Employing MXene as a matrix for loading amorphous Si generated upon lithiation towards enhanced lithium-ion storage  

作　　者：Haojie Li Ming Lu Wenjuan Han Haibo Li Yucheng Wu Wei Zhang Jiaheng Wang Bingsen Zhang 

机构地区：[1]Key Laboratory of Advanced Functional Materials and Devices of Anhui Province,School of Materials Science and Engineering,Hefei University of Technology,Hefei 230009,Anhui,China [2]Shenyang National Laboratory for Materials Science,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,Liaoning,China [3]School of Materials Science&Engineering,and Electron Microscopy Center,Jilin University,Changchun 130012,Jilin,China [4]Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education,Jilin Normal University,Siping 136000,Jilin,China [5]Key Laboratory of UV-Emitting Materials and Technology of the Ministry of Education,Northeast Normal University,Changchun 130024,Jilin,China

出　　处：《Journal of Energy Chemistry》2019年第11期50-54,共5页能源化学（英文版）

基　　金：financial support provided by the Joint Foundation of Liaoning Province National Science Foundation;Shenyang National Laboratory for Materials Science (Grant No. 20180510047);the National Natural Science Foundation of China (Grant Nos. 91545119 , 21761132025 , 21773269 and 51872115);the Youth Innovation Promotion Association CAS (Grant No. 2015152);the Program for JLU Science and Technology Innovative Research Team (JLUSTIRT, 2017TD-09);“Double-First Class” Discipline for Materials Science & Engineering;Natural Science Foundation of Anhui Province (1608085ME93);the Fundamental Research Funds for the Central Universities (JZ2018YYPY0305);the 111 Project “New Materials and Technology for Clean Energy” (B18018)

摘　　要：Although Si-based nanomaterials provide incomparable lithium ion storage ability in theory, it suffers from low initial Coulombic efficiency, electrical disconnection, and fracture due to huge volume changes after extended cycles. As a result, it leads to a severe capacity fading and an increase in internal impedance. Herein, Ti-elemental MXene was employed as a matrix for the intermediate product of Si electrodes. The boundary between the inner core of pristine Si and its outer shell of amorphous Li x Si alloy was reconstructed. Smaller amorphous aggregates were observed in the MXene&Si hybrid electrode after 500 cycles by using transmission electron microscopy. Consequently, an enhanced specific capacity was achieved as MXene as a matrix enables loading amorphous Si.Although Si-based nanomaterials provide incomparable lithium ion storage ability in theory, it suffers from low initial Coulombic efficiency, electrical disconnection, and fracture due to huge volume changes after extended cycles. As a result, it leads to a severe capacity fading and an increase in internal impedance. Herein, Ti-elemental MXene was employed as a matrix for the intermediate product of Si electrodes. The boundary between the inner core of pristine Si and its outer shell of amorphous Li x Si alloy was reconstructed. Smaller amorphous aggregates were observed in the MXene&Si hybrid electrode after 500 cycles by using transmission electron microscopy. Consequently, an enhanced specific capacity was achieved as MXene as a matrix enables loading amorphous Si.

关 键 词：Silicon Ti3C2 MXene LI-ION 

分 类 号：TG1[金属学及工艺—金属学]