Silicon- and carbon-based anode materials: Quantum-chemical modeling

Abstract

With the aim of searching for promising anode materials for lithium-ion batteries, we performed quantum-chemical modeling of the structure, stability, and electronic properties of silicon-coated carbon nanotubes, silicon rods, and silicon carbide fibers by the density functional theory method including gradient correction and periodic boundary conditions. It has been demonstrated that nanotubes poorly hold silicon, whereas silicon firmly adheres to the SiC surface. Silicon rods are more favorable than clusters and have the stability close to that of the crystal. The band gap in the rods is close to zero. Silicon carbide can be transformed into a conductor by doping with nitrogen.