Intrinsic electronic defect states of anatase using density functional theory

Raghav, Abhishek; Hanindriyo, Adie Tri; Utimula, Keishu; Abbasnejad, Mohaddeseh; Panda, Emila

doi:10.1016/j.commatsci.2020.109925

Cited by 20 publications

(6 citation statements)

References 50 publications

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“…Thus, more positive CB and more negative VB were obtained in OVs and carbon-doped TiO 2 relative to undoped anatase TiO 2 , because OVs and carbon dopants are along with localized Ti 3d defect states below the CB, as well as localized C 2p states above the VB of undoped anatase TiO 2 , respectively. [69,70] Hence, the intermediate sub-bands reduce the actual bandgap and promote widespectrum light absorption. More specifically, carbon atoms do not simply exist in the form of interstitial atoms due to the diffraction peaks of OV/C-TT-N 2 , OV/C-TT-1K(N 2 ), OV/C-TT-1K(CO 2 ), and C-TiO 2 -1K are not shifted, therefore most of the carbon is exist as carbon layers, which is consistent with Raman analysis.…”

Section: Optical and Electrical Properties Determinationmentioning

confidence: 99%

Oxygen Vacancies Modified TiO₂/O‐Terminated Ti₃C₂ Composites: Unravelling the Dual Effects between Oxygen Vacancy and High‐Work‐Function Titanium Carbide

Zhou

Jiang

Wang

et al. 2023

Adv Funct Materials

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The rational design of Ti3C2Tx MXene‐derived TiO2‐based photocatalysts with broad light absorption and efficient charge separation has recently attracted considerable attention for antibiotic degradation. However, the complementary effects of each component, especially oxygen vacancies (OVs) and high work function O‐terminated Ti3C2 (O‐Ti3C2), in affecting light absorption and photocatalytic activity remain controversial. In this study, Ti3C2Tx‐derived TiO2/Ti3C2Tx photocatalysts are regulated by alkalization in the controlled KOH solution and calcination in different heating atmospheres to reveal the contribution of OVs, Ti3+, carbon species, and high work function titanium carbide. Carbon species and rich OVs co‐exist in TiO2/O‐Ti3C2 (OV/C‐TT‐1K(N2)) which exhibit superior photocatalytic performance in tetracycline hydrochloride degradation with a kinetic constant of 0.0217 min−1. Combined with experimental and DFT computational results, the broadened visible light response and desirable redox properties are caused by OVs and carbon dopants, as well as decreased Schottky barrier height and enhanced electronic conductivity caused by high work function O‐Ti3C2.

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Section: Optical and Electrical Properties Determinationmentioning

confidence: 99%

Oxygen Vacancies Modified TiO₂/O‐Terminated Ti₃C₂ Composites: Unravelling the Dual Effects between Oxygen Vacancy and High‐Work‐Function Titanium Carbide

Zhou

Jiang

Wang

et al. 2023

Adv Funct Materials

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“…This reaction is directly analogous to what has been proposed for iron by Wilson et al [3] At high temperatures, vacancy condensation was directly observed in transmission electron microscopy, [48] which may also play a role under the conditions in this work. Thermodynamic defect levels for the different dominating defects in anatase TiO 2 are available in the literature, [49,50] and more recent literature also discussed the differences obtained in previous calculations. [50] As dissolution occurs from the surface, special surface or subsurface defects as suggested from density functional theory calculations [51] may be crucial in the predominant dissolution channels.…”

Section: The Role Of Electron-hole Pair Formationmentioning

confidence: 99%

Photocorrosion of n‐ and p‐Type Semiconducting Oxide‐Covered Metals: Case Studies of Anodized Titanium and Copper

Wilson

Rooij

Jenewein

et al. 2022

Physica Status Solidi (a)

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“…Besides hybrid functional, the DFT + U method is commonly used to represent localization of orbitals. However, DFT + U introduces unreasonable lattice distortions when suboptimal U values are used [84][85][86]. Moreover, unlike DFT + U, hybrid functional treat delocalized and localized states on the same footing through the orbital dependence of the Hartree-Fock (HF) exchange.…”

Section: Introductionmentioning

confidence: 99%

Modified HSE06 functional applied to anatase TiO₂: influence of exchange fraction on the quasiparticle electronic structure and optical response

B¹,

Murali²,

Posselt³

et al. 2022

Electron. Struct.

