Energy storage performance of Vn+1Cn monolayer as electrode material studied by first-principles calculations
Energy storage performance of Vn+1Cn monolayer as electrode material studied by first-principles calculations
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第一性原理计算研究Vn 1Cn单层电极材料的储能性能
DOI：
10.1039/c6ra04034a
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发表时间：
2016-01-01
期刊：
影响因子：
3.9
通讯作者：
Zhang, Xitian
中科院分区：
文献类型：
--
作者：
Bai, Lina;Yin, Haitao;Zhang, Xitian
二维过渡金属碳化物由于具有高导电性、大的阳离子存储能力和独特的机械性能而被期望成为潜在的负极材料。本文对Vn+1Cn单分子膜的Li原子存储容量和扩散行为进行了理论分析。据预测，V3C2和V4C3单层可以通过选择性蚀刻相应的V3AlC2和V4AlC3相的Al层来合成。Vn+1Cn单层被发现是金属字符具有高的总态密度在费米能级。此外，与其他碳基材料相比，Vn+1Cn表面可以被锂吸附，具有低扩散势垒和高存储能力。为了提高性能，在实际合成实验中应避免表面功能化。上述研究结果提供了对Vn+1Cn单层的储能性能的深入了解，并预测尚未合成的V3C2和V4C3单层是有希望的电极材料的候选者。
Two-dimensional transition metal carbides are expected to be potential negative electrode materials, due to high conductivity, large cation storage capabilities, and unique mechanical properties. In this work, theoretical analysis of Li atom storage capacity and diffusion behavior of the Vn+1Cn monolayer are investigated. It is predicted that the V3C2 and V4C3 monolayers can be synthesized through selective etching of Al layers of the corresponding V3AlC2 and V4AlC3 phases. The Vn+1Cn monolayer is found to be of metallic character with a high total density of states at the Fermi level. Moreover, Vn+1Cn surfaces can be adsorbed by lithium with a low diffusion barrier and high storage capabilities compared with other carbon-based materials. To enhance performance, the surface functionalization should be avoided in the practical synthetic experiments. The above study results provide insight into the energy storage performance of the Vn+1Cn monolayer, and predict that the not yet synthesized V3C2 and V4C3 monolayers are promising candidates for electrode materials.