Nonhierarchical Heterostructured Fe2 O3 /Mn2 O3 Porous Hollow Spheres for Enhanced Lithium Storage.

Abstract

High capacity transition-metal oxides play significant roles as battery anodes benefiting from their tunable redox chemistry, low cost, and environmental friendliness. However, the application of these conversion-type electrodes is hampered by inherent large volume variation and poor kinetics. Here, a binary metal oxide prototype, denoted as nonhierarchical heterostructured Fe2 O3 /Mn2 O3 porous hollow spheres, is proposed through a one-pot self-assembly method. Beyond conventional heteromaterial, Fe2 O3 /Mn2 O3 based on the interface of (104)Fe2O3 and (222)Mn2O3 exhibits the nonhierarchical configuration, where nanosized building blocks are integrated into microsized spheres, leading to the enhanced structural stability and boosted reaction kinetics. With this design, the Fe2 O3 /Mn2 O3 anode shows a high reversible capacity of 1075 mA h g-1 at 0.5 A g-1 , an outstanding rate capability of 638 mA h g-1 at 8 A g-1 , and an excellent cyclability with a capacity retention of 89.3% after 600 cycles.