Ultra-small Fe2O3 nanoparticles anchored on ultrasonically exfoliated multilayer graphene for LIB anode application

Abstract

Graphene oxide (GO) and reduced graphene oxide (rGO) have been widely researched as substrates to anchor Fe2O3 nanoparticles. However, both of them suffer from complicated synthesis processes. Multilayer graphene (MLG), simply obtained by ultrasonic exfoliation with graphite, can reduce the cost of actual application due to the facile synthesis. However, it is still a great challenge to anchor Fe2O3 nanoparticles on MLG because of the absence of chemical active sites on its surface. Herein, a chemical deposition method is used to coat highly dispersed ultra-small Fe2O3 nanoparticles on MLG surface. As a comparison, both GO and rGO are also used as substrates to anchor Fe2O3 by the same method. Results show that the oxygen-containing functional groups on substrates have significant effect on the crystal phase and distribution of Fe2O3. A mechanism is thus suggested for the growth of Fe2O3 on MLG, GO and rGO. Among them, the composite of Fe2O3/MLG shows the highest electrochemical performances for lithium ion battery (LIB) anodes. Specific capacity of 1050 mAh g−1 at 0.1C after 100 cycles are obtained based on the total weight of composite. Low cost, facile synthesis and high electrochemical performances enable Fe2O3/MLG to be a prospect anode material for LIBs.