Bismuth Nanoparticles Encapsulated in Mesoporous Carbon as Anodes for Sodium- and Potassium-Ion Batteries

With abundant resources, high electrochemical reversibility, and high volumetric specific capacity, bismuth (Bi) has been identified as a promising anode candidate for both potassium-ion batteries (PIBs) and sodium-ion batteries (SIBs). However, its relatively large volumetric change during the charging/discharging processes has hindered the practical application of Bi. To alleviate these problems, a single-step vapor-phase nanocrystallization method has been utilized to distribute Bi nanoparticles to ordered mesoporous carbon CMK-3, forming the Bi/CMK-3 composite. The large volumetric change will be largely eased thanks to the nanosize effect of Bi particles. As a result, the Bi/CMK-3 anode has delivered a reversible capability of 249 mAh g –1 at 20 A g –1 for SIBs and a reversible capability of 231 mAh g –1 at 20 A g –1 for PIBs, respectively, indicating its quick-charging potential. A capacity of 210 mAh g –1 at 10 A g –1 and a capacity of 203 mAh g –1 at 1 A g –1 have been maintained after cycling over 2500 and 500 cycles for SIBs and PIBs, respectively, showing the stable cycling performance of the Bi/CMK-3 anode.