Theoretical study on single-side fluorinated graphene for lithium storage

• Published in: Applied surface science 2021-09, Vol.560, p.150033, Article 150033
• Main Authors: Chen, Shangqian, Zheng, Fangfang, Feng, Jie, Dong, Huilong, Li, Youyong
• Format: Article
• Language: English
• Subjects: Density functional calculation; Graphene; Lithium storage; Single-side fluorination
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2021.150033

[Display omitted] •DFT simulations was performed for single-side fluorinated graphene as lithium storage materials.•The Li storage performance of SSF graphene varies with the concentration of fluoride.•Ultra-low lithium ion diffusion barrier (0.04 eV) was found on the surface of C2F.•The C2F with high fluorination ratio as promising lithium storage material. Fluorinated graphene and its derivatives have been widely applied as anode materials in energy batteries nowadays. In this work, we systematically study the case of lithium atoms absorbed on fluorine-free side of single-side fluorinated graphene (CnF) with varied fluorine contents (n = 2, 6 and 8) by density functional theory simulations. The surfaces of fluorine-free side of CnF are all energetically favorable for adsorption of lithium. Systematic analysis on the electronic properties of Li-CnF structures are performed by differential charge density, Bader charge transfer and electron projected density of states. Among the three structures, C2F exhibits an excellent lithium storage performance, with extremely low lithium ion diffusion barrier (0.04 eV), high open circuit voltage (0.96 V) and acceptable maximum lithium storage capacity (623 mAh/g). Our results suggest that the single-side fluorination of graphene is a promising approach for lithium storage.