Role of Quantum-Confinement in Anatase Nanosheets
Abstract
Despite most of the applications of anatase nanostructures rely on photoexcited charge processes, yet profound theoretical understanding of fundamental related properties is lacking. Here, by means of ab initio ground and excited-state calculations, we reveal, in an unambiguous way, the role of quantum confinement effect and of the surface orientation, on the electronic and optical properties of anatase nanosheets (NSs). The presence of bound excitons extremely localized along the (001) direction, whose existence has been recently proven also in anatase bulk, explains the different optical behavior found for the two orientations (001) and (101) when the NS thickness increases. We suggest also that the almost two-dimensional nature of these excitons can be related to the improved photoconversion efficiency observed when a high percentage of (001) facet is present in anatase nanocrystals.
Keywords
Cite
@article{arxiv.1808.06909,
title = {Role of Quantum-Confinement in Anatase Nanosheets},
author = {Daniele Varsano and Giacomo Giorgi and Koichi Yamashita and Maurizia Palummo},
journal= {arXiv preprint arXiv:1808.06909},
year = {2018}
}
Comments
This document is the Accepted Manuscript version of a Published Work that appeared in final form in J. Phys. Chem. Lett. copyright American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://dx.doi.org/10.1021/acs.jpclett.7b01717