In-situ encapsulation of α-Fe2O3 nanoparticles into ZnFe2O4 micro-sized capsules as high-performance lithium-ion battery anodes

• 作者: Wei Wu Yongshan Wei Hongjiang Chen Keyan Wei Zhitong Li Jianhui He Libo Deng Lei Yao Haitao Yang
• 来源期刊: 材料科学技术（英文版）
• 年，卷（期）: 2021,（16）
• 页码范围: 110-117
• 页数: 8页
• 语种: 英文

摘要

Transition metal oxides as anode materials for high-performance lithium-ion batteries suffer from severe capacity decay,originating primarily from particle pulverization upon volume expansion/shrinkage and the intrinsically sluggish electron/ion transport.Herein,in-situ encapsulation of α-Fe2O3 nanoparticles into micro-sized ZnFe2O4 capsules is facilely fulfilled through a co-precipitation process and followed by heat-treatment at optimal calcination temperature.The porous ZnFe2C4 scaffold affords a synergistic confinement effect to suppress the grain growth of α-Fe2O3 nanocrystals during the calcination process and to accommodate the stress generated by volume expansion during the charge/discharge process,leading to an enhanced interfacial conductivity and inhibit electrode pulverization and mechanical failure in the active material.With these merits,the prepared α-Fe2O3/ZnFe2O4 composite delivers prolonged cycling stability and improved rate capability with a higher specific capacity than sole α-Fe2O3 and ZnFe2O4.The discharge capacity is retained at 700 mAh g-1 after 500 cycles at 200 mA g-1 and 940 mAh g-1 after 50 cycles at 100 mA g-1.This work provides a new perspective in designing transition metal oxides for advanced lithium-ion batteries with superior electrochemical properties.