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Tuning the Electronic Structure of Anatase Through Fluorination.

ABSTRACT: A highly fluorinated anatase lattice has been recently reported, providing a new class of materials whose general chemical formula is Ti(1-x)□(x)X(4x)O(2-4x) (X(-) = F(-) or OH(-)). To characterise the complex structural features of the material and the different F environments, we here apply a computational screening procedure. After deriving a polarisable force-field from DFT simulations, we screen in a step-wise fashion a large number of possible configurations differing in the positioning of the titanium vacancies (□) and of the fluorine atoms. At each step only 10% of the configurations are retained. At the end of the screening procedure, a configuration is selected and simulated using DFT-based molecular dynamics. This allows us to analyse the atomic structure of the material, which is strongly disordered, leading to a strong decrease (by 0.8 eV) of the band gap compared to conventional anatase.

SUBMITTER: Corradini D

PROVIDER: S-EPMC5387870 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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Tuning the Electronic Structure of Anatase Through Fluorination.

Corradini Dario D Dambournet Damien D Salanne Mathieu M

Scientific reports 20150626

A highly fluorinated anatase lattice has been recently reported, providing a new class of materials whose general chemical formula is Ti(1-x)□(x)X(4x)O(2-4x) (X(-) = F(-) or OH(-)). To characterise the complex structural features of the material and the different F environments, we here apply a computational screening procedure. After deriving a polarisable force-field from DFT simulations, we screen in a step-wise fashion a large number of possible configurations differing in the positioning of ...[more]

PMID: 26113411

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