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The influence of non-interacting Kohn-Sham Hamiltonian on the non-self consistent GW (G0W0) quasiparticle gap and Bethe-Salpeter-Equation(BSE) optical spectra of anatase TiO2 is systematically evaluated. G0W0 and BSE calculations are carried out starting with HSE06 (Heyd-Scuseria-Ernzerhof) type functionals containing 20, 25 and 30% exact Hartree-Fock exchange. The results are also compared against G0W0+BSE calculations starting from semi-local(PBE) functionals. Our results indicate that the G0W0 and BSE calculations of anatase TiO2 depend critically on the mean-field starting point, wherein its dependence is mainly introduced through the dielectric screening evaluated at the intermediate G0W0. We find that the band dispersion, density of states, and consequently the oscillator strengths of optical excitation and spatial localization of excitons are insensitive to the starting points while the quasiparticle gap, optical gap and exciton binding energies are strongly affected. G0W0 quasiparticle gap of anatase TiO2 computed over hybrid functional starting points is typically overestimated compared to measured values. However, by varying the amount of exact exchange, the dielectric screening can be tuned, and thus the quasiparticle gap. Exciton binding energy is shown to increase in proportion to the increase of the amount of exact exchange. A simple extrapolation of the calculated data leads to the exact match with the recently measured value with 13% of the exact exchange. Systematic analysis of G0W0+BSE calculation starting from screened hybrid functionals provided in this study forms a reference for all such future calculations of pristine anatase TiO2 and its derivatives.

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Intrinsic electronic defect states of anatase using density functional theory

Cited by 20 publications

References 50 publications

Oxygen Vacancies Modified TiO₂/O‐Terminated Ti₃C₂ Composites: Unravelling the Dual Effects between Oxygen Vacancy and High‐Work‐Function Titanium Carbide

Oxygen Vacancies Modified TiO₂/O‐Terminated Ti₃C₂ Composites: Unravelling the Dual Effects between Oxygen Vacancy and High‐Work‐Function Titanium Carbide

Photocorrosion of n‐ and p‐Type Semiconducting Oxide‐Covered Metals: Case Studies of Anodized Titanium and Copper

Modified HSE06 functional applied to anatase TiO₂: influence of exchange fraction on the quasiparticle electronic structure and optical response

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Intrinsic electronic defect states of anatase using density functional theory

Cited by 20 publications

References 50 publications

Oxygen Vacancies Modified TiO2/O‐Terminated Ti3C2 Composites: Unravelling the Dual Effects between Oxygen Vacancy and High‐Work‐Function Titanium Carbide

Oxygen Vacancies Modified TiO2/O‐Terminated Ti3C2 Composites: Unravelling the Dual Effects between Oxygen Vacancy and High‐Work‐Function Titanium Carbide

Photocorrosion of n‐ and p‐Type Semiconducting Oxide‐Covered Metals: Case Studies of Anodized Titanium and Copper

Modified HSE06 functional applied to anatase TiO2: influence of exchange fraction on the quasiparticle electronic structure and optical response

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Product

Resources

About

Oxygen Vacancies Modified TiO₂/O‐Terminated Ti₃C₂ Composites: Unravelling the Dual Effects between Oxygen Vacancy and High‐Work‐Function Titanium Carbide

Oxygen Vacancies Modified TiO₂/O‐Terminated Ti₃C₂ Composites: Unravelling the Dual Effects between Oxygen Vacancy and High‐Work‐Function Titanium Carbide

Modified HSE06 functional applied to anatase TiO₂: influence of exchange fraction on the quasiparticle electronic structure and optical response