掺杂Pr3+的尖晶石LiPrxMn2-xO4的合成及电化学性能

Synthesis and Electrochemical Properties of Pr3+-doped LiPrxMn2-xO4 Spinel

摘要:

采用溶胶凝胶法合成掺杂稀土镨离子的锂锰尖晶石LiPrxMn2-xO4，并对其结构和电化学性能进行初步研究。结果表明，当掺入的Pr3+含量较低（x≤0.02）时，得到的产物能保持完整的尖晶石结构，并表现出极佳的电化学性能。Pr3+的掺入使材料的循环稳定性能大幅度提高，而这种提高是源于Pr3+对尖晶石结构的稳定作用。电极材料LiPr0.02Mn1.98O4显示了最优的电化学性能，在0.2 C放电速率下，其初始放电容量为118 mAh·g-1，100次循环后仍能保持初始容量的98%。

关键词:尖晶石LiMn2O4;掺杂;镨;锂离子电池

Abstract:

Praseodymium doped spinel LiPrxMn2-xO4 with single phase was synthesized by Sol-gel route. Its structure and electrochemical properties were studied by XRD, XPS and electrochemical measurements. The results show that when the doped Pr content is low (x≤0.02), the obtained product can maintain the whole spinel structure and exhibit excellent electrochemical properties. Pr3+ doping increases the cycle stability of the material greatly, which results from its stabilization for the spinel structure. The electrode of LiPr0.02Mn1.98O4 shows optimal electrochemical properties with a first discharge capacity of 118 mAh·g-1 and 98% of the initial capacity after 100 cycles at the current rate of 0.2 C. As cathode material of lithium-ion battery, this praseodymium doped spinel material is one of the most promising substitutes for LiCoO2.

Key words:spinel LiMn2O4; doping; Pr; lithium ion battery