Ni-Co Double Hydroxide Grown on Graphene Oxide for Enhancing Lithium Ion Storage

It still remains a major challenge to maintain the excellent lithium ion-storage performance of layered double hydroxide (LDH) for lithium ion battery anodes at high current density and long cycle times. Herein, a hybrid material was developed by anchoring Co/Ni/ LDH (CoNi-LDH) on the surface of graphene oxide (GO) to obtain good structural stability. During the growth process, the β phase with a low value (4.6 Å) of interlayer spacing was converted to the α phase with a high value (8.1 Å) of interlayer spacing and the sheet became thinner than that of CoNi-LDH alone. X-ray photoelectron spectroscopy (XPS) results demonstrate the formation of the C═O chemical bond between the ultra thin CoNi-LDH and GO, which increased the structural stability and effectively reduced the charge-transfer impedance. As expected, the long-life cycling stability with a specific capacity of 440 mAh/g for 500 cycles was achieved at a high current density of 5 A/g, indicating that the structural degradation of CoNi-LDH was successfully suppressed by the introduction of GO.