Combination of silicene and boronene as a potential anode material for high-performance lithium-ion batteries: Insights from first principles

Abstract

Material design is essential for the development and preparation of new materials. In this paper, a new two-dimensional heterostructure material (B@Si) consisting of boronene and silicene is designed and used as an anode material for lithium-ion batteries in order to improve the performance of lithium-ion batteries, and the structural properties, stability, electronic properties, and performance as an anode material for lithium-ion batteries are systematically investigated by first-principle calculations of the B@Si heterostructure. The results show that the B@Si heterostructure is energetically, thermodynamically and dynamically stable, and although the Dirac cone in the energy band structure of silicene disappears after the formation of the heterojunction, the overall electrical conductivity of the material improves considerably and the electron transport rate is faster. Due to the synergistic effect, Li has more stable adsorption sites and lower diffusion barriers than boronene and silicene in the B@Si heterostructure, higher theoretical specific capacity (1208 mAhg−1), and stronger mechanical properties (C11 = 296.6 N/m, C22 = 142.8 N/m). The volume expansion in the fully lithiated state is also only 8 %. These advantages indicate that B@Si heterostructures are good potential anode materials for high-performance Li-ion batteries.

Keywords

• Heterostructure
• Lithium-ion battery
• 2D material