A direct hybridization between isocharged nanosheets of layered metal oxide and graphene through a surface-modification assembly process

Abstract

An efficient and universal method to directly hybridize isocharged nanosheets of layered metal oxide and reduced graphene oxide (rGO) is developed on the basis of the surface modification and an electrostatically driven assembly process. On the basis of this synthetic method, the CoO2-rGO nanocomposite can be synthesized with exfoliated CoO2 and rGO nanosheets, and transformed into CoO-CoO2-rGO nanocomposites with excellent electrode performance for lithium-ion batteries. Also, this surface-modification assembly route is successfully applied for the synthesis of another mesoporous TiO2-rGO nanocomposite. This result provides clear evidence for the usefulness of the present method as a universal way of hybridizing isocharged anionic nanosheets of inorganic solids and graphene. A universal soft-chemical synthetic route to layered metal oxide-graphene nanocomposites is developed by using the assembly between surface-modified reduced graphene oxide (rGO+) nanosheets and anionic layered metal oxide nanosheets such as CoO2 and TiO2. The resulting cobalt oxide-rGO nanocomposites show promising functionality as electrodes for lithium-ion batteries with excellent rate characteristics, underscoring the usefulness of the present lattice manipulation route. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.