Potassium ion batteries(PIBs)are of great interest owing to the low cost and abundance of potassium resources,while the sluggish diffusion kinetics of K^(+)in the electrode materials severely impede their practical ap...Potassium ion batteries(PIBs)are of great interest owing to the low cost and abundance of potassium resources,while the sluggish diffusion kinetics of K^(+)in the electrode materials severely impede their practical applications.Here,self-hybridized BiOCl_(0.5)Br_(0.5) with a floral structure is assembled and used as anode for PIBs.Based on the systematic theoretical calculation and experimental analysis,the unbalance of charge distribution between Cl and Br atoms leads to an enhanced built-in electric field and a larger interlayer spacing,which can enhance the K^(+)diffusion.Furthermore,the K^(+)insertion causes the energetic evolution of polar states in the BiOCl_(0.5)Br_(0.5) crystal framework,where the dynamic correlation between the K^(+)and the halogen atoms leads to the formation of hole-like polarons,which significantly improves the K^(+)diffusion and reaction kinetics during the charging/discharging process,giving important implications to design the electrode materials with high electrochemical performance by engineering the interaction between electronic structure and interface.Therefore,the BiOCl_(0.5)Br_(0.5) anode obtains an excellent performance of 171 mAh·g^(-1) at 1 A·g^(-1) over 2000 cycles in PIBs.展开更多
基金financially supported by the National Natural Science Foundation of China(52001151 and 22305106)Postdoctoral Fellowship Program of CPSF(GZC20230682)+2 种基金Natural Science Foundation of Henan Province(202300410068)Fujian Province(2022J05104)the Science and Technology Foundation for Youths of Gansu Province(21JR7RA518 and 23JRRA1111).
文摘Potassium ion batteries(PIBs)are of great interest owing to the low cost and abundance of potassium resources,while the sluggish diffusion kinetics of K^(+)in the electrode materials severely impede their practical applications.Here,self-hybridized BiOCl_(0.5)Br_(0.5) with a floral structure is assembled and used as anode for PIBs.Based on the systematic theoretical calculation and experimental analysis,the unbalance of charge distribution between Cl and Br atoms leads to an enhanced built-in electric field and a larger interlayer spacing,which can enhance the K^(+)diffusion.Furthermore,the K^(+)insertion causes the energetic evolution of polar states in the BiOCl_(0.5)Br_(0.5) crystal framework,where the dynamic correlation between the K^(+)and the halogen atoms leads to the formation of hole-like polarons,which significantly improves the K^(+)diffusion and reaction kinetics during the charging/discharging process,giving important implications to design the electrode materials with high electrochemical performance by engineering the interaction between electronic structure and interface.Therefore,the BiOCl_(0.5)Br_(0.5) anode obtains an excellent performance of 171 mAh·g^(-1) at 1 A·g^(-1) over 2000 cycles in PIBs.
