First-Principles Study on the Structural and Electronic Properties of N Atoms Doped-Rutile TiO2of Oxygen Vacancies

For the propose of considering the actual situation of electronic neutral, a simulation has been down on the basis of choosing the position of dual N and researching the oxygen vacancy. It is found that the reason why crystal material gets smaller is due to the emergence of impurity levels. By introducing the oxygen vacancy to the structure, the results show that while the oxygen vacancy is near the two nitrogen atoms which have a back to back position, its energy gets the lowest level and its structure gets the most stable state. From its energy band structure and density, the author finds that the impurity elements do not affect the migration of Fermi level while the oxygen vacancy has been increased. Instead of that, the conduction band of metal atoms moves to the Fermi level and then forms the N-type semiconductor material, but the photocatalytic activity is not as good as the dual N-doping state.

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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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Structural and Electronic Properties of Oxygen Vacancies in Monoclinic HfO2

MRS Proceedings ◽

10.1557/proc-0996-h01-08 ◽

2007 ◽

Vol 996 ◽

Author(s):

Peter Broqvist ◽

Alfredo Pasquarello

Keyword(s):

Oxygen Vacancy ◽

Optical Absorption ◽

Total Energy ◽

Band Gap ◽

Electronic Properties ◽

Density Functional ◽

Oxygen Vacancies ◽

Structural And Electronic Properties ◽

Defect Levels ◽

Hybrid Density Functional

AbstractWe study structural and electronic properties of the oxygen vacancy in monoclinic HfO2 for five different charge states. We use a hybrid density functional to accurately reproduce the experimental band gap. To compare with measured defect levels, we determine total-energy differences appropriate to the considered experiments. Our results show that the oxygen vacancy can consistently account for the defect levels observed in optical absorption, direct electron injection, and trap-assisted conduction experiments.

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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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First-principles study of structural and electronic properties ofBaTiO3(001)oxygen-vacancy surfaces

Physical Review B ◽

10.1103/physrevb.72.075406 ◽

2005 ◽

Vol 72 (7) ◽

Cited By ~ 37

Author(s):

Meng-Qiu Cai ◽

Yong-Jun Zhang ◽

Zhen Yin ◽

Ming-Sheng Zhang

Keyword(s):

Oxygen Vacancy ◽

Electronic Properties ◽

First Principles ◽

First Principles Study ◽

Structural And Electronic Properties

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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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STRUCTURAL AND ELECTRONIC EVOLUTION FROM SiC SHEET TO SILICENE

International Journal of Modern Physics B ◽

10.1142/s0217979213501889 ◽

2013 ◽

Vol 27 (32) ◽

pp. 1350188 ◽

Cited By ~ 2

Author(s):

G. LIU ◽

M. S. WU ◽

C. Y. OUYANG ◽

B. XU

Keyword(s):

Density Functional Theory ◽

Fermi Level ◽

Density Of States ◽

First Principles ◽

Density Functional ◽

Band Gaps ◽

Functional Theory ◽

Orbital Contribution ◽

Structural And Electronic Properties ◽

Substitution Ratio

The evolution of the structural and electronic properties from SiC sheet to silicene is studied by using first-principles density functional theory. It is found that the planar configurations of the Si – C monolayer systems are basically kept except for the increase of the buckling of the planar structure when the substitution ratio of Si increases. Band gaps of the Si – C monolayer system decrease gradually when the substitution ratio of Si atoms ranges from 0% to 100%. The energy and type of the band gaps are closely related with the substitution ratio of Si atoms and the Si – C order. Further analysis of density of states reveals the orbital contribution of Si and C atoms near the Fermi level. The discussion of the electronic evolution from SiC sheet to silicene would widen the application of the Si – C monolayer systems in the optoelectronic field in the future nanotechnology.

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ENHANCEMENT OF GRAPHENE BINDING ENERGY BY Ti 1ML INTERCALATION BETWEEN GRAPHENE AND METAL SURFACES

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194512006034 ◽

2012 ◽

Vol 11 ◽

pp. 139-144

Author(s):

TOMOAKI KANEKO ◽

HIROSHI IMAMURA

Keyword(s):

Binding Energy ◽

Total Energy ◽

Electronic Properties ◽

Metal Surface ◽

First Principles ◽

Metal Surfaces ◽

Energy Calculations ◽

Metal Atoms ◽

Structural And Electronic Properties

We theoretically investigate the effects of intercalation of a thin Ti layer between graphene (Gr) and metal surface ( Au , Ag , Al , Pt , and Pd ) on structural and electronic properties by using the first-principles total energy calculations. We find that the strongest binding energy is realized when 1 monolayer (ML) of Ti is intercalated between Gr and a metal surface independent of the metal atoms, which is 0.08-0.15 eV larger than that for Gr absorbed on a Ti (0001) surface. As the number of Ti layers increases, the binding energy monotonically decreases and converges to that for Gr adsorbed onto the Ti surface. We show that the origin of the enhancement of binding energy can be classified into two classes by considering the affinity of Ti for the metal surfaces.

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First Principles Calculations to Describe Zirconia Pseudopolymorphs

MRS Proceedings ◽

10.1557/proc-492-79 ◽

1997 ◽

Vol 492 ◽

Cited By ~ 1

Author(s):

G. Jomard ◽

T. Petit ◽

L. Magaud ◽

A. Pasturel

Keyword(s):

First Principles ◽

Density Functional ◽

Oxygen Vacancies ◽

Local Density ◽

First Principles Calculations ◽

Generalized Gradient ◽

Pseudopotential Theory ◽

Structural And Electronic Properties ◽

Gradient Corrections ◽

Made In

ABSTRACTThe structural and electronic properties of four different structures of zirconia (ZrO2) are studied using ab initio total energy calculations. The calculations are made in the framework of density functional (DFT) and pseudopotential theory. We compare results given within the LDA (Local Density Approximation) and including Generalized Gradient Corrections (GGCs) in the Perdew Wang and Perdew Becke formalisms. We present results for pure and defective zirconia (oxygen vacancies and Zr substitution by Fe) showing the effects of such point defects on tne relative structural stabilities of the different pseudopolymorphs.

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A DFT Study of B, N and BN Doped Graphene

MRS Proceedings ◽

10.1557/opl.2014.538 ◽

2014 ◽

Vol 1701 ◽

Cited By ~ 1

Author(s):

Pooja Rani ◽

V. K. Jindal

Keyword(s):

Fermi Level ◽

Band Gap ◽

Electronic Properties ◽

Density Functional ◽

Functional Study ◽

Co Doping ◽

Substitutional Doping ◽

Structural And Electronic Properties ◽

N Doping ◽

Doped Graphene

ABSTRACTWe have made a density functional study of the structural and electronic properties of B or N (individual) doped and BN co-doped graphene. The effect of doping has been studied by incorporating the doping concentration amount varying from 2% (one atom of the dopant in 50 host atoms) to 12 % atomic concentration in case of individual doping and from 4% (2 atoms of the dopant in 50 host atoms) to 24 % in case of co-doping, at the same time, altering different doping sites for the same concentration of substitutional doping. We made use of VASP (Vienna Ab-Initio Simulation Package) software based on density functional theory to perform all calculations. While the resulting geometries do not show much of distortion on doping, the electronic properties show a transition from semimetal to semiconductor with increasing number of dopants. The study shows that the BN doping introduces the band gap at the Fermi level unlike individual B and N doping which causes the shifting of Fermi level above or below the Dirac point. It is observed that not only concentration but position of B and N atoms in the hetero-structure also affects the value of band gap introduced.

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