Department of Physics, Laboratory of Computational Materials Physics, Jiangxi Normal University, Nanchang, 330022, China.
Phys Chem Chem Phys. 2019 Mar 27;21(13):7053-7060. doi: 10.1039/c8cp07398h.
Two dimensional (2D) materials have great potential for application in energy storage due to their unique structural characteristics. Here we propose for the first time a density functional theory study into the scientific feasibility of using g-Mg3N2, which is a novel graphene-like 2D material, as a high-capacity anode material for Li-ion batteries (LIBs). The favorable Li-adsorption geometries and the Li adsorption thermodynamics are explored in detail. It is found that monolayer g-Mg3N2 can be lithiated up to Li7Mg3N2 that offers a super high theoretical capacity of 1858 mA h g-1 and the average intercalation potential ranging from 0.2 to 0.7 V is suitable for anode applications. The metallic electronic structures of LixMg3N2, in combination with the low Li-ion diffusion energy barriers on the honeycomb structure, promote high electron and Li-ion conductivity to ensure fast charge/discharge cycling. The excellent structural stability of Mg3N2 is good for the cycling performance. These results predict that g-Mg3N2 can serve as a high-performance anode material for LIBs.
二维（2D）材料由于其独特的结构特性，在储能方面具有巨大的应用潜力。在这里，我们首次提出了使用 g-Mg3N2（一种新型类石墨烯 2D 材料）作为锂离子电池（LIB）高容量阳极材料的科学可行性的密度泛函理论研究。详细探讨了有利的 Li 吸附几何形状和 Li 吸附热力学。结果表明，单层 g-Mg3N2 可以被锂化到 Li7Mg3N2，其提供了超高的理论容量 1858 mA h g-1，平均嵌入电位在 0.2 到 0.7 V 之间，适合作为阳极应用。LixMg3N2 的金属电子结构，结合在蜂窝结构上的低锂离子扩散能垒，促进了高电子和锂离子电导率，以确保快速充放电循环。Mg3N2 的优异结构稳定性有利于循环性能。这些结果表明 g-Mg3N2 可用作 LIB 的高性能阳极材料。
