title: Multifunctional Iron Oxide Nanoflake/Graphene Composites Derived from Mechanochemical Synthesis for Enhanced Lithium Storage and Electrocatalysis.
abstract: Composites consisting of nanoparticles of iron oxides and graphene have attracted considerable attention in numerous applications; however, the synthesis methods used to achieve superior functionalities are often complex and unamenable to low-cost large-scale industrial production. Here, we report our findings in exploring a simple strategy for low-cost fabrication of multifunctional composites with enhanced properties. In particular, we have successfully prepared FeO(OH) nanoflake/graphene and nano-Fe3O4/graphene composites from commercially available Fe powders and graphite oxides using a simple and low-cost solid-state process, where the metallic Fe is converted to FeO(OH) nanoflake and graphite oxide is reduced/exfoliated to graphene. The resultant nano-Fe3O4/graphene composite is multifunctional, demonstrates specific capacities of 802 and 629 mA h g(-1), respectively, at 1000 and 2000 mA g(-1) as an electrode material for lithium-ion batteries (LIBs), and also displays efficient catalytic activity for both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER); the nominal overpotentials are lower than those for previously reported metal-based catalysts (e.g., IrO2, RuO2, and Pt/C). The dramatically enhanced properties are attributed to the synergistic mechanochemical coupling effects between iron oxide and graphene introduced by the facile process, which is well suited for large-scale cost-effective fabrication.
authors.forename: Bote
authors.initials: B
authors.lastname: Zhao
authors.affiliation: ∥School of Chemical Engineering, University of Adelaide, Adelaide, South Australia 5005, Australia.
authors.forename: Yao
authors.initials: Y
authors.lastname: Zheng
authors.forename: Fei
authors.initials: F
authors.lastname: Ye
authors.forename: Xiang
authors.initials: X
authors.lastname: Deng
authors.forename: Xiaomin
authors.initials: X
authors.lastname: Xu
authors.affiliation: ⊥School of Materials Science and Engineering, Center for Innovative Fuel Cell and Battery Technologies, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, United States.
authors.forename: Meilin
authors.initials: M
authors.lastname: Liu
authors.affiliation: #Department of Chemical Engineering, Curtin University, Perth, Western Australia 6845, Australia.
authors.forename: Zongping
authors.initials: Z
authors.lastname: Shao
keywords: graphene; iron oxides; lithium-ion batteries; mechanochemical synthesis; nanocomposites; reactive milling