Monolayer, bilayer, and heterostructure B2C16 as potential anode materials for lithium-ion batteries: A first-principles study

Abstract

With the swift progress in renewable energy technologies, there has been a significant increase in the worldwide need for advanced materials for lithium-ion batteries (LIBs). Through first-principles simulations, we predict a two-dimensional material, the B2C16 monolayer, as a promising anode substitute for graphite, exhibiting outstanding dynamic, mechanical, and thermal stability. Furthermore, we construct the B2C16 bilayer and B2C16/Graphene heterostructure to explore the adsorption and diffusion behavior of Li atoms. Our computational findings reveal three key points: (1) Lithium demonstrates stable adsorption on the B2C16 monolayer with an optimal adsorption energy of −1.20 eV. The binding strength of Li is improved in the bilayer B2C16 (−1.61 eV) and the B2C16/Graphene heterostructure (−1.41 eV). (2) The B2C16 monolayer exhibits a remarkable specific capacity of 1253 mA h g−1, a moderate average open-circuit voltage (OCV) of 0.76 V, and a minimal volume expansion of 0.7% during lithiation, showcasing exceptional cycling stability. (3) Lithium diffusion energy barriers decrease from 0.18–1.14 eV (monolayer) to 0.14–0.58 eV (bilayer), enabling enhanced kinetics, while the B2C16/Graphene heterostructure shows diffusion energy barriers of 0.37–0.98 eV. With the balanced combination of high capacity, fast ion transport, and outstanding stability, the B2C16 monolayer represents an ideal anode candidate for advanced LIBs.