Theoretical investigation of the doping effect on interface storage in the graphene/silicene heterostructure as the anode for lithium-ion batteries

• Published in: Energy Materials and Devices Vol. 1; no. 2; p. 9370020
• Main Authors: Fen Yao, Junling Meng, Xuxu Wang, Jinxian Wang, Limin Chang, Gang Huang
• Format: Journal Article
• Language: English
• Published: Tsinghua University Press 01.12.2023
• Subjects: doping; first-principles calculations; heterostructure; lithium-ion battery
• ISSN: 3005-3315; 3005-3064
• DOI: 10.26599/EMD.2023.9370020

Van der Waals heterostructures made up of different two-dimensional (2D) materials have garnered considerable attention as anodes for lithium-ion batteries (LIBs), and doping can significantly influence their electronic structures and lithium diffusion barriers. In this work, the effects of heteroatom (X = N, O, P, and S) doping in the graphene of the graphene/silicene (G/Si) heterostructure are comprehensively examined by using first-principles calculations. The stacking stability and mechanical stiffness of G/Si and doped G/Si (XG/Si) exhibit that N-doping can improve the structural stability of G/Si, thereby ensuring good cycling performance. The densities of states reveal that the dopants (N, O, and S) can greatly increase the electronic conductivity of G/Si. Importantly, the adsorption and diffusion behaviors of Li are primarily affected by the dopant and the doping site, resulting in ultrafast Li diffusivity. Therefore, N-doped G/Si at doping site 1 (S1) shows a good and balanced property, which exhibits high potential to enhance the electrical performance of G/Si materials and offers a reference for selecting dopants in other 2D anode materials for LIBs.