Investigations on V2C and V2CX2 (X = F, OH) Monolayer as a Promising Anode Material for Li Ion Batteries from First-Principles Calculations

详细信息    查看全文

• 作者：Junping Hu ; Bo Xu ; Chuying Ouyang ; Shengyuan A. Yang ; Yugui Yao
• 刊名：Journal of Physical Chemistry C
• 出版年：2014
• 出版时间：October 23, 2014
• 年：2014
• 卷：118
• 期：42
• 页码：24274-24281
• 全文大小：477K
• ISSN：1932-7455

文摘

First-principles calculations are performed to study the electronic properties and Li storage capability of V₂C and its corresponding fluoride and hydroxide. We find that the V₂C monolayer is metallic with antiferromagnetic configuration, while its derived V₂CF₂ and V₂C(OH)₂ in their the most stable configurations are small-gap antiferromagnetic semiconductors. Li adsorption could enhance the electric conductivity of V₂C fluoride and hydroxide. The bare V₂C monolayer shows fast Li diffusion with low diffusion barrier height and very high Li storage capacity (with theoretical value 鈭?40 mAh/g), while the passivated F or OH atoms on its surface tend to impede Li diffusion and largely reduce the Li storage capacity. Moreover, the average intercalation potentials for V₂C-based materials are calculated to be relatively low. Our results suggest that V₂C monolayer could be a promising anode material for Li-ion batteries.