Two-dimensional AlB4/Al2B2: high-performance Dirac anode materials for sodium-ion batteries

• Published in: Physical chemistry chemical physics : PCCP Vol. 25; no. 42; pp. 28814 - 28823
• Main Authors: Ru-Feng Zou, Xiao-Juan, Ye, Xiao-Hong, Zheng, Jia, Ran, Chun-Sheng, Liu
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 01.11.2023
• Subjects: Anodes; Batteries; Bilayers; Diffusion barriers; Electrode materials; First principles; Mathematical analysis; Monolayers; Open circuit voltage; Sodium; Sodium-ion batteries; Storage capacity
• ISSN: 1463-9076; 1463-9084
• DOI: 10.1039/d3cp03649a

Sodium-ion batteries (SIBs) have attracted much attention due to their abundant earth-reserves and low cost. Two-dimensional (2D) Dirac materials show great application prospects as anodes for SIBs because of their excellent electronic conductivity. We explore the performances of AlB4 (Al2B2) monolayers and bilayers as anodes for SIBs by using first-principles calculations. The AlB4 (Al2B2) monolayer exhibits a high theoretical storage capacity of 954.15 (709.17) mA h g−1 and a low diffusion barrier of 0.36 (0.03) eV. The calculated average open-circuit voltage (0.68/0.18 V) falls within the acceptance range of 0.1–1.0 V for anode materials. The fully sodiated AlB4 (Al2B2) monolayer shows a tiny lattice expansion of 0.9% (2.4%), suggesting good reversibility. Furthermore, in comparison with the AlB4 (Al2B2) monolayer, the AlB4 (Al2B2) bilayer can provide stronger binding with Na on the outside surface. These results contribute to a better understanding of the AlB4 (Al2B2) monolayers and bilayers as potential high-performance anode materials for SIBs.