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The first-principles approach was used to investigate the effect of doping with non-metallic elements (B, C, and N) on the optoelectronic properties of 1T-SnS2 monolayers and homojunction. We discussed the changes in geometry, energy band structure, complex dielectric function, absorption properties, and reflection coefficients. The calculation results of formation energy indicate that the N-doped system has a minor formation energy of –1.452 and –1.023 eV in the monolayer and homojunction, respectively, which suggests that N-doping is the easiest to realize. In the monolayer structure, B-doping leads to the transition from semiconductor to metal system, while C-doping and N-doping result in the narrowing of the band gap. In the bilayer structure, B-doping and N-doping turn the system into metallicity, while C-doping eventuates more significant band gap reduction. In addition, the results of optical properties show that N-doping has a more significant effect on increasing the reflectivity of SnS2 monolayer and homogeneous structures compared to B and C doping. These findings help us better understand the effect of non-metallic element doping on SnS2 and provide an essential theoretical reference for the potential application of SnS2 in microelectronic devices, which is of practical significance for material design and performance improvement. [ABSTRACT FROM AUTHOR]

In this paper, we calculate the optical and electronic properties of ZrS2/ZrSe2 heterostructures under intrinsic and biaxial tensile strain using the first-principles calculation method based on plane wave density functional theory. The photoelectric properties of ZrS2/ZrSe2 heterojunction and single-layer ZrX2 (X = S, Se) structure are analyzed. The results show that the heterostructure has an adjustable band gap and stronger optical absorption capacity and light reflectivity in photoelectric properties. The ZrS2/ZrSe2 heterostructure under tensile strain significantly improves optical absorption capacity and light reflectivity. The ZrS2/ZrSe2 heterostructure under tensile strain has stronger optical absorption and reflection ability than the single-layer ZrX2 (X = S, Se) structure. The results provide a new theoretical reference for the applying ZrS2/ZrSe2 heterostructures in optoelectronic devices. [ABSTRACT FROM AUTHOR]

Based on first principles, the effect of biaxial tensile strain on the electronic structure and optical properties of 1T-CrS2 doped with nonmetallic elements (B, C, and Si) has been studied. The monolayer CrS2 system exhibits an indirect band gap when subjected to tensile strain and Si doping. The direct bandgaps of the B and C doped systems are 0.125 and 0.167 eV, respectively, and the formation energies of both are negative, indicating that the systems are simple to form. Further bandgap modulation is accomplished under tensile strain for the doped systems. The B- and C-doped systems are capable of bandgap-type conversion under tensile strain. The study of the optical properties shows that atomic doping alters the optical response of the system, and a slight absorption band edge appears in the absorption spectrum. At minimal strain (2%), the optical properties of the doped system improved, thereby enhancing the photocatalytic activity of the compounds. The aforementioned findings inform the use of the material in microelectronics and particular optical domains. [ABSTRACT FROM AUTHOR]

Context: Based on the first principles under the framework of density functional theory, it calculates the effect of vacancy defects in single Zr and single Se atoms and the replacement of Se atoms in ZrSe2 with O, Se, and Te atoms on the optoelectronic properties of monolayer ZrSe2, including geometry, energy band structure, electronic density of states, and optical properties. The doping of the three non-metallic atoms was n-type doping for the O and S atoms and p-type doping for the Te atom. Defects in the Zr atoms and O-atom doping significantly affect the peak reflectance and absorption coefficient of the ZrSe2 system. Methods: All Density Functional Theory calculations were carried out using the CASTEP module in the Materials-Studio (MS) software. The generalized gradient approximation plane-wave pseudopotential method and the Perdew-Burke-Ernzerfhof (PBE) generalized function were used for structural optimization and total energy calculation of the defect and doping systems. After convergence tests, the plane wave truncation energy was set to 500 eV, and the Brillouin zone K-point grid was set to 4 × 4 × 1. The atomic energy convergence criterion is 1.0 × 10−6 eV/atom, the interatomic interaction force convergence criterion is 0.02 eV/Å, the maximum atomic displacement convergence criterion is 0.001 Å, and the internal crystal stress convergence criterion is 0.05 GPa. In order to avoid the influence of the interaction forces between the layers, a vacuum layer of 15 Å is placed in the Z-axis direction. [ABSTRACT FROM AUTHOR]

