Dual roles of [NCN]2- on anatase TiO2: A fully occupied molecular gap state for direct charge injection into the conduction band and an interfacial mediator for the covalent formation of heterostructured g-C3N4/a-TiO2 nanocomposite

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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Size effect on the conduction band orbital character of anatase TiO2 nanocrystals

Applied Physics Letters ◽

10.1063/1.3657147 ◽

2011 ◽

Vol 99 (18) ◽

pp. 183101 ◽

Cited By ~ 25

Author(s):

L. Vayssieres ◽

C. Persson ◽

J.-H. Guo

Keyword(s):

Size Effect ◽

Conduction Band ◽

Anatase Tio2 ◽

Tio2 Nanocrystals ◽

Orbital Character

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A First-Principles Study on Electronic Properties of Ce/N Codoped Anatase TiO2

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.936.529 ◽

2014 ◽

Vol 936 ◽

pp. 529-533 ◽

Cited By ~ 1

Author(s):

Si Yu Yang ◽

Lan Fang Yao ◽

Hao Chen

Keyword(s):

Band Gap ◽

Valence Band ◽

Conduction Band ◽

First Principles ◽

Function Theory ◽

Pure Tio2 ◽

Anatase Tio2 ◽

Photoelectrochemical Activity ◽

Co Doping ◽

N Doping

Density function theory is performed in order to investigate the effect of Ce/N co-doping on geometry structure, electronic and optical properties of anatase TiO2. Comparing the energy band and density of states of pure TiO2 and Ce/N doped anatase TiO2. We can conclude that, the valence band of pure TiO2 is main composed of O 2p states and the conduction is mainly composed of Ti 3d states. For N-doped TiO2, the topmost part of the valence band is mainly occupied by N 2p states which is higher than that of the O 2p states which can narrowed the band gap. Ce doping will introduce 4f states which is involved in the conduction band. These may lead the conduction band move down. As for Ce and N co-doped, the top of the valence band is mainly occupied by an admixture N 2p, O 2p and the bottom of the conduction band is predominantly occupied by an admixture of Ce 4f ,Ti 3d. The strong interaction between the dopants and the ions lead the band gap get narrower. We predict that Ce+N doping is one of the best choices for enhancing the photoelectrochemical activity of TiO2.

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Magnetic Properties of xCeO2â€¢(50 âˆ’ x) PbOâ€¢50B2O3 Glasses and Glass Ceramics

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v13i1.6785 ◽

2017 ◽

Vol 13 (1) ◽

pp. 4486-4494 ◽

Cited By ~ 1

Author(s):

G.El Damrawi ◽

F. Gharghar

Keyword(s):

Magnetic Properties ◽

Large Scale ◽

Glass Ceramics ◽

Magnetic Behavior ◽

Crystal Formation ◽

Dual Roles ◽

Effective Agent ◽

Ordered Structures ◽

Essential Change

Cerium oxide in borate glasses of composition xCeO2Â·(50 âˆ’ x)PbOÂ·50B2O3 plays an important role in changing both microstructure and magnetic behaviors of the system. The structural role of CeO2 as an effective agent for cluster and crystal formation in borate network is clearly evidenced by XRD technique. Both structure and size of well-formed cerium separated clusters have an effective influence on the structural properties. The cluster aggregations are documented to be found in different range ordered structures, intermediate and long range orders are the most structures in which cerium phases are involved. The nano-sized crystallized cerium species in lead borate phase are evidenced to have magnetic behavior. The criteria of building new specific borate phase enriched with cerium as ferrimagnetism has been found to keep the magnetization in large scale even at extremely high temperature. Treating the glass thermally or exposing it to an effective dose of ionized radiation is evidenced to have an essential change in magnetic properties. Thermal heat treatment for some of investigated materials is observed to play dual roles in the glass matrix. It can not only enhance alignment processes of the magnetic moment but also increases the capacity of the crystallite species in the magnetic phases. On the other hand, reverse processes are remarked under the effect of irradiation. The magnetization was found to be lowered, since several types of the trap centers which are regarded as defective states can be produced by effect of ionized radiation.

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