A review on the effects of TiO2 surface point defects on CO2 photoreduction with H2O

AbstractThe fundamental interactions involved in the bonding of atoms and molecules to metal oxides are discussed. Surface defects play a major role in many of those interactions. Both acid/base and oxidation/reduction reactions occur at metal-oxide surfaces, with the latter dominating at point defect sites. The reaction of metals with oxide surfaces is governed largely by the relative heats of formation of the respective oxides, although surface point defects also play an important role. Preliminary studies of ceramic/ceramic interfaces indicate that interfacial interactions are much weaker than for metal/ceramic interfaces.

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STRUCTURAL AND ELECTRONIC PROPERTIES OF c-BN(110) SURFACE AND SURFACE POINT DEFECTS

International Journal of Modern Physics C ◽

10.1142/s0129183106009308 ◽

2006 ◽

Vol 17 (06) ◽

pp. 795-803 ◽

Cited By ~ 5

Author(s):

HATICE KÖKTEN ◽

ŞAKIR ERKOÇ

Keyword(s):

Point Defects ◽

Cubic Boron Nitride ◽

Vacancy Formation ◽

Surface Point ◽

Hartree Fock ◽

Structural And Electronic Properties ◽

Structure Surface ◽

Surface Vacancy ◽

First Time ◽

Formation Energies

The surface structure, surface energy, and surface vacancy formation energy for B and N vacancy of the cubic boron nitride (c-BN)(110) surface have been investigated by performing Hartree-Fock and DFT calculations. Results are compared with available literature values. The vacancy formation energies [unrelaxed [Formula: see text] and relaxed (Ef)] are reported for the first time for c-BN(110).

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Subsurface diffusion in crystals and effect of surface permeability on the atomic step motion

Scientific Reports ◽

10.1038/s41598-019-49681-1 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 1

Author(s):

Sergey Kosolobov

Keyword(s):

Point Defects ◽

Atomic Step ◽

Surface Point ◽

Atomic Steps ◽

Sources And Sinks ◽

Step Rate ◽

Step Motion ◽

Surface Permeability ◽

Diffusive Layer ◽

Effect Of Surface

Abstract A new theoretical approach to characterize the diffusion of both surface and bulk point defects in crystals is presented. In our model, atomic steps are considered as sources and sinks not only for adatoms and advacancies but also for self-interstitials and bulk vacancies, providing a new mechanism for bulk point defect generation and annihilation. It is shown that the creation and annihilation of self-interstitials and vacancies occur at atomic steps and can be described by introducing a diffusive layer of the bulk point defects adsorbed just below the surface. The atomic step rate of advance is studied taking into account finite permeability of the surface for bulk and surface point defects. The surface permeability results in the appearance of the dependence of the total step rate of advance not only on the supersaturation in vapor phase but also on the supersaturation of point defects in the bulk.

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