Roles of Oxygen Vacancies in NiMoO4: A First-Principles Study

Oxygen vacancy has been suggested to play a role in the electrochemical ability of NiMoO4. The band structure and density of state of NiMoO4 bulks with different concentrations of oxygen vacancy were investigated by the first-principles calculation. Original NiMoO4 shows semiconductive properties with a direct band gap of 0.136 eV. When one to three oxygen vacancies were introduced in the NiMoO4 supercell, the band structure of NiMoO4 transforms to metallic properties, and oxygen vacancies formation energy increases with the increased number of oxygen vacancies. The oxygen vacancies in NiMoO4 lead to the increased electron localization of Ni 3d and Mo 3d state nearby the Fermi level, resulting in higher concentration of carriers in NiMoO4 and thus increase in its electrical conductivity. The results demonstrate that introducing oxygen vacancies can improve the conductive property of NiMoO4.

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Formation of oxygen vacancies in Li2FeSiO4: first-principles calculations

Physical Chemistry Chemical Physics ◽

10.1039/d1cp02539b ◽

2021 ◽

Vol 23 (36) ◽

pp. 20444-20452

Author(s):

Lihong Zhang ◽

Shunqing Wu ◽

Jianwei Shuai ◽

Zhufeng Hou ◽

Zizhong Zhu

Keyword(s):

Oxygen Vacancy ◽

First Principles ◽

Formation Energy ◽

Oxygen Vacancies ◽

Vacancy Formation Energy ◽

Vacancy Formation ◽

First Principles Calculations ◽

Temperature And Pressure

The oxygen vacancy (left panel) and the vacancy formation energy as a function of temperature and pressure (right panel).

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First principles study of oxygen vacancies in (Mo + C)-doped anatase TiO2

Modern Physics Letters B ◽

10.1142/s0217984915500724 ◽

2015 ◽

Vol 29 (14) ◽

pp. 1550072 ◽

Cited By ~ 2

Author(s):

Jie Cui ◽

Shuhua Liang ◽

Xianhui Wang ◽

Jianmin Zhang

Keyword(s):

Oxygen Vacancy ◽

Fermi Level ◽

Conduction Band ◽

First Principles ◽

Formation Energy ◽

Oxygen Vacancies ◽

Anatase Tio2 ◽

Metallic Behavior ◽

Structural And Electronic Properties ◽

Projector Augmented Wave

The structural and electronic properties of neutral oxygen vacancies in ( Mo + C )-doped anatase TiO 2 were investigated using frozen-core projector-augmented wave (PAW) method within GGA +U approximation. Six possible oxygen vacancy sites were considered in the present work. The results show that the octahedral vertex adjacent to Mo and opposite from C is the most stable position for oxygen vacancy based on the results of the formation energy. The Fermi level is located at above the bottom of the conduction band and a typical n-type metallic behavior occurs as a result of the oxygen vacancy appeared in ( Mo + C ) doped TiO 2.

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Strain-induced semimetal-to-semiconductor transition and indirect-to-direct band gap transition in monolayer 1T-TiS2

RSC Advances ◽

10.1039/c5ra16877e ◽

2015 ◽

Vol 5 (102) ◽

pp. 83876-83879 ◽

Cited By ~ 23

Author(s):

Chengyong Xu ◽

Paul A. Brown ◽

Kevin L. Shuford

Keyword(s):

Band Gap ◽

Electronic Properties ◽

Plane Strain ◽

Material Properties ◽

First Principles ◽

Tensile Strain ◽

First Principles Calculations ◽

Direct Band Gap ◽

Direct Band ◽

Uniform Plane

We have investigated the effect of uniform plane strain on the electronic properties of monolayer 1T-TiS2using first-principles calculations. With the appropriate tensile strain, the material properties can be transformed from a semimetal to a direct band gap semiconductor.

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Calculation of Conduction Band Structure Tensile Strained Ge1-xSnx Alloys for Achieving Direct Band Gap Materials

Laser & Optoelectronics Progress ◽

10.3788/lop57.091602 ◽

2020 ◽

Vol 57 (9) ◽

pp. 091602

Author(s):

孙钦钦 Sun Qinqin ◽

黄诗浩 Huang Shihao

Keyword(s):

Band Structure ◽

Band Gap ◽

Conduction Band ◽

Direct Band Gap ◽

Direct Band

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Band structure, phonon spectrum, and thermoelectric properties of β-BiAs and β-BiSb monolayers

Journal of Materials Chemistry C ◽

10.1039/c9tc04842a ◽

2020 ◽

Vol 8 (2) ◽

pp. 581-590 ◽

Cited By ~ 1

Author(s):

C. Y. Wu ◽

L. Sun ◽

J. C. Han ◽

H. R. Gong

Keyword(s):

Band Structure ◽

Thermoelectric Properties ◽

First Principles ◽

Phonon Spectrum ◽

Transport Theory ◽

First Principles Calculation ◽

Boltzmann Transport ◽

Band Structures ◽

Boltzmann Transport Theory ◽

Phonon Spectra

First-principles calculation and Boltzmann transport theory have been combined to comparatively investigate the band structures, phonon spectra, and thermoelectric properties of both β-BiSb and β-BiAs monolayers.

