Enhanced lithium storage properties of graphene-based metal oxides by coating with amorphous TiO2 nanofilms

Abstract

Integration of metal oxides with graphene can highly improve their electrochemical performance as promising anode materials for lithium-ion batteries. However, the pulverization, expansion and detachment of metal oxide particles on graphene are still present and lead to the performance degradation after long-term cycling. In this work, TiO2 nanofilms-coated graphene-SnO2 and graphene-Fe2O3 are prepared and exhibit exceptional electrochemical performance, especially great cycling stability, because amorphous TiO2 nanofilms can prevent the pulverization, expansion and detachment of SnO2/Fe2O3 nanoparticles on graphene, and increase the flexibility and mechanical strength of graphene hybrid electrodes. Moreover, it is apt to form thin and stable solid-electrolyte interphase layers on the surface of TiO2 nanofilms rather than the graphene substrate. Accordingly, this novel and facile synthetic procedure offers great promise for the development of high-performance graphene hybrids utilized in various applications such as batteries.