Energetics of hydrogen/lithium complexes in silicon analyzed using the Maxwell construction

Abstract

We have studied hydrogen/lithium complexes in crystalline silicon using density-functional-theory methods and the ab initio random structure searching (AIRSS) method for predicting structures. A method based on the Maxwell construction and convex hull diagrams is introduced which gives a graphical representation of the relative stabilities of point defects in a crystal and enables visualization of the changes in stability when the chemical potentials are altered. We have used this approach to study lithium and hydrogen impurities in silicon, which models aspects of the anode material in the recently-suggested lithium-ion batteries. We show that hydrogen may play a role in these anodes, finding that hydrogen atoms bind to three-atom lithium clusters in silicon, forming stable {H,3Li} and {2H,3Li} complexes, while the {H,2Li} complex is almost stable.

(5 pages, 4 figures)

References in corpus (3)

• Ab initio Random Structure Searching
• High-pressure phases of silane
• An ab initio study of intrinsic defects in zirconolite

Cited by in corpus (4)

• Identifying the ground state structures of point defects in solids
• Single-Atom Scale Structural Selectivity in Te Nanowires Encapsulated inside Ultra-Narrow, Single-Walled Carbon Nanotubes
• Thermodynamically stable lithium silicides and germanides from density-functional theory calculations
• Lithiation of silicon via lithium Zintl-defect complexes