Atomic layer deposition of ZnO/TiO2 nanolaminates as ultra-long life anode material for lithium-ion batteries

摘要

In this work, we designed ZnO/TiOsub2/sub nanolaminates by atomic layer deposition (ALD) as anode material for lithium ion batteries. ZnO/TiOsub2/sub nanolaminates were fabricated on copper foil by depositing unit of 26 cycles ZnO/26 cycles TiOsub2/sub repeatedly using ALD. ZnO/TiOsub2/sub nanolaminates are much more stable than pristine ZnO films during electrochemical cycling process. Therefore, ZnO/TiOsub2/sub nanolaminates exhibit excellent lithium storage performance with an improved cycling performance and superior rate capability compared to pristine ZnO films. Moreover, coulombic efficiency (CE) of ZnO/TiOsub2/sub nanolaminates is above 99%, which is much higher than the value of pristine ZnO films. Excellent ultralong-life performance is gained for ZnO/TiOsub2/sub nanolaminates, retaining a reversible capacity of ~667 mAh gsup-1/sup within cut-off voltage of 0.05-2.5?V after 1200 cycles of charge-discharge at 500?mA?gsup-1/sup. Constructing nanolaminates structures via ALD might open up new opportunities for improving the performance of anode materials with large volume expansion in lithium ion batteries.