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Transition from indirect to direct band gap in SiC monolayer by chemical functionalization: A first principles study

Superlattices and Microstructures ◽

10.1016/j.spmi.2019.106320 ◽

2020 ◽

Vol 137 ◽

pp. 106320 ◽

Cited By ~ 6

Author(s):

D.M. Hoat ◽

Mosayeb Naseri ◽

Nguyen N. Hieu ◽

R. Ponce-Pérez ◽

J.F. Rivas-Silva ◽

...

Keyword(s):

Band Gap ◽

First Principles ◽

Chemical Functionalization ◽

Direct Band Gap ◽

First Principles Study ◽

Direct Band

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A first-principles study of the effects of different Al constituents on Ga1−xAlxN nanowires

International Journal of Modern Physics B ◽

10.1142/s0217979216502179 ◽

2016 ◽

Vol 30 (30) ◽

pp. 1650217 ◽

Cited By ~ 2

Author(s):

Sihao Xia ◽

Lei Liu ◽

Yike Kong ◽

Honggang Wang ◽

Meishan Wang

Keyword(s):

Optical Properties ◽

Band Structure ◽

Plane Wave ◽

First Principles ◽

Formation Energy ◽

High Energy ◽

Dielectric Constants ◽

Interesting Phenomenon ◽

Densities Of States ◽

Static Dielectric Constants

In order to investigate the influences of different Al constituents on Ga[Formula: see text]Al[Formula: see text]N nanowires, the formation energy, stability, band structure, densities of states and optical properties of Ga[Formula: see text]Al[Formula: see text]N nanowires with different Al constituents are calculated using first-principles plane-wave ultrasoft pseudopotential method. Results show that Ga[Formula: see text]Al[Formula: see text]N nanowires become more stable with increasing Al constituent. Bandgap of Ga[Formula: see text]Al[Formula: see text]N nanowires increases as the Al constituent increases but with a lower amplification compared with bulk Ga[Formula: see text]Al[Formula: see text]N. The peaks of static dielectric constants show a decreasing trend and move towards high-energy side as Al constituent increases. The absorption of Ga[Formula: see text]Al[Formula: see text]N nanowires shows an interesting phenomenon that it firstly increases and then decreases slightly as the Al constituent increases. Reflectivity of Ga[Formula: see text]Al[Formula: see text]N nanowires is much smaller than that of the bulk. The optical properties of Ga[Formula: see text]Al[Formula: see text]N nanowires show a blueshift effect as Al composition increases. According to these calculations, it is found that Ga[Formula: see text]Al[Formula: see text]N nanowires are appropriate to be applied into photoelectric detecting materials by adjusting the Al constituent of Ga[Formula: see text]Al[Formula: see text]N nanowires.

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Direct band gap narrowing and light-harvesting-potential in orthorhombic In-doped-AlFeO3 perovskite: A first principles study

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2018.03.388 ◽

2018 ◽

Vol 750 ◽

pp. 312-319 ◽

Cited By ~ 7

Author(s):

G. Sudha Priyanga ◽

Tiju Thomas

Keyword(s):

Band Gap ◽

First Principles ◽

Light Harvesting ◽

Direct Band Gap ◽

First Principles Study ◽

Direct Band ◽

Band Gap Narrowing

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First-principles exploration of oxygen vacancy impact on electronic and optical properties of ABO3−δ (A = La, Sr; B = Cr, Mn) perovskites

Physical Chemistry Chemical Physics ◽

10.1039/d0cp05445c ◽

2020 ◽

Vol 22 (46) ◽

pp. 27163-27172

Author(s):

Jongwoo Park ◽

Yu-Ning Wu ◽

Wissam A. Saidi ◽

Benjamin Chorpening ◽

Yuhua Duan

Keyword(s):

Optical Properties ◽

Electronic Structure ◽

Oxygen Vacancy ◽

First Principles ◽

Oxygen Vacancies ◽

Gas Sensing ◽

Optical Responses ◽

Sensing Applications ◽

Optical Gas Sensing ◽

The Impact

We explore via first-principles the impact of oxygen vacancies on the electronic structure and optical responses of ABO3−δ (A = La, Sr; B = Cr, Mn) perovskites, which provides a reference for optical gas sensing applications.

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