高能密度锂离子全电池微球Si @ Graphene复合阳极中石墨烯杂原子的控制,ACS Sustainable Chemistry & Engineering

当前位置： X-MOL 学术 › ACS Sustain. Chem. Eng. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

高能密度锂离子全电池微球Si @ Graphene复合阳极中石墨烯杂原子的控制
ACS Sustainable Chemistry & Engineering ( IF 7.1 ) Pub Date : 2020-12-15 , DOI: 10.1021/acssuschemeng.0c06169
Anif Jamaluddin, Bharath Umesh, Kuo-Hao Tseng, Chun-Wei Huang, Fuming Chen, Jeng-Kuei Chang, Ching-Yuan Su

使用硅和氮掺杂的石墨烯来制造锂离子电池（LIB）中的复合阳极引起了广泛的关注。但是，报告的策略仅限于实现具有成本效益，可伸缩且轻便的方法。特别是，许多关于Si / N-石墨烯（N-Gra）阳极的报告无法实现高的首次放电容量，而又不能保持高的库仑效率（CE）。在本文中，我们报道了一种Si @ N-Gra复合材料，该复合材料具有以NP ₃为核壳的微球和以NH ₃为氮源的电化学剥离石墨烯。我们使用H ₂和NH ₃以控制O和N含量并优化阳极性能。发现Si @ N-Gra复合阳极中的N-Gra极大地改善了电导率和离子迁移率。结果，微球结构（Si @ N-ECGB）在85.2％的CE下表现出最高的初始放电容量，高达2604.5 mAh / g。出色的性能归因于有效的锂化/去锂化，可保持Si @ N-ECGB的稳定性。展示了一个完整的Si @ N-ECGB || NMC 811电池（Ni / Mn / Co = 8：1：1），该电池具有很高的初始容量（170 mAh / g）和100个循环后约84％的保留率实现。这项工作为实现LIB的高容量和稳定性提供了潜在的策略。

"点击查看英文标题和摘要"

Control of Graphene Heteroatoms in a Microball Si@Graphene Composite Anode for High-Energy-Density Lithium-Ion Full Cells

The use of Si and nitrogen-doped graphene to fabricate composite anodes in lithium-ion batteries (LIBs) is attracting intense attention. However, the reported strategies are limited to achieving a cost-effective, scalable, and facile approach. In particular, many reports on Si/N-graphene (N-Gra) anodes cannot achieve a high first discharge capacity while retaining a high Coulombic efficiency (CE). Herein, we report a Si@N-Gra composite with core–shelled microballs of Si NPs and electrochemically exfoliated graphene by NH₃ as a nitrogen source. We use H₂ and NH₃ to control the O and N content and to optimize the anode performance. It is found that N-Gra in the Si@N-Gra composite anode highly improves the electric conductivity and ion mobility. As a result, the microballs structure (Si@N-ECGB) exhibit the highest initial discharge capacity of up to 2604.5 mAh/g with an 85.2% CE. This excellent performance is attributed to efficient lithiation/delithiation that maintains the stability of the Si@N-ECGB. A full cell of Si@N-ECGB||NMC 811 (Ni/Mn/Co = 8:1:1) is demonstrated, from which a high initial capacity (170 mAh/g) and ∼84% retention after 100 cycles are achieved. This work provides a potential strategy for achieving high capacity and stability in LIBs.

更新日期：2020-12-15

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南