| 摘要: |
| 采用密度泛函理论（DFT）研究了二维单层Si3N作为离子电池阳极材料的相关性能.零带隙能带结构表明,单层Si3N具有金属特性,金属的高导电能力有利于其作为阳极材料.计算结果表明,单层Si3N对于钠和钾的理论容量分别为1 230 mAh·g-1和889 mAh·g-1.与此同时,该材料对钠和钾的理论能量密度分别为1 090 mWh·g-1和576 mWh·g-1,高于之前一些报道的二维阳极材料.此外,钠、钾原子在单层Si3N上的扩散势垒分别为0.30,0.38 eV,表明该材料具有非常高的充放电速率,且在吸附过程中,Si3N一直保持着良好的金属特性和结构完整性,这些性质使其具有良好的电池工作循环性能.以上结果表明,单层Si3N是理想的钠/钾离子电池阳极材料. |
| 关键词: 二维 密度泛函理论（DFT） 单层Si3N 钠和钾离子电池 |
| DOI：10.3969/J.ISSN.1000-5137.2023.05.005 |
| 分类号:TU 528.41 |
| 基金项目:上海市自然科学基金（19ZR1437300） |
|
| Monolayer Si3N as a high-capacity anode material for ultrafast charging Na/K-ion batteries |
|
WANG Mengke, HOU Zhongqing, WANG Shuailong, SUN Shoutian, YE Xiang
|
|
Mathematics and Science College, Shanghai Normal University, Shanghai 200234, China
|
| Abstract: |
| In this work, we have studied 2D monolayer Si3N using density functional theory （DFT）. The zero gap band structure shows that the Si3N is of metal properties, which is favorable for anode material. The high specific capacity of Na and K is expected to be 1 230 mAh·g-1 and 889 mAh·g-1, respectively. Meanwhile, the theoretical energy densities of Na and K are 1 090 mWh·g-1 and 576 mWh·g-1, respectively, which are much higher than some previously reported 2D material anodes. In addition, the predicted diffusion barrier for adsorption of Na, K ions is 0.30, 0.38 eV, which indicates that this material has a very high rate capacity. In the process of Na/K ion intercalation, the metallic characteristics and structural integrity of Si3N are maintained, which makes it have good working cycle and conductive performance of the battery. These results indicate that Si3N can be used as an ideal anode material for sodium and Na/K-ion. |
| Key words: two-dimensional density functional theory（DFT） monolayer Si3N sodium and potassium -ion batteries |
