标题: Self-Assembly of Silicon Nanotubes Driven by a Biphasic Transition from the Natural Mineral Montmorillonite in Molten Salt Electrolysis

作者: Wang, F (Wang, Fan); Liu, W (Liu, Wei); Li, P (Li, Peng); Guan, ZH (Guan, Ziheng); Li, W (Li, Wei); Wang, DH (Wang, Dihua)

来源出版物: SMALL  DOI: 10.1002/smll.202311334  提前访问日期: FEB 2024  

摘要: Silicon nanotubes (SNTs) have been considered as promising anode materials for lithium-ion batteries (LIBs). However, the reported strategies for preparing SNTs generally have special requirements for either expensive templates or complex catalysts. It is necessary to explore a cost-effective and efficient approach for the preparation of high-performance SNTs. In this work, a biphasic transformation strategy involving "solid-state reduction" and "dissolution-deposition" in molten salts is developed to prepare SNTs using montmorillonite as a precursor. The rod-like intermediate of silicon-aluminum-calcium is initially reduced in solid state, which then triggers the continuous dissolution and deposition of calcium silicate in the inner space of the intermediate to form a hollow structure during the subsequent reduction process. The transition from solid to liquid is crucial for improving the kinetics of deoxygenation and induces the self-assembly of SNTs during electrolysis. When the obtained SNTs is used as anode materials for LIBs, they exhibit a high capacity of 2791 mAh g-1 at 0.2 A g-1, excellent rate capability of 1427 mA h g-1 at 2 A g-1, and stable cycling performance with a capacity of 2045 mAh g-1 after 200 cycles at 0.5 A g-1. This work provides a self-assembling, controllable, and cost-effective approach for fabricating SNTs.

A cost-effective method for self-assembly of silicon nanotubes has been developed using natural minerals by means of a biphasic conversion process, which does not require templates and catalysts. Meanwhile, the solution reveals the processes of "solid state reduction" during template formation and "dissolution deposition" during the generation of hollow structures. image

作者关键词: dissolution-deposition; molten salt electrochemistry; montmorillonite; silicon nanotubes; solid state reduction

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

[Wang, Fan; Guan, Ziheng] Zhejiang A&F Univ, Coll Chem & Mat Engn, Hangzhou 311300, 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：13.3