华东师范大学学报(自然科学版) ›› 2022, Vol. 2022 ›› Issue (1): 22-30.doi: 10.3969/j.issn.1000-5641.2022.01.004

• 物理学与电子学 • 上一篇    下一篇

氮掺杂碳包覆的蛋黄壳结构硅负极材料

鲍恺婧, 张召凯, 朴贤卿*(), 孙卓   

  1. 华东师范大学 物理与电子科学学院 纳光电集成与先进装备教育部工程研究中心, 上海 200241
  • 收稿日期:2021-01-08 出版日期:2022-01-25 发布日期:2022-01-18
  • 通讯作者: 朴贤卿 E-mail:xqpiao@phy.ecnu.edu.cn

Yolk-shell silicon anode material coated with nitrogen-doped carbon

Kaijing BAO, Zhaokai ZHANG, Xianqing PIAO*(), Zhuo SUN   

  1. Engineering Research Center for Nanophotonics and Advanced Instrument (Ministry of Education), School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China
  • Received:2021-01-08 Online:2022-01-25 Published:2022-01-18
  • Contact: Xianqing PIAO E-mail:xqpiao@phy.ecnu.edu.cn

摘要:

采用间苯二酚-甲醛为碳源, 三聚氰胺为氮源, 以NaOH为蚀刻剂, 成功合成氮掺杂碳包覆的蛋黄壳结构硅(Si@void@N-C)锂离子电池复合负极材料. 对样品进行XRD、 SEM和X射线电子能谱, 透射电子显微镜(TEM)和电化学测试等表征及测试. 结果表明, 成功合成了蛋黄壳结构的Si@void@N-C复合负极材料. 同时, 该复合材料具有优异的电化学性能, 以0.1 A/g的电流密度进行充放电, 首次容量可达1282.3 mAh/g, 经过100次循环后, 其比容量仍高达994.2 mAh/g, 其容量保持率为77.5%, 表现出了良好的循环性能. Si@void@N-C材料中, 氮掺杂的碳壳可以增加复合材料的导电性, 同时, 蛋黄壳结构可有效缓解硅的体积效应, 有利于形成稳定的SEI膜, 从而提高电池的循环稳定性.

关键词: 锂离子电池, 氮掺杂碳, 硅负极, 蛋黄壳结构

Abstract:

Using resorcinol-formaldehyde resin as the carbon source, melamine as the nitrogen source, and NaOH as the etchant, a nitrogen-doped carbon-coated silicon (Si@void@N-C) anode material with a yolk-shell structure was synthesized. The samples were characterized and tested by XRD, SEM and X-ray photoelectron spectroscopy, TEM, and electrochemical tests; the results confirmed that a Si@void@NC composite anode material with a yolk-shell structure was successfully synthesized. The material was found to have excellent electrochemical performance. The initial capacity reached 1282.3 mA/g after charging and discharging at a current density of 0.1 A/g. After 100 cycles, its specific capacity was as high as 994.2 mAh/g with a capacity retention of 77.5%, demonstrating good cycle performance. The nitrogen-doped carbon shell of the Si@void@N-C material helps with the electrical conductivity of the composite material. Meanwhile, the yolk-shell structure effectively alleviates the volume effect of silicon; this feature is beneficial to the formation of a stable SEI film and improves the cycle stability of the battery.

Key words: lithium-ion battery, nitrogen-doped carbon, silicon-based anode, yolk-shell structure

中图分类号: