TiO2 anatase's bulk and (001) surface, structural and electronic properties: A DFT study on the importance of Hubbard and van der Waals contributions

Araujo-López, Eduard; Varilla, L. A. Alcalá; Seriani, Nicola; Montoya, Javier A.

doi:10.1016/j.susc.2016.07.003

Cited by 50 publications

(35 citation statements)

References 76 publications

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“… a) GGA+ U ( U eff = 4.2 eV); b) GGA; c) GGA; d) GGA+ U ( U eff = 4.2 eV); e) GGA; f) GGA+U ( U eff = 9.0 eV) …”

Section: Resultsmentioning

confidence: 99%

“…Onefold coordinated O (O 1c ) atoms, as indicated by thin orange solid line in Figure , contribute the vacancy states in the TiV and TiO 2 V_ver2 models. It is known that first‐principles calculations utilizing GGA usually underestimate

E_{normalg}

, even with a + U approach in the case of TiO 2 . Although it would therefore be meaningless to directly compare the calculated

E_{normalg}

with that observed experimentally, it is meaningful to compare the qualitative dependence of

E_{normalg}

on the vacancy between theory and experiment.…”

Section: Resultsmentioning

confidence: 99%

“…We set the plane‐wave cutoff energies of 30 and 250 Ry for the electronic pseudo‐wave functions and the pseudo charge density, respectively. Our calculations employed the DFT+ U approach with U eff = 4.2 eV, because it has been known that this U eff value reproduces structural properties of anatase, such as lattice parameters, interatomic distances, and bond angles, reported experimentally fairly well, although the calculated bandgap is corrected only in a modest way . We used the Γ point for Brillouin‐zone sampling.…”

Section: Methods Of Calculationmentioning

confidence: 99%

“…Our calculations employed the DFTþU approach with U eff ¼ 4.2 eV, because it has been known that this U eff value reproduces structural properties of anatase, such as lattice parameters, interatomic distances, and bond angles, reported experimentally fairly well, although the calculated bandgap is corrected only in a modest way. [24,25] We used the Γ point for Brillouin-zone sampling. As valence electrons, we included the 3d, 4s, and 4p electrons of Ti (four valence electrons), the 2s and 2p electrons of O (six valence electrons), and the 1s electron of H (one valence electron).…”

Section: Methods Of Calculationmentioning

confidence: 99%

“…It is known that first-principles calculations utilizing GGA usually underestimate E g , even with a þU approach in the case of TiO 2 . [24,25] Although it would therefore be meaningless to directly compare the calculated E g with that observed experimentally, it is meaningful to compare the qualitative dependence of E g on the vacancy between theory and experiment. Photochemical and photoelectrical experiments [6] have shown that the values of E g for TNSs are larger than that of bulk anatase because of quantum size effects induced by the extreme two-dimensional structure of the TNSs.…”

Section: Electronic Density Of Statesmentioning

confidence: 99%

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Electronic Structure of Titania Nanosheets With Vacancies Based on Nonadiabatic Quantum Molecular Dynamics Simulations

Uchida

Hara

Funatsu

et al. 2018

Physica Status Solidi (b)

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Titania nanosheets (TNSs) are expected to be applied to new, flexible, and high‐performance photocatalytic materials utilizing their two‐dimensional structure. Although it has been indicated that an experimentally synthesized TNS has more than a few Ti vacancies, the effects of these vacancies on the photocatalytic activity of a TNS have not yet been elucidated. Here, we present the results of first‐principles molecular dynamics simulations for various TNS structural models, both with and without a Ti vacancy. The calculated electronic density of states and bandgap energies Enormalg of the TNSs are compared with those of bulk anatase. Provided that proper models are utilized, we confirm that TNSs have larger bandgap energies than anatase, as is observed experimentally, regardless of the existence of a Ti vacancy. Non‐adiabatic molecular dynamics simulations show that a Ti vacancy induces a spatial separation of the photogenerated electron and hole, and increases their recombination time. Accordingly, there are large differences in photocatalytic activity among the structural models. We therefore conclude that it is crucial to consider the effects of Ti vacancies in order to evaluate the photochemical properties of TNSs precisely.

