Etude par dynamique moléculaire ab initio de la diffusion de proton au sein de matériaux poreux à base de TiO2 (structure du type lepidocrocite)

Master's internship, AAP 2017

Team: Laboratoire PHENIX

Project leader : Mathieu Salanne

Abstract :

By modifying the synthesis conditions of TiO₂ anatase nanoparticles, a lamelar compound was isolated, that has a lepidocrocite-type structure. The atomic-scale structure was characterized by combining the experimental determination of the pair distribution function with DFT calculations (Ma et al., Chem. Mater., 29, 8313, 2017). These materials have interesting properties for battery applications, since they allow to intercalate reversibly Li⁺, Mg²⁺ and Al³⁺ ions. The presence of a water layer between two crystalline layers allows for a rapid transport of the ions. However, the eventual role of proton ions within this layer was not elucidated so far. In order to understand their diffusion mechanisms, we will perform ab initio molecular dynamics simulations. This method was chosen because it allows to perform chemical reactions while accounting for the finite temperature fluctuations of the solvent molecules.

Axes :

• Renewable energies
• Towards modeling at all scales

Collaborations :

• UMR PASTEUR (ENS/UPMC/CNRS), Rodolphe Vuilleumier