Highly Efficient Na+ Storage in Uniform Thorn Ball-Like a-MnSe/C Nanospheres

• 作者: Zhenzhe Li Shuhao Xiao Jiawei Liu Xiaobin Niu Yong Xiang Tingshuai Li Jun Song Chen
• 来源期刊: 金属学报（英文版）
• 年，卷（期）: 2021,（3）
• 所属期刊栏目: Special Issue:Anode Materials for Rechargeable Batteries
• 页码范围: 373-382
• 页数: 10页
• 语种: 英文

摘要

Because of its high theoretical capacity,MnSe has been identified as a promising candidate as the anode material for sodiumion batteries.However,its fast capacity deterioration due to the huge volume change during the intercalation/deintercalation of sodium ions severely hinders its practical application.Moreover,the sodium storage mechanism of MnSe is still under discussion and requires in-depth investigations.Herein,the unique thorn ball-like α-MnSe/C nanospheres have been prepared using manganese-containing metal organic framework (Mn-MOF) as a precursor followed by in situ gas-phase selenization at an elevated temperature.When serving as the anode material for sodium-ion battery,the as-prepared α-MnSe/C exhibits enhanced sodium storage capabilities of 416 and 405 mAh g-1 at 0.2 and 0.5 A g-1 after 100 cycles,respectively.It also shows a superior capacity retention of 275 mA h g-1 at 10 A g-1 after 2000 cycles,and a rate performance of 279 mA h g-1 at 20 A g-1.Such sodium storage properties could be attributed to the unique structure offering a highly efficient Na+ diffusion kinetics with a diffusion coefficient between 1 × 10-11 and 3 × 10-10 cm2 s-1.The density functional theory calculation indicates that the fast Na+ diffusion mainly takes place on the (100) plane of MnSe along a V-shaped path because of a relatively low diffusion energy barrier of 0.15 eV.