janus Cr2I3X3 (X = Br, Cl) bilayers.

Two-dimensional (2D) layers with a tunable electronic structure and magnetic properties have attracted much attention due to their unique characteristics and practical applications. Here, the electronic structure and magnetic properties of the 2D van der Waals Cr2I3X3 (X = Br, Cl) bilayers are investigated systematically by first-principles calculations. The Cr2I3X3 bilayers show the stacking-dependent magnetic ground state, where the band gap can be effectively tailored by the stacking and combination modes. In the Cr2I3Br3 (Cr2I3Cl3) bilayers, the electrostatic potential and electric polarization can be greatly affected by combination modes, which can be attributed to the parallel or antiparallel built-in electric fields between the monolayers. The Cr2I3X3 bilayers show a perpendicular magnetic anisotropy. The magnetic anisotropy energy of the Cr2I3Cl3 bilayer is larger than that of the Cr2I3Br3 bilayer, which can be attributed to the enhanced contribution of the hybridized I px and py orbitals of the Cr2I3Cl3 bilayer. Additionally, the Dzyaloshinskii-Moriya interaction of the Cr2I3Br3 bilayer can also be modulated by the combination modes. These results can boost the development of Janus 2D materials, which are useful in the design of multifunctional spintronic devices.

Regulating the Spin State of FeIII by Atomically Anchoring on Ultrathin Titanium Dioxide for Efficient Oxygen Evolution Electrocatalysis.

Ferric oxides and (oxy)hydroxides, although plentiful and low-cost, are rarely considered for oxygen evolution reaction (OER) owing to the too high spin state (eg filling ca. 2.0) suppressing the bonding strength with reaction intermediates. Now, a facile adsorption-oxidation strategy is used to anchor FeIII atomically on an ultrathin TiO2 nanobelt to synergistically lower the spin state (eg filling ca. 1.08) to enhance the adsorption with oxygen-containing intermediates and improve the electro-conductibility for lower ohmic loss. The electronic structure of the catalyst is predicted by DFT calculation and perfectly confirmed by experimental results. The catalyst exhibits superior performance for OER with overpotential 270 mV @10 mA cm-2 and 376 mV @100 mA cm-2 in alkaline solution, which is much better than IrO2 /C and RuO2 /C and is the best iron-based OER catalyst free of active metals such as Ni, Co, or precious metals.

2D Semiconducting Metal-Organic Framework Thin Films for Organic Spin Valves.

2D conductive metal-organic frameworks (2D c-MOFs) feature promising applications as chemiresistive sensors, electrode materials, electrocatalysts, and electronic devices. However, exploration of the spin-polarized transport in this emerging materials and development of the relevant spintronics have not yet been implemented. In this work, layer-by-layer assembly was applied to fabricate highly crystalline and oriented thin films of a 2D c-MOF, Cu3 (HHTP)2 , (HHTP: 2,3,6,7,10,11-hexahydroxytriphenylene), with tunable thicknesses on the La0.67 Sr0.33 MnO3 (LSMO) ferromagnetic electrode. The magnetoresistance (MR) of the LSMO/Cu3 (HHTP)2 /Co organic spin valves (OSVs) reaches up to 25 % at 10 K. The MR can be retained with good film thickness adaptability varied from 30 to 100 nm and also at high temperatures (up to 200 K). This work demonstrates the first potential applications of 2D c-MOFs in spintronics.

Electronic transport properties and magnetoresistance in the Fe3O4/SiO2/p-Si heterostructure with an in-plane current geometry.

In traditional electronic devices, the electronic charge is manipulated to realize different functions. The fascinating control of electronic spin in conventional semiconductors increases the probability of occurrence of spin-dependent transport properties. Herein, the injection of electronic spin into a Si wafer with in-plane geometry was achieved by Fe3O4, which acted as a spin injector. At high temperatures, the resistivity of Fe3O4 is far less than that of a p-Si wafer. Moreover, above 190 K, the current-voltage (I-V) characteristic and magnetoresistance (MR) of the proposed heterostructure are dominated by the intrinsic properties of a polycrystalline Fe3O4 film, and the in-plane current flows in the Fe3O4 layer. Due to the increased resistivity of Fe3O4 at low temperatures, the in-plane conductive channel gradually switches from Fe3O4 to Si. The spin injection from Fe3O4 results in a spin-polarized space charge region in p-Si. The heterostructure shows an MR of up to -76.1% at 90 K due to the spin-dependent transport of electrons in p-Si. With a further decrease in temperature, the I-V characteristic of the heterostructure shows negative differential resistance below 80 K due to band bending at the Fe3O4/SiO2/p-Si interface.

Magnetic proximity effect induced spin-dependent electronic structure in two-dimensional SnO by half-metallic monolayer CrN ferromagnet.

