Optimization of silica-doped BxCyNz monolayer anode for high-performance potassium metal batteries through modeling study

Within this piece of research, the performances of pure B₂CN₃ nanosheet (PB₂CN₃NS) and its doped structure with Si atoms (SB₂CN₃NS) as the anode materials of K-ion batteries (KIBs) were investigated using DFT. The findings showed that PB₂CN₃NS and SB₂CN₃NS are highly capable of adsorbing K with acceptable adhesion energy (AE). Also, because of the negative adhesion of K⁺, in comparison with K, K⁺ donated more electrons on PB₂CN₃NS and SB₂CN₃NS. Based on the results, SB₂CN₃NS provided an ideal condition for the K atoms to migrate on the surfaces of PB₂CN₃NS and SB₂CN₃NS because of their lower energy barrier. The computed theoretical storage capacity was approximately 1347 mAh.g⁻¹ after the adhesion maximum K atoms onto PB₂CN₃NS and SB₂CN₃NS. This value is higher the values reported for many anodes materials fabricant in recent years. The open circuit voltage (V_OC) of PB₂CN₃NS and SB₂CN₃NS were also found to be low, which were 0.19 and 0.25 V, respectively. The outcomes within this study can provide useful insights into producing highly efficient anodes for KIBs.