Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

First-Principles Investigation of Phase Stability, Electronic Structure and Optical Properties of MgZnO Monolayer.

ABSTRACT: MgZnO bulk has attracted much attention as candidates for application in optoelectronic devices in the blue and ultraviolet region. However, there has been no reported study regarding two-dimensional MgZnO monolayer in spite of its unique properties due to quantum confinement effect. Here, using density functional theory calculations, we investigated the phase stability, electronic structure and optical properties of MgxZn1-xO monolayer with Mg concentration x range from 0 to 1. Our calculations show that MgZnO monolayer remains the graphene-like structure with various Mg concentrations. The phase segregation occurring in bulk systems has not been observed in the monolayer due to size effect, which is advantageous for application. Moreover, MgZnO monolayer exhibits interesting tuning of electronic structure and optical properties with Mg concentration. The band gap increases with increasing Mg concentration. More interestingly, a direct to indirect band gap transition is observed for MgZnO monolayer when Mg concentration is higher than 75 at %. We also predict that Mg doping leads to a blue shift of the optical absorption peaks. Our results may provide guidance for designing the growth process and potential application of MgZnO monolayer.

SUBMITTER: Tan C

PROVIDER: S-EPMC5457241 | biostudies-other | 2016 Oct

REPOSITORIES: biostudies-other

ACCESS DATA

Json Xml

Similar Datasets

Structural, electronic, and optical properties of cubic formamidinium lead iodide perovskite: a first-principles investigation.

Project description:Hybrid organic-inorganic perovskites have been one of the most active areas of research into photovoltaic materials. Despite the extremely fast progress in this field, the electronic properties of formamidinium lead iodide perovskite (FAPbI3) that are key to its photovoltaic performance are relatively poorly understood when compared to those of methylammonium lead iodide (MAPbI3). In this study, first-principles total energy calculations based on density functional theory were used to investigate the favored orientation of FA. Different theoretical methods, with or without incorporation of spin-orbit coupling (SOC) effects, were used to study the structure, electronic properties, and charge-carrier effective mass. Also the SOC-induced Rashba k-dependent band splitting, density of states and optical properties are presented and discussed. These results are useful for understanding organic-inorganic lead trihalide perovskites and can inform the search for new materials and design rules.

| S-EPMC9056641 | biostudies-literature

Electronic and Near-Infrared-II Optical Properties of I-Doped Monolayer MoTe<sub>2</sub>: A First-Principles Study.

Project description:Near-infrared-II (NIR-II, 1000-1700 nm) fluorescence imaging is widely used for in vivo biological imaging. With the unique electronic structures and capability of band-gap engineering, two-dimensional (2D) materials can be potential candidates for NIR-II imaging. Herein, a theoretical investigation of the electronic structure and optical properties of iodine (I)-doped monolayer MoTe2 systems with different doping concentrations is carried out through simulations to explore their NIR optical properties. The results suggest that the emergence of impurity levels due to I doping effectively reduces the bandwidth of I-doped monolayer MoTe2 systems, and the bandwidth decreases with the increase in the I doping concentration. Although the I and Mo atoms possess clear covalent-bonding features according to the charge density difference, impurity levels induced by the strong hybridization between the I 5p and Mo 4d orbitals cross the Fermi level, making the doped systems exhibit metallic behavior. In addition, with the increase in the I doping concentration, the energy required for electron transition from valence bands to impurity levels gradually decreases, which can be linked to the enhancement of the optical absorption in the red-shifted NIR-II region. Meanwhile, with a higher I doping concentration, the emission spectra, which are the product of the absorption spectra and quasi-Fermi distributions for electrons and holes, can be enhanced in the NIR-II window.

| S-EPMC9016853 | biostudies-literature

First-Principles Investigation of the Structural, Elastic, Electronic, and Optical Properties of ?- and ?-SrZrS3: Implications for Photovoltaic Applications.

