标题: Electrochemical Conversion of Silica Nanoparticles to Silicon Nanotubes in Molten Salts: Implications for High-Performance Lithium-Ion Battery Anode

作者: Wang, F (Wang, Fan); Ma, YS (Ma, Yongsong); Li, P (Li, Peng); Peng, C (Peng, Chuang); Yin, HY (Yin, Huayi); Li, W (Li, Wei); Wang, DH (Wang, Dihua)

来源出版物: ACS APPLIED NANO MATERIALS卷: 4期: 7页: 7028-7036 DOI: 10.1021/acsanm.1c01061出版年: JUL 23 2021

摘要: Understanding the material formation mechanism is critical to guide the material synthesis and exploitation. Herein, we reveal a different conversion mechanism of SiO2 particles to Si nanotubes (SNTs) in the molten salt electrolysis. Unlike conventional strategies employing templates and/or catalysts, the one-step electrochemical synthesis is template- and catalyst-free, which process involves lamination, exfoliation, and reduction. Specifically, SiO2 particles are first converted into layer-structured CaSiO3, from which CaO and O2- are subsequently extracted, causing the collapse of the layer structure and forming SiOx (0 < x < 2) layers. The newly formed SiOx layers are finally deeply reduced into SNTs. Besides, the morphology of silicon-based nanostructures can be controlled via altering the applied voltage between a SiO2 cathode and a graphite anode. In addition, the electrolytic SNTs show enhanced lithium-storage performances, such as a high specific capacity (2485 mAh g(-1) at 0.2 A g(-1)) and an excellent rate capability (1362 mAh g(-1) at 5 A g(-1)), which is benefited from the tube structure that can buffer the volume variation of Si. Overall, the revealed conversion mechanism will shed light on designing advanced Si-based nanomaterials for various applications.

入藏号: WOS:000677582900053

语言: English

文献类型: Article

作者关键词: deoxidation; silicon nanotubes; molten salt electrolysis; SiO2; lithium-ion batteries

地址: [Wang, Fan; Ma, Yongsong; Li, Peng; Peng, Chuang; Li, Wei; Wang, Dihua] Wuhan Univ, Sch Resource & Environm Sci, Hubei Int Sci & Technol Cooperat Base Sustainable, Wuhan 430072, Peoples R China.

[Yin, Huayi] Northeastern Univ, Key Lab Ecol Met Multimet Mineral, Minist Educ, Sch Met, Shenyang 110819, Peoples R China.

通讯作者地址: Li, W; Wang, DH (通讯作者)，Wuhan Univ, Sch Resource & Environm Sci, Hubei Int Sci & Technol Cooperat Base Sustainable, Wuhan 430072, Peoples R China.

电子邮件地址: wlimeel@whu.edu.cn;wangdh@whu.edu.cn

影响因子：5.097