BC6P Monolayer: Isostructural and Isoelectronic Analogues of Graphene with Desirable Properties for K-Ion Batteries

K-ion batteries are interesting alternatives to Li-ion batteries because of the earth-abundance of K and the similar chemistry between K and Li. However, a lack of high-performance anode materials is a major obstacle to the development of K-ion batteries. We show that the BC6P monolayer, which is isostructural and isoelectronic to graphene due to charge compensation between the constituent elements, can fill this gap. The capacity is found to be 1410 mAh/g (BC6PK6), i.e., about four times that of graphite. The diffusion barrier is as low as 0.13 eV and the average open-circuit voltage is as low as 0.35 V, ensuring high rate performance and high safety, respectively. Metallic states induced by K adsorption provide electrical conductivity during the battery cycle.

Citation

Tang, M., Wang, C., Schwingenschlögl, U., & Yang, G. (2021). BC6P Monolayer: Isostructural and Isoelectronic Analogues of Graphene with Desirable Properties for K-Ion Batteries. Chemistry of Materials. doi:10.1021/acs.chemmater.1c02957

Sponsors

The authors acknowledge funding support from the Natural Science Foundation of China under No. 21873017 and No. 21573037, the Postdoctoral Science Foundation of China under grant 2013M541283, the Natural Science Foundation of Hebei Province (B2021203030), and the Natural Science Foundation of Jilin Province (20190201231JC). The work was carried out at the National Supercomputing Center of Tianjin using TianHe-1 (A). The research reported in this publication was supported by funding from King Abdullah University of Science and Technology (KAUST).