Orientation effects in morphology and electronic properties of anatase TiO2 one-dimensional nanostructures. II. Nanotubes
2014 (English)In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 16, no 20, 9490-9498 p.Article in journal (Refereed) Published
In the first part [D. B. Migas et al., Phys. Chem. Chem. Phys., 2014, DOI: 10.1039/C3CP54988G] by means of ab initio calculations we have analyzed and discussed anisotropy effects on electronic properties of 001 -, 100 - and 110 - oriented anatase TiO2 nanowires. In this part we present results indicating crucial changes in morphology of anatase TiO2 nanotubes originating from TiO2 nanowires by making a hole along the wire axis. The critical wall thickness has been found to exist for the nanotubes with 001 and 110 axes: at smaller thickness their shape can be rounded, squeezed, viewed as conglomerates of nanocrystals and even represented as cylindrical and `single-walled'- like structures formed without rolling up a thin titania layer into a nanotube. In general, band dispersion near the gap region of TiO2 nanotubes is close to the one of TiO2 nanowires with the same orientation. We have also revealed that optimization of the unit cell parameter along the wire axis and consideration of quantum confinement and surface state effects are important to provide an interpretation of band-gap variation with respect to wall thickness in TiO2 nanotubes.
Place, publisher, year, edition, pages
2014. Vol. 16, no 20, 9490-9498 p.
Physical Sciences Chemical Sciences
IdentifiersURN: urn:nbn:se:uu:diva-227588DOI: 10.1039/c3cp54906bISI: 000335818600032OAI: oai:DiVA.org:uu-227588DiVA: diva2:730407