Project description:Transition metal perovskite chalcogenides are attractive solar absorber materials for renewable energy applications. Herein, we present the first-principles screened hybrid density functional theory analyses of the structural, elastic, electronic and optical properties of the two structure modifications of strontium zirconium sulfide (needle-like ?-SrZrS3 and distorted ?-SrZrS3 phases). Through the analysis of the predicted electronic structures, we show that both ?- and ?-SrZrS3 materials are direct band gaps absorbers, with calculated band gaps of 1.38, and 1.95 eV, respectively, in close agreement with estimates from diffuse-reflectance measurements. A strong light absorption in the visible region is predicted for the ?- and ?-SrZrS3, as reflected in their high optical absorbance (in the order of 105 cm-1), with the ?-SrZrS3 phase showing stronger absorption than the ?-SrZrS3 phase. We also report the first theoretical prediction of effective masses of photo-generated charge carriers in ?- and ?-SrZrS3 materials. Predicted small effective masses of holes and electrons at the valence, and conduction bands, respectively, point to high mobility (high conductivity) and low recombination rate of photo-generated charge carriers in ?- and ?-SrZrS3 materials, which are necessary for efficient photovoltaic conversion.

| S-EPMC7079647 | biostudies-literature

First-principles study of nonmetal doped monolayer MoSe2 for tunable electronic and photocatalytic properties.

Project description:Recently, two dimensional transition metal dichalcogenides become popular research topics because of their unique crystal and electronic structure. In this work, the geometrical structure, electronic, electrical transport, redox potentials and photocatalytic properties of nonmetal (H, B, C, Si, N, P, As, O, S, Te, F, Cl, Br and I) doped monolayer MoSe2 were investigated by first principle calculations. The binding energy indicates that nonmetal doped MoSe2 are energetically favorable compared to Se vacancies, except B- and C-doped. We have found that nonmetal dopants with an even number of valence electrons doped MoSe2 have p-type conductivity. On the contrary, nonmetal dopants with an odd number of valence electrons doped MoSe2 have p-type or n-type conductivity; and they have better photocatalytic performance.

| S-EPMC5719077 | biostudies-literature

Electronic and Optical Properties of Two-Dimensional Tellurene: From First-Principles Calculations.

Project description:Tellurene is a new-emerging two-dimensional anisotropic semiconductor, with fascinating electric and optical properties that differ dramatically from the bulk counterpart. In this work, the layer dependent electronic and optical properties of few-layer Tellurene has been calculated with the density functional theory (DFT). It shows that the band gap of the Tellurene changes from direct to indirect when layer number changes from monolayer (1 L) to few-layers (2 L-6 L) due to structural reconstruction. Tellurene also has an energy gap that can be tuned from 1.0 eV (1 L) to 0.3 eV (6 L). Furthermore, due to the interplay of spin-orbit coupling (SOC) and disappearance of inversion symmetry in odd-numbered layer structures resulting in the anisotropic SOC splitting, the decrease of the band gap with an increasing layer number is not monotonic but rather shows an odd-even quantum confinement effect. The optical results in Tellurene are layer dependent and different in E ? C and E || C directions. The correlations between the structure, the electronic and optical properties of the Tellurene have been identified. Despite the weak nature of interlayer forces in their structure, their electronic and optical properties are highly dependent on the number of layers and highly anisotropic. These results are essential in the realization of its full potential and recommended for experimental exploration.

| S-EPMC6722590 | biostudies-literature

First-Principles Study of Penta-PtXY (X = Se, Te; Y = S, Te; X = Y) Monolayer with Highly Anisotropic Electronic and Optical Properties.

Project description:Two-dimensional (2D) semiconducting materials with anisotropic physical properties have induced lively interest due to their application in the field of polarizing devices. Herein, we have designed a family of penta-PtXY (X = Se, Te; Y = S, Te; X ≠ Y) monolayers and predicted the electronic and optical properties based on the first-principles calculation. The results suggest that the penta-PtXY (X = Se, Te; Y = S, Te; X ≠ Y) monolayers are indirect-gap semiconductors with a medium bandgap of 2.29-2.66 eV. The penta-PtXY (X = Se, Te; Y = S, Te; X ≠ Y) monolayers own a remarkable mechanical anisotropy with a high Young's modulus anisotropic ratio (3.0). In addition, the penta-PtXY (X = Se, Te; Y = S, Te; X ≠ Y) monolayers exhibit a high anisotropy ratio of hole/electron mobility in the x and y directions (1.16-3.54). The results calculated by the G0W0+BSE method indicate that the single-layers also bear a salient optical anisotropy ratio (1.56-2.11). The integration of the anisotropic electronic, optical, and mechanical properties entitles penta-PtXY (X = Se, Te; Y = S, Te; X ≠ Y) monolayers as potential candidates in multifunctional polarized nanodevices.

| S-EPMC11292839 | biostudies-literature

Point Defects Stability, Hydrogen Diffusion, Electronic Structure, and Mechanical Properties of Defected Equiatomic γ(U,Zr) from First-Principles.

