Scanning Tunneling Microscopy and Molecular Dynamics Study of the Li₂TiO₃(001) Surface

Abstract

We have investigated the (001) surface structure of lithium titanate (Li2TiO3) using auger electron spectroscopy (AES), low-energy electron diffraction (LEED), and scanning tunneling microscopy (STM). Li2TiO3 is a potential fusion reactor blanket material. After annealing at 1200 K, LEED demonstrated that the Li2TiO3(001) surface was well ordered and not reconstructed. STM imaging showed that terraces are separated in height by about 0.3 nm suggesting a single termination layer. Moreover, hexagonal patterns with a periodicity of ∼0.4 nm are observed. On the basis of molecular dynamics (MD) simulations, these are interpreted as a dynamic arrangement of Li atoms.

Variation in surface energy and reduction drive of a metal oxide lithium-ion anode with stoichiometry: a DFT study of lithium titanate spinel surfaces

“…Under ambient conditions, Li 2 TiO 3 preferentially adopts the monoclinic b phase, which has been broadly studied due to potential applications as a microwave dielectric and as a possible tritium breeder in future fusion reactors. [37][38][39] The a phase, which we are interested in here, is metastable in bulk systems. This phase can be considered a disordered pseudorocksalt, consisting of a fcc oxide-ion lattice with all the octahedral sites occupied by lithium or titanium.…”

Microwave-Assisted Synthesis of High-Energy Faceted TiO2 Nanocrystals Derived from Exfoliated Porous Metatitanic Acid Nanosheets with Improved Photocatalytic and Photovoltaic Performance

“…The crystal structure of Li 2 TiO 3 could be represented as a cubic close packing of three different layers (Li 6 layers, O 6 layers, and Li 2 Ti 4 layers) in the c axis direction [37]. In the Li 2 Ti 4 layer, 1/3 of the 4e sites were occupied by lithium atoms and 2/3 by titanium atoms, so the formula for a well-ordered Li 2 TiO 3 could be written as Li(Li 1/3 Ti 2/3 )O 2 [37,38,39]. That is, the atomic fraction of titanium in the Li 6 layers and Li 2 Ti 4 layers was 75% and 25%, respectively [38].…”

Lithium Vapor Chemistry of Hyper-Stoichiometric Lithium Metatitanate Li2.12(2)TiO3+y

“…Given that activities in the pure substances equal to 1, equilibrium constants K in the Eqs. (4), ( 5), (11), and ( 12) are described by partial pressures of Li and O2, namely.…”