原子层沉积氧化铝包覆层增强五氧化二钒多孔薄膜电化学循环稳定性

Enhanced electrochemical stability induced by atomic layer deposition of Al_2O_3 coatings on V_2O_5 porous film

最近,包覆氧化物进行表面修饰的方法已成功应用于改善锂离子电池阴极材料的容量稳定性。本文中,我们通过V2O5溶胶结合提拉法制备了V2O5多孔薄膜,并利用原子层沉积法对其包覆Al2O3原子层。V2O5多孔薄膜的电化学性质受包覆层厚度的影响,我们研究了不同薄膜厚度下的修饰效果。结果显示,原子层沉积法包覆不同厚度Al2O3原子层对锂离子电池的循环稳定性都有所改善,经10个ALD包覆循环的样品表现出最好的修饰效果。在此基础上,我们讨论探索了包覆Al2O3对容量及稳定性增强的机理。

Surface modification by coating oxides has been applied to improve the cyclic stability of cathode materials for rechargeable lithium-ion batteries. In this article, we systematically compared the improvement that resulted from different layers of Al2O3 coatings via atomic layer deposition （ALD）on V2O5 thin films. The porous V2O5 thin films were prepared by dip-coating method with vanadium oxide so1. The results reveal that the Al2O3 coatings have a positive effect to the cyclic durability. The film deposited by 10 layers of Al2O3 exhibits the best cyclic performance. Moreover, we further discussed the mechanism of the stability and capacity enhancement aroused from Al2O3 depositions.