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“… a) GGA+ U ( U eff = 4.2 eV); b) GGA; c) GGA; d) GGA+ U ( U eff = 4.2 eV); e) GGA; f) GGA+U ( U eff = 9.0 eV) …”

Section: Resultsmentioning

confidence: 99%

E_{normalg}

, even with a + U approach in the case of TiO 2 . Although it would therefore be meaningless to directly compare the calculated

E_{normalg}

with that observed experimentally, it is meaningful to compare the qualitative dependence of

E_{normalg}

on the vacancy between theory and experiment.…”

Section: Resultsmentioning

confidence: 99%

Section: Methods Of Calculationmentioning

confidence: 99%

Section: Methods Of Calculationmentioning

confidence: 99%

Section: Electronic Density Of Statesmentioning

confidence: 99%

See 3 more Smart Citations

Electronic Structure of Titania Nanosheets With Vacancies Based on Nonadiabatic Quantum Molecular Dynamics Simulations

Uchida

Hara

Funatsu

et al. 2018

Physica Status Solidi (b)

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A systematic DFT study of structure and electronic properties of titanium dioxide

Marzouk,

Papavasileiou,

Peristeras

et al. 2024

J Comput Chem

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DFT functionals are of paramount importance for an accurate electronic and structural description of transition metal systems. In this work, a systematic analysis using some well‐known and commonly used DFT functionals is performed. A comparison of the structural and energetic parameters calculated with the available experimental data is made in order to find the adequate functional for an accurate description of the TiO2 bulk and surface of both anatase and rutile structures. In the absence of experimental data on the surface energy, the theoretical predictions obtained using the high‐accuracy HSE06 functional were used as a reference to compare against the surface energy values calculated with the other DFT functionals. A clear improvement in the electronic description of both anatase and rutile was observed by introducing the Hubbard U correction term to PBE, PW91, and OptPBE functionals. The OptPBE‐U4 functional was found to offer a good compromise between accurately describing the structural and electronic properties of titania.

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Single Atom Ag Bonding Between PF3T Nanocluster and TiO₂ Leads the Ultra‐Stable Visible‐Light‐Driven Photocatalytic H₂ Production

Kao,

Teng,

Lin

et al. 2024

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Atomic Ag cluster bonding is employed to reinforce the interface between PF3T nano‐cluster and TiO2 nanoparticle. With an optimized Ag loading (Ag/TiO2 = 0.5 wt%), the Ag atoms will uniformly disperse on TiO2 thus generating a high density of intermediate states in the band gap to form the electron channel between the terthiophene group of PF3T and the TiO2 in the hybrid composite (denoted as T@Ag05‐P). The former expands the photon absorption band width and the latter facilitates the core‐hole splitting by injecting the photon excited electron (from the excitons in PF3T) into the conduction band (CB) of TiO2. These characteristics enable the high efficiency of H2 production to 16 580 µmol h−1 g−1 and photocatalysis stability without degradation under visible light exposure for 96 h. Compared to that of hybrid material without Ag bonding (TiO2@PF3T), the H2 production yield and stability are improved by 4.1 and 18.2‐fold which shows the best performance among existing materials in similar component combination and interfacial reinforcement. The unique bonding method offers a new prospect to accelerate the development of photocatalytic hydrogen production technologies.

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TiO2 anatase's bulk and (001) surface, structural and electronic properties: A DFT study on the importance of Hubbard and van der Waals contributions

Cited by 50 publications

References 76 publications

Electronic Structure of Titania Nanosheets With Vacancies Based on Nonadiabatic Quantum Molecular Dynamics Simulations

Electronic Structure of Titania Nanosheets With Vacancies Based on Nonadiabatic Quantum Molecular Dynamics Simulations

A systematic DFT study of structure and electronic properties of titanium dioxide

Single Atom Ag Bonding Between PF3T Nanocluster and TiO₂ Leads the Ultra‐Stable Visible‐Light‐Driven Photocatalytic H₂ Production

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TiO2 anatase's bulk and (001) surface, structural and electronic properties: A DFT study on the importance of Hubbard and van der Waals contributions

Cited by 50 publications

References 76 publications

Electronic Structure of Titania Nanosheets With Vacancies Based on Nonadiabatic Quantum Molecular Dynamics Simulations

Electronic Structure of Titania Nanosheets With Vacancies Based on Nonadiabatic Quantum Molecular Dynamics Simulations

A systematic DFT study of structure and electronic properties of titanium dioxide

Single Atom Ag Bonding Between PF3T Nanocluster and TiO2 Leads the Ultra‐Stable Visible‐Light‐Driven Photocatalytic H2 Production

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About

Single Atom Ag Bonding Between PF3T Nanocluster and TiO₂ Leads the Ultra‐Stable Visible‐Light‐Driven Photocatalytic H₂ Production