Origin of the Enhanced Visible-Light Absorption in N-Doped Bulk Anatase TiO 2 from First-Principles Calculations

Handle URI:
http://hdl.handle.net/10754/599118
Title:
Origin of the Enhanced Visible-Light Absorption in N-Doped Bulk Anatase TiO 2 from First-Principles Calculations
Authors:
Harb, Moussab ( 0000-0001-5540-9792 ) ; Sautet, P.; Raybaud, P.
Abstract:
Extension of the absorption properties of TiO2 photocatalytic materials to the visible part of the solar spectrum is of major importance for energy and cleaning up applications. We carry out a systematic study of the N-doped anatase TiO2 material using spin-polarized density functional theory (DFT) and the range-separated hybrid HSE06 functional. The thermodynamic stability of competitive N-doped TiO2 structural configurations is studied as a function of the oxygen chemical potential and of various chemical doping agents: N2, (N2 + H2), NH3, N2H4. We show that the diamagnetic TiO (2-3x)N2x system corresponding to a separated substitutional N species (with 2-4% N impurities) and formation of one-half concentration of O vacancies (1-2 atom %) is an optimal configuration thermodynamically favored by NH3, N2H4, and (N2 + H2) chemical doping agents presenting a dual nitrating-reducing character. The simulated UV-vis absorption spectra using the perturbation theory (DFPT) approach demonstrates unambiguously that the diamagnetic TiO(2-3x)N2x system exhibits the enhanced optical absorption in N-doped TiO2 under visible-light irradiation. Electronic analysis further reveals a band gap narrowing of 0.6 eV induced by delocalized impurity states located at the top of the valence band of TiO 2. A fruitful comparison with experimental data is furnished. © 2011 American Chemical Society.
Citation:
Harb M, Sautet P, Raybaud P (2011) Origin of the Enhanced Visible-Light Absorption in N-Doped Bulk Anatase TiO 2 from First-Principles Calculations . The Journal of Physical Chemistry C 115: 19394–19404. Available: http://dx.doi.org/10.1021/jp204059q.
Publisher:
American Chemical Society (ACS)
Journal:
The Journal of Physical Chemistry C
KAUST Grant Number:
UK-C0017
Issue Date:
6-Oct-2011
DOI:
10.1021/jp204059q
Type:
Article
ISSN:
1932-7447; 1932-7455
Sponsors:
This work was supported by Award No. UK-C0017, made by King Abdullah University of Science and Technology (KAUST). The authors thank E. Puzenat (IRCELYON) for fruitful discussion.
Appears in Collections:
Publications Acknowledging KAUST Support

Full metadata record

DC FieldValue Language
dc.contributor.authorHarb, Moussaben
dc.contributor.authorSautet, P.en
dc.contributor.authorRaybaud, P.en
dc.date.accessioned2016-02-25T13:53:12Zen
dc.date.available2016-02-25T13:53:12Zen
dc.date.issued2011-10-06en
dc.identifier.citationHarb M, Sautet P, Raybaud P (2011) Origin of the Enhanced Visible-Light Absorption in N-Doped Bulk Anatase TiO 2 from First-Principles Calculations . The Journal of Physical Chemistry C 115: 19394–19404. Available: http://dx.doi.org/10.1021/jp204059q.en
dc.identifier.issn1932-7447en
dc.identifier.issn1932-7455en
dc.identifier.doi10.1021/jp204059qen
dc.identifier.urihttp://hdl.handle.net/10754/599118en
dc.description.abstractExtension of the absorption properties of TiO2 photocatalytic materials to the visible part of the solar spectrum is of major importance for energy and cleaning up applications. We carry out a systematic study of the N-doped anatase TiO2 material using spin-polarized density functional theory (DFT) and the range-separated hybrid HSE06 functional. The thermodynamic stability of competitive N-doped TiO2 structural configurations is studied as a function of the oxygen chemical potential and of various chemical doping agents: N2, (N2 + H2), NH3, N2H4. We show that the diamagnetic TiO (2-3x)N2x system corresponding to a separated substitutional N species (with 2-4% N impurities) and formation of one-half concentration of O vacancies (1-2 atom %) is an optimal configuration thermodynamically favored by NH3, N2H4, and (N2 + H2) chemical doping agents presenting a dual nitrating-reducing character. The simulated UV-vis absorption spectra using the perturbation theory (DFPT) approach demonstrates unambiguously that the diamagnetic TiO(2-3x)N2x system exhibits the enhanced optical absorption in N-doped TiO2 under visible-light irradiation. Electronic analysis further reveals a band gap narrowing of 0.6 eV induced by delocalized impurity states located at the top of the valence band of TiO 2. A fruitful comparison with experimental data is furnished. © 2011 American Chemical Society.en
dc.description.sponsorshipThis work was supported by Award No. UK-C0017, made by King Abdullah University of Science and Technology (KAUST). The authors thank E. Puzenat (IRCELYON) for fruitful discussion.en
dc.publisherAmerican Chemical Society (ACS)en
dc.titleOrigin of the Enhanced Visible-Light Absorption in N-Doped Bulk Anatase TiO 2 from First-Principles Calculationsen
dc.typeArticleen
dc.identifier.journalThe Journal of Physical Chemistry Cen
dc.contributor.institutionIFP Energies nouvelles, Rueil-Malmaison, Franceen
dc.contributor.institutionUniversite de Lyon, Lyon, Franceen
kaust.grant.numberUK-C0017en
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