Scientific Achievement
The role of vacancy defects in charge transfer and interfacial reaction processes were unveiled for anatase TiO2 nanoparticle surfaces using multimodal analysis with lithium bis(trifluoromethanesulfonyl)imde (Li-TFSI) as a probing molecule.
Significance and Impact
The oxygen vacancies at the anatase surface act as catalytic sites for TFSI- anion decomposition to form radical ions, revealing a role for surface defects on metal oxide-based electrodes. These results also emphasize the localized dependence of electrolyte stability as the origin of heterogeneous interphase formation.
Research Details
- HR-TEM and XRD analyses reveal that preferential LiTFSI dissociative adsorption occurs on a step edge along (100).
- AIMD simulations and 7Li NMR analysis indicates a preferential Li+ diffusion along the surface rather than inserting into the anatase TiO2.
- Multimodal spectroscopic and AIMD computational analysis demonstrates that CF3 bond cleavage in TFSI is activated by surface oxygen vacancies, leading to the formation of OCF–based radical ions.