The nature of interfaces and charge trapping sites in photocatalytic mixed-phase TiO2 from first principles modeling

dc.contributor.authorGarcia, Juan C.
dc.contributor.authorNolan, Michael
dc.contributor.authorDeskins, N. Aaron
dc.contributor.funderScience Foundation Irelanden
dc.contributor.funderHigher Education Authorityen
dc.contributor.funderEuropean Commissionen
dc.contributor.funderSeventh Framework Programmeen
dc.contributor.funderPartnership for Advanced Computing in Europe AISBLen
dc.contributor.funderEuropean Cooperation in Science and Technologyen
dc.date.accessioned2017-12-20T15:30:58Z
dc.date.available2017-12-20T15:30:58Z
dc.date.issued2015-01-12
dc.date.updated2017-12-20T12:21:22Z
dc.description.abstractMixed phase rutile/anatase catalysts show increased reactivity compared with the pure phases alone. However, the mechanism causing this effect is not fully understood. The electronic properties of the interface and the relative energy of the electron in each phase play a key role in lowering the rate of recombination of electron hole pairs. Using density functional theory and the +U correction, we calculated the bands offsets between the phases taking into account the effect of the interface. Our model included several thousands atoms, and thus is a good representation of an interface between actual nanoparticles. We found rutile to have both higher conduction and valence band offsets than rutile, leading to an accumulation of electrons in the anatase phase accompanied by hole accumulation in the rutile phase. We also probed the electronic structure of our heterostructure and found a gap state caused by electrons localized in undercoordinated Ti atoms which were present within the interfacial region. Interfaces between bulk materials and between exposed surfaces both showed electron trapping at undercoordinated sites. These undercoordinated (typically four) atoms present localized electrons that could enable reduction reactions in the interfacial region, and could explain the increased reactivity of mixed-phase TiO2 photocatalyst materials.en
dc.description.sponsorshipScience Foundation Ireland and Higher Education Authority (Irish Centre for High End Computing); European Commission (FP7 Research Infrastructures Project PRACE-RI; European Cooperation in Science and Technology (COST Action CM1104 “Reducible Oxide Chemistry, Structure, and Functions.”)en
dc.description.statusPeer revieweden
dc.description.versionPublished Versionen
dc.format.mimetypeapplication/pdfen
dc.identifier.citationGarcia, J. C., Nolan, M. and Deskins, N. A. (2015) 'The nature of interfaces and charge trapping sites in photocatalytic mixed-phase TiO2 from first principles modeling', The Journal of Chemical Physics, 142(2), 024708 (10pp). doi: 10.1063/1.4905122en
dc.identifier.doi10.1063/1.4905122
dc.identifier.endpage024708-10en
dc.identifier.issn0021-9606
dc.identifier.journaltitleJournal of Chemical Physicsen
dc.identifier.startpage024708-1en
dc.identifier.urihttps://hdl.handle.net/10468/5203
dc.identifier.volume142en
dc.language.isoenen
dc.publisherAIP Publishingen
dc.relation.projectinfo:eu-repo/grantAgreement/SFI/SFI Starting Investigator Research Grant (SIRG)/09/SIRG/I1620/IE/EMOIN: Engineering Metal Oxide Interfaces For Renewable Energy Photocatalysis/en
dc.rights© 2015 AIP Publishing LLC. This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. The following article appeared in The Journal of Chemical Physics 2015 142:2 and may be found at http://aip.scitation.org/doi/abs/10.1063/1.4905122en
dc.subjectAb initio calculationsen
dc.subjectCatalysisen
dc.subjectCatalystsen
dc.subjectConduction bandsen
dc.subjectDensity functional theoryen
dc.subjectElectron trapsen
dc.subjectElectron-hole recombinationen
dc.subjectEnergy gapen
dc.subjectInterface statesen
dc.subjectNanoparticlesen
dc.subjectPhotochemistryen
dc.subjectReaction kinetics theoryen
dc.subjectReduction (chemical)en
dc.subjectInterface structureen
dc.subjectElectrostaticsen
dc.subjectValence bandsen
dc.subjectInterfacial propertiesen
dc.subjectSurface structureen
dc.titleThe nature of interfaces and charge trapping sites in photocatalytic mixed-phase TiO2 from first principles modelingen
dc.typeArticle (peer-reviewed)en
Files
Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
4467.pdf
Size:
4.14 MB
Format:
Adobe Portable Document Format
Description:
Published version
License bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
license.txt
Size:
2.71 KB
Format:
Item-specific license agreed upon to submission
Description: