Interface defect induced upgrade of K-storage properties in KFeSO4Fcathode: From lowered Fe-3d orbital energy level to advancedpotassium-ion batteries  

作　　者：Yan Liu Zhen-Yi Gu Yong-Li Heng Jin-Zhi Guo Miao Du Hao-Jie Liang Jia-Lin Yang Kai-Yang Zhang Kai Li Xing-Long Wu 

机构地区：[1]MOE Key Laboratory for UV Light-Emitting Materials and Technology,Northeast Normal University,Changchun,Jilin,130024,China [2]Faculty of Chemistry,Northeast Normal University,Changchun,Jilin,130024,China [3]State Key Laboratory of Rare Earth Resource Utilization,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun,130022,China

出　　处：《Green Energy & Environment》2024年第11期1724-1733,共10页绿色能源与环境（英文版）

基　　金：support from the National Key R&D Program of China(Grant No.2023YFE0202000);National Natural Science Foundation of China(Grant No.52102213);Science Technology Program of Jilin Province(Grant No.20230101128JC).

摘　　要：KFeSO_(4)F(KFSF)is considered a potential cathode due to the large capacity and low cost.However,the inferior electronic conductivity leads to poor electrochemical performance.Defect engineering can facilitate the electron/ion transfer by tuning electronic structure,thus providing favorable electrochemical performance.Herein,through the regulation of surface defect engineering in reduced graphene oxide(rGO),the Fe–C bonds were formed between KFSF and rGO.The Fe–C bonds formed work in regulating the Fe-3d orbital as well as promoting the migration ability of K ions and increasing the electronic conductivity of KFSF.Thus,the KFSF@rGO delivers a high capacity of 119.6 mAh g^(-1).When matched with a graphite@pitch-derived S-doped carbon anode,the full cell delivers an energy density of 250.5 Wh kg^(-1) and a capacity retention of 81.5%after 400 cycles.This work offers a simple and valid method to develop high-performance cathodes by tuning defect sites.

关 键 词：Potassium-ion batteries CATHODE Defect chemistry KFeSO4F Fe–C bond 

分 类 号：TM912[电气工程—电力电子与电力传动]