Two-Dimensional MnO2 as a Better Cathode Material for Lithium Ion Batteries
Two-Dimensional MnO2 as a Better Cathode Material for Lithium Ion Batteries
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二维MnO2作为更好的锂离子电池正极材料
DOI：
10.1021/acs.jpcc.5b10354
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发表时间：
2015-12-31
影响因子：
3.7
通讯作者：
Li, Youyong
中科院分区：
文献类型：
--
作者：
Deng, Shuo;Wang, Lu;Li, Youyong
在第一性原理计算的基础上，我们系统地研究了锂离子在单层MnO2上的吸附和扩散，并与其他过渡金属二卤化物(TMDs)和过渡金属氧化物(TMOS)进行了比较。单层MnO_2具有较高的Li吸附能(4.37 eV)和较低的Li扩散势垒(0.148 eV)。电子分析表明，电子从Li转移到O原子的空轨道上，Li原子的S轨道与MnO_2中O原子的PZ轨道之间存在一定的轨道耦合。由于在MnO2层两侧吸附了Li，理论储锂容量高达616mAh/g。结果表明，与其他二维纳米材料相比，单层或少层MnO2在储锂容量和扩散速率方面表现出优异的性能，被认为是一种有前途的大容量锂离子电池电极材料。
On the basis of first-principles calculations, we have systematically studied the adsorption and diffusion of Li ions on monolayer MnO2 and compared with other transition metal dichalcogenides (TMDs) and transition metal dioxides (TMOs). Monolayer MnO2 shows a relatively high Li adsorption energy of 4.37 eV and low Li diffusion barrier of 0.148 eV. The electronic analysis indicates that the electron transferred from Li to the empty orbital of the O atom and there is some orbital coupling between the s orbital of the Li atom and the pz orbital of the O atom in MnO2. Due to Li adsorption on both sides of the MnO2 layer, the theoretical Li storage capacity reaches as high as 616 mAh/g. Our results demonstrated that, compared to other two-dimensional (2D) nanomaterials, monolayer or few-layer MnO2 exhibits excellent performance on Li storage capacity and diffusion rate and is believed to be a promising electrode material for high-capacity Li ion batteries.