金属离子导体,LiNiNN的晶体化学和电子结构
Zlatka Stoeva1, Bernd Jäger, Ruben Gomez
1School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, U.K.
Journal of the American Chemical Society
|January 31, 2007
概括
层状化物LiNiN具有快速离子扩散和金属性质,使其成为离子电池电极的有前途材料. 它独特的结构和结合有助于这些有利的特性.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 电化学 电化学 电化学
背景情况:
- 层状三元化物正在探索用于先进的储能应用.
- 化 (Li3N) 作为相关化合物的母结构.
- 快速离子扩散和金属行为是电池电极材料的理想特性.
研究的目的:
- 为了研究分层三元化物LiNiN的结构和特性.
- 评估LiNiN作为离子电池的电极材料的潜力.
- 了解结构,结合和电化学性质之间的关系.
主要方法:
- 在可变温度下进行粉末中子衍射.
- 电子结构的初始计算.
- SQUID磁力测量用于磁性属性.
- 固态核磁共振 (NMR) 光谱学. 固态核磁共振 (NMR) 光谱学.
主要成果:
- LiNiN 构成了 Li3N 结构的一个变体,具有有序的 Li+ 空位和层间位置的 Ni (六角空间组 Pm2).
- 最初的计算表明LiNiN是由于沿c轴的Ni-Npi和Sigma结合而形成的一维金属.
- 可变温度中子衍射和固态7Li NMR证实了快速的Li+离子运动和金属行为.
结论:
- 尼具有独特的晶体结构,有利于快速的离子运输.
- 证实了材料的单维金属性质,由特定的Ni-N粘合引起的.
- 尼显示出作为高性能离子电池的电极材料的巨大潜力.
相关概念视频
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