Project description:At present, many experimental fast reactors have adopted alloy nuclear fuels, for example, U-Zr alloy fuels. During the neutron irradiation process, vacancies and hydrogen (H) impurity atoms can both exist in U-Zr alloy fuels. Here, first-principles density functional theory (DFT) is employed to study the behaviors of vacancies and H atoms in disordered-γ(U,Zr) as well as their impacts on the electronic structure and mechanical properties. The formation energy of vacancies and hydrogen solution energy are calculated. The effect of vacancies on the migration barrier of hydrogen atoms is revealed. The effect of vacancies and hydrogen atom on densities of states and elastic constants are also presented. The results illustrate that U vacancy is easier to be formed than Zr vacancy. The H interstitial prefers the tetrahedral site. Besides, U vacancy shows H-trap ability and can raise the H migration barrier. Almost all the defects lead to decreases in electrical conductivity and bulk modulus. It is also found that the main effect of defects is on the U-5f orbitals. This work provides a theoretical understanding of the effect of defects on the electronic and mechanical properties of U-Zr alloys, which is an essential step toward tailoring their performance.

| S-EPMC9656540 | biostudies-literature

A first principles investigation on the structural, mechanical, electronic, and catalytic properties of biphenylene.

Project description:Recently, a new two-dimensional allotrope of carbon (biphenylene) was experimentally synthesized. Using first-principles calculations, we systematically investigated the structural, mechanical, electronic, and HER properties of biphenylene. A large cohesive energy, absence of imaginary phonon frequencies, and an ultrahigh melting point up to 4500 K demonstrate its high stability. Biphenylene exhibits a maximum Young's modulus of 259.7 N/m, manifesting its robust mechanical performance. Furthermore, biphenylene was found to be metallic with a n-type Dirac cone, and it exhibited improved HER performance over that of graphene. Our findings suggest that biphenylene is a promising material with potential applications in many important fields, such as chemical catalysis.

| S-EPMC8463688 | biostudies-literature

First-principles insights on the electronic and optical properties of ZnO@CNT core@shell nanostructure.

Project description:In recent years, various kinds of ZnO-based core@shell nanomaterials have been paid much attention due to their widespread applications in the fields of physics, chemistry and energy conversion. In this work, the electronic and optical properties of a new type of ZnO-based one-dimensional core@shell nanostructure, which is composed of inner ZnO nanowire and outer carbon nanotube (CNT), is calculated based on the first-principles density functional theory (DFT). Calculation results suggest that the ZnO nanowire encapsulated in (9, 9)-CNT is the most stable structure from the view of formation energy. The interaction between the inner ZnO nanowire and the outer (9, 9) CNT belongs to a weak van der Waals type. The complex structure is found to possess metallicity for the outer (9, 9) CNT and maintain the wide band gap nature for the inner ZnO nanowire. Under the different external strains, the charge redistribution between inner ZnO nanowire and outer CNT caused by electron tunneling leads to the shift of Dirac point and the band narrowing of inner ZnO nanowire. The inner ZnO nanowire only has light absorption in the UV region, which is consistent with its optical property originating from its wide bandgap nature.

| S-EPMC6194084 | biostudies-literature

Anisotropic optical properties induced by uniaxial strain of monolayer C<sub>3</sub>N: a first-principles study.

Project description:The optical properties, structural properties and electronic properties of a new two-dimensional (2D) monolayer C3N under different strains are studied in this paper by using first-principles calculations. The applied strain includes in-layer biaxial strain and uniaxial strain. The monolayer C3N is composed of a number of hexagonal C rings with N atoms connecting them. It is a stable indirect band gap 2D semiconductor when the strain is 0%. It could maintain indirect semiconductive character under different biaxial and uniaxial strains from ε = -10% to ε = 10%. As for its optical properties, when the uniaxial strain is applied, the absorption and reflectivity along the armchair and zigzag directions exhibit an anisotropic property. However, an isotropic property is presented when the biaxial strain is applied. Most importantly, both uniaxial tensile strain and biaxial tensile strain could cause the high absorption coefficient of monolayer C3N to be in the deep ultraviolet region. This study implies that strain engineering is an effective approach to alter the electronic and optical properties of monolayer C3N. We suggest that monolayer C3N could be suitable for applications in optoelectronics and nanoelectronics.

| S-EPMC9063800 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data