Molecular Dynamic Behavior of Lithium Atoms in a Flat Silicene Pore on a Copper Substrate

摘要

The processes of lithization/delithization in a flat slit-like pore formed from defective silicene sheets and located on a copper substrate are considered in a molecular dynamic (MD) simulation. Depending on the type of the defects (mono-, bi-, tri-, hexavacancies), such a pore can hold up to 67, 86, 60, and 23 lithium atoms during the entire MD calculation with the duration of up to 1 ns without being destroyed. As a result of the intercalation/deintercalation cycle, the structure of defective silicene changes, especially in the presence of tri- and hexavacancies. With the increase in the size of the defects, the mobility of the lithium atoms in the silicene pore also increases. The shape of the silicene sheets is not restored after delithization, and the volume of the space enclosed between them slightly changes. Effective use of silicene in lithium-ion batteries assumes that only mono- and bivacancies are present in its sheets.