Monolayer SnO has been attracting much attention owing to its unique electronic structure, which has potential applications in nanoelectronic and optoelectronic devices. However, it is necessary to induce the spin-dependent electronic structure of monolayer SnO for its applications in spintronics. Here, in order to induce the spin polarization of monolayer SnO by magnetic proximity effects, the spin-dependent electronic structure of two-dimensional (2D) van der Waals (vdW) SnO/CrN heterostructures is calculated using first-principles calculations by considering different strains and interlayer distances. When the interlayer distance of the heterostructure increases, the Sn magnetic moment decreases, but the Cr magnetic moment increases. As the interlayer distance decreases, the band gap of SnO decreases in the spin-down channel because of the enhancements in orbital overlap and hybridization. Meanwhile, the electronic structure of monolayer SnO/CrN heterostructures can also be tailored by in-plane biaxial strain. With an increase in tensile strain, the Fermi level of monolayer SnO moves down and p-type doping appears. For compressive strains, the Fermi level of monolayer SnO moves upward and n-type doping appears. When the in-plane biaxial strain turns from compressive to tensile, the magnetic anisotropy of CrN in monolayer SnO/CrN heterostructure increases, where the easy axis is perpendicular to the CrN layer.

Efficient band structure modulations in two-dimensional MnPSe3/CrSiTe3 van der Waals heterostructures.

As a research upsurge, van der Waals (vdW) heterostructures give rise to numerous combined merits and novel applications in nanoelectronics fields. Here, we systematically investigate the electronic structure of MnPSe3/CrSiTe3 vdW heterostructures with various stacking patterns. Then, particular attention of this work is paid on the band structure modulations in MnPSe3/CrSiTe3 vdW heterostructures via biaxial strain or electric field. Under a tensile strain, the relative band edge positions of heterostructures transform from type-I (nested) to type-II (staggered). The relocation of conduction band minimum also brings about a transition from indirect to direct band gap. Under a compressive strain, the electronic properties change from semiconducting to metallic. The physical mechanism of strain-dependent band structure may be ascribed to the shifts of the energy bands impelled by different superposition of atomic orbitals. Meanwhile, our calculations manifest that band gap values of MnPSe3/CrSiTe3 heterostructures are insensitive to the electric field. Even so, by applying a suitable intensity of negative electric field, the band alignment transition from type-I to type-II can also be realized. The efficient band structure modulations via external factors endow MnPSe3/CrSiTe3 heterostructures with great potential in novel applications, such as strain sensors, photocatalysis, spintronic and photoelectronic devices.

Spin polarization and spin channel reversal in graphitic carbon nitrides on top of an α-Fe2O3(0001) surface.

Inducing the spin-dependent characteristics in two-dimensional (2D) materials by magnetic proximity effects is a recent targeted route for 2D spintronic devices. Here, we report the spin-dependent electronic properties of graphitic carbon nitrides (g-C2N, g-C3N and g-C4N3) on top of α-Fe2O3(0001) by first-principles calculations. The different terminations of α-Fe2O3(0001) can switch the conductivity of g-C2N from the n- to the p-type. In particular, the O- and single Fe-terminated interfaces show a half-metallic feature in g-C2N, which originates from the charge redistribution driven by work function difference and interfacial interaction. Additionally, the O-terminated interface shows stable physical adsorption, which leads to spin polarization in g-C3N and spin channel reversal in g-C4N3. These results strongly reveal that this novel system is a candidate for future graphitic carbon nitride-based spintronic devices.

Spin-orbit coupling induced spin polarized valley states in SrRuO3/BiIrO3 heterostructures.

The electronic properties of SrRuO3/BiIrO3 superlattices are investigated by first-principles calculations with spin-orbit coupling. The results show that the strength of hybridization near the Fermi level is dependent on the distance between the closest transition metal Ru and Ir atoms. We find that both spin and valley polarizations in bilayered BiIrO3 are achieved in Bi-terminated models. Furthermore, different stacking patterns can modulate the magnitude and sign of valley polarization and switch the p- or n-type doping of bilayered BiIrO3. Meanwhile, a spin-down polarized valley polarization of 79.5 meV can be induced in bilayered SrRuO3. The different thicknesses calculated demonstrate that the valley in the SrRuO3/BiIrO3 model is limited to the bilayered structure. The tunable valley and spin polarizations in SrRuO3/BiIrO3 superlattices would enrich the diversity and boost the development of high-performance spintronic and valleytronic devices.

Spin splitting and p-/n-type doping of two-dimensional WSe2/BiIrO3(111) heterostructures.

The electronic structure of monolayer WSe2/BiIrO3(111) interfaces is investigated by first-principles calculations. The different polar directions of bilayer BiIrO3(111) can induce the p- or n-type doping of WSe2, indicating that the conductivity of monolayer WSe2 can be effectively modulated by switching the polarization of bilayer BiIrO3(111). Meanwhile, in B1 and B4 models, the spin splitting energies of WSe2 are 413.7 and 416.6 meV, which decrease by 52.9 and 50.0 meV compared to that of pristine monolayer WSe2 of 466.6 meV. Additionally, by applying a perpendicular electric field of 0.1 V nm-1, the spin splitting can be increased from 413.7 to 421.5 meV. However, spin splitting shows robustness against large electric fields. The results are useful in the design of novel two-dimensional transition metal dichalcogenide devices.