Layered mesoporous CoO/reduced graphene oxide with strong interfacial coupling as a high-performance anode for lithium-ion batteries

Abstract

Composites of few-layer transition metal oxides and graphene nanosheets with strong interfacial connection hold great promise as high-performance anodes for lithium-ion batteries, but it is highly challenging to realize full interfacial properties. Herein, we report an ultra-refined layer-by-layer mesoporous CoO/reduced graphene oxide (CoO/RGO) architecture synthesized via a facile method. The CoO/RGO has stacked interfaces between the CoO nanosheets and the graphene nanosheets via Co–O–C bonds, which has been proposed to have an important role in achieving excellent performance in lithium ion batteries with high initial capacity and good rate capability. It is shown that the CoO/RGO exhibits a high initial discharge capacity of 2189.4 mAh g−1 at a current density of 100 mA g−1. Furthermore, the CoO/RGO exhibits a high reversible capacity retention of 70% after prolonged 300 cycles at a high rate of 2 A g−1. Significantly, it delivers an ultrahigh reversible capacity of 1167 mAh g−1 at 5 A g−1 with an excellent reversible capacity retention of 76% over 40 cycles.