Context: Monolayer NbS2 is a promising new two-dimensional material, and it is critical to develop effective methods to make NbS2 a material for nanodevices and photovoltaic applications. This study studied the strain rule of sulfur-deficient NbS2 structure by first principles. The results show that all defect structures introduce impurity states to enhance electron transport. The disulfide defect structure produces an indirect band gap under the action of tensile strain, which can reach up to 0.56eV and become a diluted semiconductor. The hybrid NbS2 exhibits high transparency under infrared, visible, and low-frequency ultraviolet light, improving the material's transmittance, optical response, and catalytic activity. The research results of this paper will provide a basis for the subsequent research of single-layer NbS2 and accelerate the research process of NbS2 as a new semiconductor material. Methods: We are on the surface perpendicular to the 3×3×1 NbS2 and use a 15 Å vacuum layer to avoid interacting with periodic images. The first-principles simulation uses the CASTEP module in Materials Studio to simulate the hypothetical model and relaxation optimization structure of single-layer NbS2 under strain and defect state. The calculation function is PBE (Perdew-Burke-Ernzerhof) function under the generalized gradient approximation (GGA) for an approximate calculation to describe the interaction between electrons and the interaction between electrons and ions. The pseudopotentials of 3s23p4 and 4d45s1 valence electron configurations were used for S and Nb atoms, respectively. Van der Waals correction is considered in the simulation process. Moreover, it includes spin-orbit coupling (SOC) effects. For the plane wave truncation energy, we set it at 500eV. The arrangement of the Brillouin area is divided by 6×6×1 gamma-centered Monkhorst-Pack grids. The lattice deformation of all hybrid structures is less than 0.05 Gpa, and the interatomic force is less than 0.03 eV/Å. [ABSTRACT FROM AUTHOR]

In this paper, the effects of doping VIA group non-metallic elements (O, Se, Te) on the optoelectronic properties of monolayer 1T-ZrS2 were calculated using a first-principles approach. The results showed that the doped atoms could successfully modulate the band gap of monolayer 1T-ZrS2. By applying biaxial tensile strain in the x–y direction, it is found that the band gap of the pristine monolayer 1T-ZrS2 increases first and then decreases, reaching the maximum at 6%. On this basis, a further 6% tensile strain was applied to the three doped systems. It was found that after applying strain, the band gap of all doped systems increased, and the indirect band gap changed to a direct band gap, improving the luminescence efficiency of the materials. The analysis of the optical properties revealed that all systems have a high reflectance of photons in the near ultraviolet region, which had a considerable impact on the transmittance. The study's findings offer a theoretical guide for using monolayer 1T-ZrS2 in microelectronic devices. [ABSTRACT FROM AUTHOR]

Plant architecture and panicle architecture are two critical agronomic traits that greatly affect the yield of rice (Oryza sativa). PROSTRATE GROWTH 1 (PROG1) encodes a key C2H2-type zinc-finger transcription factor and has pleiotropic effects on the regulation of both plant and panicle architecture, thereby influencing the grain yield. However, the molecular mechanisms through which PROG1 controls plant and panicle architecture remain unclear. In this study, we showed that PROG1 directly binds the LAZY 1 (LA1) promoter and acts as a repressor to inhibit LA1 expression. Conversely, LA1 acts as a repressor of PROG1 by directly binding to the PROG1 promoter. These two genes play antagonistic roles in shaping plant architecture by regulating both tiller angle and tiller number. Interestingly, our data showed that PROG1 controls panicle architecture through direct binding to the intragenic regulatory regions of OsGIGANTEA (OsGI) and subsequent activation of its expression. Collectively, we have identified two crucial targets of PROG1, LA1 and OsGI , shedding light on the molecular mechanisms underlying plant and panicle architecture control by PROG1. Our study provides valuable insights into the regulation of key domestication-related traits in rice and identifies potential targets for future high-yield rice breeding. During rice domestication, inactivation of PROG1 resulted in critical changes such as an erect plant shape and enlarged panicles, ultimately leading to higher yield. This study identified LA1 and OsGI as the downstream targets of PROG1 responsible for these changes, shedding light on the molecular mechanism underlying PROG1-driven regulation of plant and panicle changes during rice domestication and providing new breeding targets. [ABSTRACT FROM AUTHOR]

The effects of vacancy defects and torsion on the optoelectronic properties of single-layered 1 T -TaS2, including the band structure, electron density difference, defect formation energy and complex dielectric function, are systematically investigated using the first-principles method based on density functional theory (DFT). The results show that vacancy defects cause relaxation of surrounding atoms leading to local distortions in the structure and changes in bond length, and the formation energy of the V S system is significantly lower than theV 2 S system, which is easier to achieve the single sulfur-atom vacancy in the experiment. The vacancies system successfully opens a narrow bandgap under torsion, where the V S system shows a decreasing trend in the range of 2–8 ∘ , increasing after 10 ∘ , while V 2 S systems keep increasing. Meanwhile, we found that the optical properties of 1 T -TaS2 monolayer are closely related to defects and torsion. The results show that the static dielectric constant, the maximum of the imaginary part, initial absorption coefficient and reflectivity of 1 T -TaS2 monolayer gradually increases with torsion. The spectra of vacancy systems are all elevated in the low-frequency band, indicating that the vacancy defects have improved the properties of the visible region. The significant decrease after 5 eV indicates that the torsion substantially affects the properties in the UV region. [ABSTRACT FROM AUTHOR]

