In Situ Fabrication of Carbon-Encapsulated Fe7X8 (X = S, Se) for Enhanced Sodium Storage
In Situ Fabrication of Carbon-Encapsulated Fe7X8 (X = S, Se) for Enhanced Sodium Storage
复制标题
原位制造碳封装 Fe7X8 (X = S, Se) 以增强钠储存
DOI：
10.1021/acsami.9b00500
复制
发表时间：
2019-05-29
影响因子：
9.5
通讯作者：
Yang, Chenghao
中科院分区：
文献类型：
--
作者：
Liu, Tiezhong;Li, Youpeng;Yang, Chenghao
由于地壳中天然丰富的钠，钠离子电池（SIB）被认为是锂离子电池的有前途的替代品。本工作采用一步热解法制备了梭形Fe（7）X（8）pC（X = S，Se）复合材料。形成的碳骨架可以防止Fe 7 X8纳米粒子的团聚，并稳定氧化还原反应中产生的Fe/Na 2X界面。Fe7X8@C（X = S，Se）具有优异的可逆比容量（对于Fe7S8@C，在0.2 A g（-1）下为1005.3 mAh g（-1），对于Fe7Se8@C，在0.5 A g（-1）下为458.5 mAh g（-1）），出色的速率性能（对于Fe7S8@C为654.7 mAh g（-1），对于Fe7Se8@C为392.9 mAh，即使在2 A g（-1）下也通过300个回路），和优异的循环性能（对于Fe（7）Se（8）pC，在0.2A g（-1）下50次循环后795.8mAh g（-1）和在0.5A g（-1）下150次循环后399.9mAh g（-1））。Fe7X8@C复合材料优异的电化学性能使其成为理想的SIB负极材料。
Sodium-ion batteries (SIBs) have been regarded as a promising alternative to lithium-ion batteries due to the natural abundance of sodium in the earth's crust. In our work, fusiform Fe(7)X(8)pC (X = S, Se) composites were obtained via a one-step pyrolysis strategy applied to SIB anode materials. The formed carbon skeleton could prevent the Fe7X8 nanoparticles from agglomeration and stabilize the interface of Fe/Na2X generated in the redox reactions. Fe7X8@C (X = S, Se) exhibits excellent reversible specific capacity (1005.3 mAh g(-1) under 0.2 A g(-1) for Fe7S8@C and 458.5 mAh g(-1) under 0.5 A g(-1) for Fe7Se8@C), outstanding rate performance (654.7 mAh g(-1) for Fe7S8@C and 392.9 mAh for Fe7Se8@C going through 300 loops even under 2 A g(-1)), and excellent cycling properties (795.8 mAh g(-1) after 50 loops under 0.2 A g(-1) for Fe7S8@C and 399.9 mAh g(-1) going through 150 loops under 0.5 A g(-1) for Fe(7)Se(8)pC). The excellent electrochemical performance of Fe7X8@C composites makes them promising anode materials for SIBs.