Theoretical study of alkali metals (Li, Na, K) intercalation in the H2Ti3O7(1 0 0) surface

Abstract

The H2Ti3O7 system has potential to be applied as a Li/Na/K-ion battery anode material. It is relevant to theoretically study the (1 0 0) nanosheet of this material since there are no studies regarding intercalation of Li/ Na/K in it. Density Functional Theory calculations with the Hubbard methodology (DFT + U) were conducted in order to find and test several intercalation sites for the three different metals, finding stability and high voltages in all of them. Moreover, the electronic density of states confirms the stability of the systems and charge transfer studies were performed to compare the electron transfer between the most stable sites of each intercalated metal and the surface. Nudged Elastic Band (NEB) calculations were performed, finding lower barriers of 0.54 eV and 0.41 eV for Li and Na diffusion. This study shows that this material is promising and can be a guide for future works.