This paper modulates the band structure of 1T-HfS2 by doping with non-metallic atoms of group IIIA to VIIA of the second period (B, C, N, O, and F atoms) and using biaxial tensile strain in the x–y direction. The optoelectronic properties of the material, including the formation energy, electronic structure, and complex dielectric function, are analyzed based on the first-principles calculations. The results show that n‑type doping is achieved in B-doping and F-doping, and C-doping, N-doping, and O-doping belong to p‑type doping. When B and C atoms are doped, the strong hybridization between the impurity atoms and the Hf atoms causes impurity levels to be introduced in the forbidden band, which has an essential effect on the system's conductivity. Under biaxial tensile strain, the bandgaps of the system of the N-doping, O-doping, and F-doping increase, and the type of bandgap changes from indirect to direct, which improves the luminous efficiency of the material. The formation energy calculations also show that the N-doping and O-doping are easier to form with –2.108 and –2.813 eV, respectively. In addition, the study of the optical properties shows that tensile strain shifts the optical properties of all systems in the low-energy region. The results provide a theoretical reference for applying monolayer 1T-HfS2 in microelectronic devices. [ABSTRACT FROM AUTHOR]

In this paper, the effect of substitutional doping of boron (B), carbon (C), nitrogen (N), oxygen (O), and phosphorus (P) at the S-site on the electronic structure of the monolayer TiS2 system is investigated using a first-principles calculation method. The effect of nonmetal doping on the band gap of TiS2 and its mechanism were studied by analyzing the stability, electronic structure, and charge transfer of the system. By calculating the electron cloud overlap population and formation energy, we confirmed that the system is stable, and the Ti–X bond length of the doped system undergoes different degrees of distortion. The properties of the B, C, and N doped system show different properties with different doping concentrations; the band gap of the O-atom system gradually expands with the rise of the doping rate. The hybridization positions of the impurity and the intrinsic atoms are found by comparing the DOS; combined with the charge density difference, we confirmed the interaction of impurity atoms with the system and revealed the bonding process of different systems. [ABSTRACT FROM AUTHOR]

Summary: The specification of the meristem/organ boundary is critical for plant development. Here, we investigate two previously uncharacterized NAC transcription factors: the first, OsCUC1, which is negatively regulated by osa‐miR164c, dimerizes with the second, OsCUC3, and functions partially redundantly in meristem/organ boundary specification in rice (Oryza sativa).We produced knockout lines for rice OsCUC1 (the homolog of Arabidopsis CUC1 and CUC2) and OsCUC3 (the homolog of Arabidopsis CUC3), as well as an overexpression line for osa‐miR164c, to study the molecular mechanism of boundary specification in rice.A single mutation in either OsCUC1 or OsCUC3 leads to defects in the establishment of the meristem/organ boundary, resulting in reduced stamen numbers and the fusion of leaves and filaments, and the defects are greatly enhanced in the double mutant. Transgenic plants overexpressing osa‐miR164c showed a phenotype similar to that of the OsCUC1 knockout line. In addition, knockout of OsCUC1 leads to multiple defects, including dwarf plant architecture, male sterility and twisted‐rolling leaves. Further study indicated that OsCUC1 physically interacts with leaf‐rolling related protein CURLED LEAF AND DWARF 1 (CLD1) and stabilizes it in the nucleus to control leaf morphology.This work demonstrated that the interplay of osa‐miR164c, OsCUC1 and OsCUC3 controls boundary specification in rice. [ABSTRACT FROM AUTHOR]

This paper investigated the performance changes brought about by the adsorption of metal and non-metal atoms on monolayer NbS 2 . First-principles found that the adsorption of non-metallic atoms on the monolayer NbS 2 significantly changed the surface structure, with non-metallic atoms other than F intercalated into the upper S atoms. Among them, the F atom adsorption modification system changed the metallic properties of NbS 2 and tended to transform into a semiconductor. Fe and Co atoms effectively change the real part of the dielectric constant, transforming NbS 2 into a metamaterial. The adsorption of noble metal atoms can improve the activity of the material. Furthermore, F(Fe, Co) atoms can induce p(n)-type doping by adjusting strain. N adsorption expands the system's electromagnetic wave absorption range and improves the material's electrical conductivity. O and Pt adsorption significantly enhanced the polarizability and photoresponse of the material, resulting in enhanced photocatalytic activity., (© 2022 IOP Publishing Ltd.)