Engineering of yolk-shelled FeSe_(2)@nitrogen-doped carbon as advanced cathode for potassium-ion batteries

作     者：Chang Liu Yujie Li Yanhong Feng Sen Zhang Di Lu Boyun Huang Tao Peng Weiwei Sun Chang Liu;Yujie Li;Yanhong Feng;Sen Zhang;Di Lu;Boyun Huang;Tao Peng;Weiwei Sun

作者机构：College of Aerospace Science and EngineeringNational University of Defense TechnologyChangsha 410073China School of Physics and ElectronicsHunan UniversityChangsha 410082China School of Physics and Electronic EngineeringXinyang Normal UniversityXinyang 464000China 

出 版 物：《Chinese Chemical Letters》 (中国化学快报（英文版）)

年 卷 期：2021年第32卷第11期

页      面：3601-3606页

核心收录：

学科分类：0808[工学-电气工程] 08[工学] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：the financial support from the National Postdoctoral Program for Innovation Talents(No.BX201700103) China Postdoctoral Science Foundation Funded Project(No.2018M633664) 

主　　题：Potassium battery Yolk-shell structure FeSe_(2) Conversion-type cathode High energy density 

摘      要：Potassium-ion batteries(KIBs)have become the most promising alternative to lithium-ion batteries for large-scale energy storage system due to their abundance and low ***,previous reports focused on the intercalation-type cathode materials usually showed an inferior capacity,together with a poor cyclic life caused by the repetitive intercalation of large-size K-ions,which hinders their practical ***,we combine the strategies of carbon coating,template etching and hydrothermal selenization to prepare yolk-shelled FeSe_(2)@N-doped carbon nanoboxes(FeSe_(2)@C NBs),where the inner highly-crystalline FeSe_(2)clusters are completely surrounded by the self-supported carbon *** integrated and highly conductive carbon shell not only provides a fast electron/ion diffusion channel,but also prevents the agglomeration of FeSe_(2)*** evaluated as a conversion-type cathode material for KIBs,the FeSe_(2)@C NBs electrode delivers a relatively high specific capacity of 257 mAh/g at 100 mA/g and potential platform of about 1.6 V,which endow a high energy density of about 411 Wh/*** importantly,by designing a robust host with large internal void space to accommodate the volumetric variation of the inner FeSe_(2)clusters,the battery based on FeSe_(2)@C NBs exhibits ultra-long cycle ***,even after 700 cycles at 100 mA/g,a capacity of 221 mAh/g along with an average fading rate of only 0.02%can be retained,which achieves the optimal balance of high specific capacity and long-cycle stability.